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Opioid Management Debate Sun, 29 Jan 2023 16:00:08 +0000 Joomla! - Open Source Content Management en-gb Sleep Disturbance

What is a sleep disturbance?

Patients with chronic pain frequently experience sleep disturbances. Sleep disturbance is a catchall phrase for any type of problem in sleeping. The most common forms of sleep disturbances in patients with chronic pain are the following:

  • Insomnia
  • Hypersomnia
  • Sleep apnea
  • Restless leg syndrome

Sleep disturbance can make coping with chronic pain more difficult and can actually make pain worse.

Everyone doesn’t cope well when getting poor sleep. After awhile, people tend to find it harder to deal with the normal hassles of life. They get frustrated more easily or they find themselves losing their patience when normally they might have stayed calm. As the duration of the sleep disturbance continues, people tend to get irritated easily or perhaps even tearful more easily.

Chronic pain patients are no different. With on-going sleep disturbances, they also tend to become frustrated or irritated more easily with the normal problems of life. In addition, though, chronic pain patients are dealing with pain. While perhaps not a normal problem in life, chronic pain is a problem. Chronic pain patients have to cope with it. With persistent sleep disturbances, their abilities to deal with it get challenged in just the same way as their abilities to cope with other problems of life. That is to say, it becomes harder and harder to deal with chronic pain when not sleeping well.

On top of it all, sleep disturbances can make chronic pain worse. An on-going lack of refreshing sleep can stress the nervous system. The nervous system consequently becomes more reactive. This reactivity of the nervous system amplifies the pain signals and makes pain worse.

In either case, it is important to resolve the sleep disturbance. It is one way to manage chronic pain well.


Insomnia is a problem of persistent difficulty getting enough sleep. People typically have difficulty either falling asleep when they first lay down or they awake in the early morning and are unable to return to sleep. Sometimes, people experience both difficulties -- falling asleep and staying asleep.

Common causes of insomnia for chronic pain patients are the following:

  • Pain
  • Worry and anxiety
  • Daytime sleeping
  • Night sweats (particularly when taking methadone)

Insomnia can readily develop into a chronic condition because of associations that patients unintentionallymake between going to bed and remaining awake. It’s distressing to be unable to sleep and it makes its mark. People recall it the next night. Apprehension builds over whether it will happen again. The apprehension leads to increased worry and a sense of arousal. This worry and arousal aren’t, of course, conducive to sleeping and so the anticipatory insomnia comes to reinforce insomnia. After a few weeks to months of this vicious cycle, insomnia is hard to break without help.

With regard to a long-term resolution of insomnia, the most effective treatment for insomnia is cognitive behavioral therapy.1, 2, 3 Cognitive behavioral therapy is a short-term psychotherapy, usually provided by a psychologist, that breaks the cycle and creates new associations with going to sleep.

In actual practice, most patients get medications to help them sleep rather than cognitive behavior therapy. Common medications for sleep are the following:

  • hypnotics, like zolpidem and eszopliclone
  • benzodiazepines, like diazepam, clonazepam, or lorazepam
  • tricyclic antidepressants, like trazadone or amitriptyline

While commonly prescribed, these medications are at best mildly effective.

When compared to placebo, people taking hypnotics fall asleep on average 12.8 minutes sooner. People taking benzodiazepine medications fall asleep 10 minutes sooner on average than those taking a placebo. People taking tricyclic antidepressants fall asleep 7 minutes faster than those taking a placebo.4 

The use of these medications involves some risk. Benzodiazepine medications are associated with rebound insomnia (i.e., an exacerbation of insomnia after stopping the use of the medication) and dependency.5 Hypnotic medications are associated with a slight, increased risk for sleep-related activities, like sleep walking or eating.6 

The one advantage of taking a tricyclic antidepressant, particularly amitriptyline, is that, in addition to being a sleep aid, it is one of the most effective pain medications available.7, 8 

Chronic pain rehabilitation programs are also a treatment option. Usually, patients participate in such programs with the goal of learning how to self-manage chronic pain, return to work, and reduce their reliance on the healthcare system. However, an important component of achieving these goals is to resolve or reduce any secondary stressors that occur as a result of living with chronic pain, like on-going insomnia. Most chronic pain rehabilitation programs are cognitive behavioral based and so incorporate cognitive behavioral approaches to insomnia when needed.


Hypersomnia is sleeping too much. When it is in conjunction with chronic pain, most cases of hypersomnia are caused by one of the following:

  • Depression
  • Over-medication

Depression can be fatiguing and so people with chronic pain and depression can sometimes sleep too much. Sleeping too much can also be a form of escape, escaping the distressing realities of living with chronic pain. Over-medication, particularly with opioids, can lead to excessive sedation and consequently sleeping too much.

Chronic pain rehabilitation programs are likely the best treatment option for individuals with chronic pain and hypersomnia. Their focus is to assist patients in acquiring the abilities to self-manage chronic pain. In doing so, patients overcome their depression, when it is secondary to chronic pain, and reduce their need for opioid medications, allowing them to taper these sedating medications.

Sleep apnea

Sleep apnea is a sleep disorder in which people temporarily stop breathing while asleep. The most common form of sleep apnea is obstructive sleep apnea. It is associated with snoring, being overweight, and having cardiovascular disease and type II diabetes. Using sleep studies, sleep specialists diagnose all forms of sleep apnea.

Treatments for sleep apnea are the following:

  • Lifestyle changes, such as losing weight, quitting smoking, and avoiding alcohol
  • Mouth pieces
  • Continuous positive airway pressure devices, or C-PAP’s

It is important to treat sleep apnea as it can significantly improve quality of life. It is also a possibly serious condition, particularly when combined with obesity, type II diabetes, and/or cardiovascular disease. Lastly, patients with chronic pain who are taking long-term opioid medications should especially be concerned about sleep apnea.9 Patients who suspect that they may have sleep apnea should consult their healthcare provider.

Restless leg syndrome

Restless leg syndrome is a condition in which people have restless sensations and an urge to move the legs.It usually occurs at night, while trying to sleep. It is associated with central sensitization.10, 11 Central sensitization is a condition of an over-reactive nervous system and is associated with most chronic pain syndromes.

To treat restless leg syndrome, patients often take medications that are used for Parkinson’s disease.

Chronic pain rehabilitation programs are likely the most effective treatment for chronic pain syndromes that are marked by central sensitization.12 However, there are no clinical studies determining the effectiveness of such programs for restless leg syndrome per se.


1. Mitchell, M. D., Gehrman, P., Perlis, M., & Umscheid, C. A. (2012). Comparative effectiveness of cognitive behavioral therapy for insomnia: A systematic review. BMC Family Practice, 13, 40.

2. Smith, M. T., Perlis, M. L., Park, A., Smith, M. S., Pennington, J., Giles, D. E., & Buyesse, D. J. (2002). Comparative meta-analysis of pharmacotherapy and behavior therapy for persistent insomnia. American Journal of Psychiatry, 159, 5-11.

3. Riemann, D. & Perlis, M. L. (2009). The treatments of chronic insomnia: A review of benzodiazepine receptor agonists and psychological and behavior therapies. Sleep Medicine Reviews, 13, 205-214.

4. Buscemi, N., Vandermeer, B., Friesen, C., Bialy, L., Tubman, M., Ospina, M., Klassen, T. P., & Witmans, M. (2007). The efficacy and safety of drug treatments for chronic insomnia in adults: A meta-analysis of RCTs. Journal of General Internal Medicine, 22, 1335-1350.

5. Longo, L. P. & Johnson, B. (2000). Addiction: Part 1. Benzodiazepines – side effects, abuse risk and alternatives. American Family Physicians, 61, 2121-2128.

6. Morganthaler, T. I. & Silber, M. H. (2002). Amnestic sleep-related eating disorder associated with zolpidem. Sleep Medicine, 3, 323-327.

7. Wong, M., Chung, J. W., & Wong, T. K. (2007). Effects of treatments for symptoms of painful diabetic neuropathy: A systematic review. British Medical Journal, 335, 87.

8. Hauser, W., Wolfe, F., Tolle, T., Uceyler, N. & Sommer, C. (2012). The role of antidepressants in the management of fibromyalgia: A systematic review and meta-analysis. CNS Drugs, 26, 297-307.

9. Walker, J. M., Farney, R. J., Rhondeau, S. M., Boyle, K. M., Valentine, K., Cloward, T. V., & Shilling, K. C. (2007). Chronic opioid use is a risk factor for the development of central sleep apnea and ataxic breathing. Journal of Clinical Sleep Medicine, 3, 455-461.

10. Wallace, D. J. & Clauw, D. J. (Eds.). (2005). Fibromyalgia and other central pain syndromes. Philadelphia: Lippincott Williams and Wilkins.

11. Yunnus, M. B. (2007). Fibromyalgia and overlapping disorders: The unifying concept of central sensitivity syndromes. Seminars in Arthritis and Rheumatism, 36, 339-356.

12. Gatchel, R., J., & Okifuji, A. (2006). Evidence-based scientific data documenting the treatment and cost-effectiveness of comprehensive pain programs for chronic non-malignant pain. Journal of Pain, 7, 779-793.

Date of publication: April 27, 2012

Date of last modification: October 23, 2015

]]> (Murray J. McAllister, PsyD) Complications Fri, 27 Apr 2012 13:14:47 +0000
Depression Depression

What is depression?

From time to time, most people feel down, blue, unhappy, or irritable. These kinds of depressed moods come and go in response to the normal problems of life.

Sometimes, however, depressed moods stay for weeks or months on end. They come to color a person’s view of life in general. Depressed people are down, irritable, unhappy and, on top of it all, they also feel powerless to change their mood and life’s circumstances. So, they also come to feel hopeless.

If these moods continue for an extended period of time, it’s called depression: down and upset, but also feeling powerless to do anything about it, and so therefore hopeless.

Depression is considered a mood disorder. Symptoms of depression are the following:

  • Down and upset mood most every day for more than two weeks
  • Reduced ability to tolerate normal life stressors and so becoming irritable or frustrated easily, impatient, or tearful easily
  • Little interest in engaging in pleasurable activities (e.g., turning down an invitation to a party and staying home instead)
  • Little motivation to engage in daily activities
  • Significant weight loss or gain, often respectively accompanied by decreased or increased appetite
  • Persistent difficulty sleeping or sleeping too much
  • Fatigue or loss of energy
  • Feeling worthless or lowered self-esteem
  • Recurrent self-criticism
  • Poor concentration and short-term memory
  • Persistent thoughts of death or outright thoughts/actions of killing oneself

To be depressed, people don’t have to have every symptom listed above. People tend to have more or less of these symptoms. Moreover, the symptoms they have tend to be more or less intense and impairing.

As such, healthcare providers diagnose depression when patients have at least a certain number and combination of these symptoms.

What causes depression?

The cause of depression is not fully known. It’s common in popular culture to believe that depression is the result of a chemical imbalance in the brain.

Experts in depression, however, acknowledge that this view is not fully correct. There is much more to the picture of what causes depression.

Researchers agree that depression is likely the result of two general factors:

  • Biological or genetic predisposition
  • Persistent stress

It’s well-known that stress changes the nervous system. These changes have physical and psychological consequences. Stress changes the nervous system in ways that lead to altered levels of brain and nervous system chemicals.1, 2, 3 These chemicals are called neurotransmitters and stress hormones. Some of the stress hormones double as neurotransmitters. In turn, these chemicals affect mood, thinking, and behavior, as well as other bodily systems like the gastrointestinal, cardiovascular, and immune systems.

In certain people, such as those who are predisposed to depression, these stress-related changes affect the nervous system in ways that lead to depressive changes in mood, thinking, and behavior.4 In other people, who might be biologically predisposed to other types of conditions, stress-related changes to the nervous system lead to other types of problems in mood, thinking and behavior, or they might lead to problems in the other bodily systems.

As such, most experts agree that for depression to occur both stress-related changes to the nervous system and a predisposition for the nervous system to change in depressive ways are necessary.5 The combination of these factors produces alterations in brain chemicals – neurotransmitters and stress hormones – which leads to depressed mood, thinking and behaviors.

Link between depression and chronic pain

Depression is common among people with chronic pain.6 The majority of depressive episodes occur following onset of chronic pain.7 Numerous investigators have suggested that there must be a common pathway from chronic pain to depression. The likely pathway is the nervous system and its response to stress.

Chronic pain is, of course, a health condition. Health conditions such as back injuries, migraines or arthritis can cause chronic pain. Nonetheless, while it is a health condition, it is also a chronic stressor. It’s physically and emotionally stressful to live in pain all the time. The stress associated with chronic pain affects the nervous system like any other form of stress. In persons already predisposed to depression, the chronic pain leads to chronic stress, which, in turn, changes the nervous system in ways that bring about depression.

Depression makes chronic pain worse

Once depressed, depression can exacerbate chronic pain. It is explainable in terms of both psychological processes and physiological processes.

Psychologically, depression lowers what’s called a person’s frustration tolerance. Frustration tolerance is the ability to handle or deal with problems without getting upset. As people get depressed, their threshold for dealing with problems gets less and less. The things that they used to be able to handle well start to bug them or make them upset. As such, when depressed, people become irritable more easily. They get frustrated or impatient more easily. They become tearful more easily. In general, this aspect of depression is called lowered frustration tolerance.

Depression similarly lowers the ability to deal with chronic pain. As a person with chronic pain gets depressed, pain becomes harder to tolerate, even if, theoretically, the pain level remained the same. Why? It's because the depressed person's tolerance level gets lowered. Once depressed, you just can’t deal with it like you used to. As such, the experience of pain becomes more intense.

In this way, the onset of depression can start a vicious cycle of chronic pain and depression, both of which make each other worse. The more depressed people with chronic pain get, the more pain they experience, which then leads to a greater sense of powerlessness and hopelessness, which subsequently leads to greater depression and more pain.

painPhysiologically, this vicious cycle is explainable through the development of central sensitization. Central sensitization is a condition of the nervous system. The nervous system becomes stuck in a state of heightened reactivity. Central sensitization is what happens when chronic pain chronically stresses out the nervous system as described above. Pain thresholds lower because the nervous system changes and becomes highly reactive. As such, the threshold for stimuli to cause pain lowers.

People with chronic pain tend to exhibit a touch-me-not reaction in the area of their pain. Things that are normally not painful or not very painful – like touch or a mild bump – get registered by the brain as in fact very painful. People without chronic pain often react to people with chronic pain as if they must be hypochondriacs. The truth is, though, that chronic pain involves central sensitization, which makes the brain and the rest of the nervous system set in a ‘hair-trigger’ mode of reactivity.

Numerous investigators have found a link between chronic pain, central sensitization and depression.8, 9, 10, 11 The common pathway from chronic pain to depression is the nervous system becoming stuck in a persistent state of reactivity called central sensitization.

The vicious cycle described above is thus explicable in terms of chronic pain, central sensitization and depression.

Treating depression in chronic pain rehabilitation programs

Chronic pain rehabilitation programs are the only form of chronic pain management that makes it a point to also focus on treating depression. In such programs, patients acquire the abilities to self-manage pain, return to work, and overcome any secondary complications of living with chronic pain, like depression.

Chronic pain rehabilitation programs routinely utilize the most effective treatments for depression, such as cognitive behavioral therapy, antidepressant medications, and mild aerobic exercise.

It is possible to learn to live well despite having chronic pain, and in the process overcome depression.


1. Dranovsky A. & Hen, R. (2006). Hippocampal neurogenesis: Regulation by stress and antidepressants. Biological Psychiatry, 59, 1136-1143.

2. Malberg, J. E. (2004). Implications of adult hippocampal neurogenesis in antidepressant action. Journal of Psychiatry and Neurosciences, 29, 196-205.

3. Tanaka, M., Yoshida, M., Emoto, H., & Ishii, H. (2000). Noradrenaline systems in the hypothalamus, amygdala, and locus coeruleus are involved in the provocation of anxiety: Basic studies. European Journal of Pharmacology, 405, 397-406.

4. Heim, C., Newport, D. J., Mietzko, T., Miler, A. H., & Nemeroff, C. B. (2008). The link between childhood trauma and depression: Insights from HPA axis studies in humans. Psychoneuroendocrinology, 33, 693-710.

5. Banks, S. M., & Kearns, R. D. (1996). Explaining high rates of depression in chronic pain: A diathesis-stress framework. Psychological Bulletin, 119, 95-110.

6. Breivik, H. Collett, B., Ventafridda, V., Cohen, R., & Gallacher, D. (2006). Survey of chronic pain in Europe: Prevalence, impact on daily life, and treatment. European Journal of Pain, 10, 287-333.

7. Knaster, P., Karlsson, H., Estlander, E. M., & Kalso, E. (2012). Psychiatric disorders as assessed with SCID in chronic pain patients: The anxiety disorders precede the onset of pain. General Hospital Psychiatry, 34, 46-52.

8. Klauenberg, S., Maier, C., Assion, H., et al. (2008). Depression and changed pain perception: Hints for a central disinhibition mechanism. Pain, 140, 332-343.

9. Pollard, L. C., Ibrahim, F., Choy, E. H., & Scott, D. L. (2012). Pain thresholds in rheumatoid arthritis: The effect of tender point counts and disease duration. Journal of Rheumatology, 39, 28-31.

10. Tietjen, G. E., Brandes, J. L., Peterlin, B. L., et al. (2009). Allodynia in migraine: Association with comorbid pain conditions. Headache, 49, 1333-1344.

11. Maletic, V. & Raison, C. L. (2009). Neurobiology of depression, fibromyalgia, and neuropathic pain. Frontiers in Bioscience, 14, 5291-5338.

Date of publication: March 25, 2014

Date of last modification: September 8, 2016

]]> (Murray J. McAllister, PsyD) Complications Fri, 27 Apr 2012 13:13:36 +0000
Anxiety Anxiety

What is anxiety?

Anxiety is a normal emotion. Everyone has anxiety on occasion. It is the emotion that people have when something dangerous might happen. Anxiety is closely related to fear. Fear occurs when something dangerous is happening. Anxiety, though, occurs when something dangerous is pending, and hasn’t happened yet, though it could.  

Anxiety can be divided into different aspects: feelings, physical manifestations, thinking, and behaviors.

A number of feelings are associated with anxiety:

  • Apprehension
  • Alarmed
  • Tension
  • Nervousness
  • Doubt in one’s abilities
  • Aimlessness

Corresponding to these feelings, people with anxiety also commonly have the following physical manifestations:

  • Muscle tension
  • Increased perspiration
  • Increased heart rate & blood pressure
  • Gastrointestinal urgency, followed by an upset stomach
  • Increased energy and even shakiness
  • Cold hands & feet

Specific ways of thinking also occur when anxious:

  • Worry
  • Increased focus on the possible danger and all its consequences
  • Thinking about the worst-case scenarios of what might happen (otherwise known as catastrophizing)

When having all these anxious experiences, people tend to behave in specific ways. They are often:

  • Restless
  • Avoidant of activities (particularly those activities that bring about the possible danger)
  • Stay at home
  • Have difficulty completing activities or projects

Sometimes, anxiety becomes persistent. It can then become impairing. It gets in the way of living day to day life. When anxiety is persistent and impairing, it’s considered no longer normal, but rather a disorder.  

Anxiety and the nervous system

Anxiety is a state of the autonomic nervous system. When anxious, people are literally nervous. They are nervous in their feelings, their body, their thinking and in their behavior.  As such, the nervous system is in a heightened state of alarm. The state of alarm is set off by the possibility of a dangerous thing happening.

Psychologists have dubbed this state of alarm the fight-or-flight response. It prepares people for action, for meeting the challenge of the dangerous thing that might happen. To meet these challenges, the nervous system responds with feelings of being alarmed, with physical changes that increase the capacity for action, with an increased cognitive focus on the possible danger, and avoidance behaviors.  

If the danger were actually occurring, this fight-or-flight response of the nervous system would be quite helpful. It would allow for fear-based responses and escape behaviors. In the case of anxiety, the danger isn’t actually happening, but simply might happen. The nervous system prepares by going into fight-or-flight nonetheless. The same responses occur, but the accompanying avoidant behaviors become less goal-directed. In fact, the avoidant behaviors associated with anxiety are in the end quite restless, unproductive and aimless.

The relationship between anxiety and chronic pain

Anxiety is quite possibly the most common condition that accompanies chronic pain. Anxiety tends to go hand in hand with chronic pain. The reason is that pain is a danger signal. The function of pain is to signal danger that something is wrong in the body and requires attention. As such, pain is a warning signal that naturally leads the nervous system to respond with its corresponding alarm – the fight-or-flight response.

The nervous system’s response to pain neatly corresponds to its response to any other danger.

  • Feelings of alarm, apprehension and distress
  • Increased reactivity of the body, such as increased muscle tension, increased heart rate ad blood pressure, gastrointestinal reactivity, and the like
  • Increased cognitive focus on the danger, in this case, pain, and a tendency to worry and catastrophize about it
  • Avoidance behaviors, such as guarding, resting, staying home and not engaging in activities that might bring about or increase pain

In acute pain, these responses might be quite helpful. The corresponding fear allows for seeking help and guarding in order to prevent further injury. In chronic pain, they become anxiety and avoidance behaviors.

In the case of chronic pain, the anxiety and avoidance behaviors become chronic themselves. The chronic anxiety leads to a chronic sense of alarm or distress, which makes patients edgy. Cognitively, it leads to a chronic focus on pain, which pre-occupies the attention of the pain sufferer. Everyday decisions seem to turn on how much pain the patient has at any given time. It also leads to chronic muscle tension, which in turn leads to more pain. Chronic avoidance behaviors subsequently lead to an increasing sense of social isolation, inactivity, de-conditioning and, ultimately, disability.

The common denominator between chronic pain and chronic anxiety is the nervous system. The nervous system has become stuck in a persistent state of reactivity. This state of reactivity is associated with a condition called ‘central sensitization.1, 2, 3, 4 Central sensitization is, at least in part, the process by which acute pain becomes chronic pain.5, 6, 7, 8 As such, anxiety tends to go hand in hand with chronic pain.

Treating anxiety in chronic pain rehabilitation programs

Chronic pain rehabilitation programs are the only form of chronic pain management that makes it a point to also focus on treating anxiety. In such programs, patients acquire the abilities to self-manage pain, return to work, and overcome any complications like anxiety.  

Chronic pain rehabilitation programs routinely utilize the most effective treatments for anxiety, such as cognitive behavioral therapy, antidepressant medications, and mild aerobic exercise.  

It is possible to learn to live well despite having chronic pain, and in the process overcome anxiety.


1. Yunus, M. B. (2007). Fibromyalgia and overlapping disorders: The unifying concept of central sensitivity syndromes.  Seminars in Arthritis & Rheumatism, 36, 339-356.

2. Ji, G., & Neugebauer, V. (2007). Differential effects of CRF1 and CRF2 receptor antagonists on pain-related sensitization of neurons in the central nucleus of the amygdala. Journal of Neurophysiology, 97, 3893-3094.

3. Meeus M., & Nijs, J. (2007). Central sensitization: A biopsychosocial explanation for chronic widespread pain in patients with fibromyalgia and chronic fatigue syndrome. Clinical Journal of Rheumatology, 26, 465-473.

4. Martinez-Lavin, M.  (2007).  Biology and therapy of fibromyalgia: Stress, stress response, and fibromyalgia.  Arthritis Research and Therapy, 9, 216.

5. Rivat, C., Becker, C., Blugeot, A., Zeau, B., Mauborgne, A., Pohl, M., & Benoliel, J. (2010). Chronic stress induces transient spinal neuroinflammation, triggering sensory hypersensitivity and long-lasting anxiety-induced hyperalgesia. Pain, 150, 358-368.

6. Chen, Y. (2009). Advances in the pathophysiology of tension-type headache: from stress to central sensitization. Current Pain and Headache Reports, 13, 484-494.

7. Blackburn-Munro, G., & Blackburn-Munro, R. E. (2001). Chronic pain, chronic stress, and depression: Coincidence or consequence? Journal of Neuroendocrinology, 13, 1009-1023.

8. Imbe, H., Iwai-Liao, Y., & Senba, E. (2006). Stress-induced hyperalgesia: Animal models and putative mechanisms. Frontiers in Bioscience, 11, 2179-2192.

Date of publication: March 20, 2015

Date of last modification: March 14, 2021

]]> (Murray J. McAllister, PsyD) Complications Fri, 27 Apr 2012 13:13:23 +0000

What are complications to pain?

A number of problems are associated with living with chronic pain.

The list could continue, but these problems are often the most common.

Healthcare providers categorize these problems into what are called psychosocial problems. The term refers to issues that are psychological, interpersonal, or social in nature. It is well known that chronic pain can lead to psychosocial problems or make them worse if they occurred prior to the onset of chronic pain.

All these problems are stressful. They are inherently difficult to experience. They are taxing and make those who experience them tense. As stressful problems, they make you physically and emotionally nervous.

Stress on the nervous system makes pain worse. Whatever the initial cause of the chronic pain might have been, pain is ultimately a function of the nervous system. There would be no pain were it not for the nervous system. Stress makes the nervous system more reactive, leading to tension and nervousness. This heightened state of reactivity of the nervous system, or nervousness, makes pre-existing pain worse.

The above-noted psychosocial problems can thus create a vicious cycle of chronic pain. Chronic pain leads to these problems, but once they are occurring they are also stressful. The stress that they create leads to increased pain because of their effect on the nervous system.

Healthcare providers call this constellation of chronic pain, psychosocial problems, and stress a complicated chronic pain syndrome.

It also explains one of the central tenets of chronic pain rehabilitation: that what initially caused the pain is not the only thing that now maintains it on a chronic course. Chronic pain leads to vicious cycles of stressful complications that, in turn, make chronic pain worse. What might start off as having a single, solitary cause comes to have multiple secondary causes.

Date of publication: March 25, 2013

Date of last modification: January 13, 2019

]]> (Murray J. McAllister, PsyD) Understanding Chronic Pain Fri, 27 Apr 2012 13:13:07 +0000
Social Stigma

What is stigma?

Stigma is the social disapproval of a characteristic of a person and, typically, the characteristic is not changeable or not easily changeable. The disapproval is a critical judgment that an individual is not normal and has less worth than those in the norm. A natural response to stigma is shame and shame-based defensive anger.

Personal characteristics that are common objects of stigma are the following:

  • Racial or ethnic identities
  • Religious affiliations or identities
  • Homosexuality
  • Physical disabilities
  • Obesity
  • Mental illness
  • Substance dependence
  • Having HIV or AIDS
  • Being a victim of sexual assault or abuse
  • Chronic pain

Most of these characteristics are not changeable and some of them are not readily changeable. When they are the object of stigma, the person is judged as abnormal and not as good as those in the norm. They are found at fault, despite being unable to change or, at least, easily change.

Stigma adversely affects the lives of those who are the object of it. It can elicit shame and, over time, low self-esteem. It can also elicit defensive anger and resentment. A noteworthy aspect of stigma is that it doesn’t have to actually occur in a particular situation for it to have an adverse effect. People who have been previously stigmatized can come to anticipate it and come to feel it even when it’s not present. As a result, they can develop a certain level of fear or anxiety about it in their personal interactions with others or they can develop a tendency to quickly become defensive or irritable in their interactions with others. Over time, they can come to identify with the stigma, becoming socially isolated or feeling as if they really are different from the norm. The result is a poor self-concept and low self-esteem.

Stigma of chronic pain

Chronic pain patients can be an object of stigma. It’s important to recognize, though, that it’s not the pain itself, which is stigmatized, but what’s perceived as poor coping with pain. After all, when people cope well with pain, they tend to be esteemed. They are seen as strong. It’s not so for people who remain distressed and disabled by pain. They face the social disapproval of stigma.

A common scenario is something like the following. At the onset of pain, most patients receive well wishes and assistance. Their friends and loved ones express understanding and support of their emotional distress and impairments. The friends and loved ones might also offer help with getting to appointments, picking up the kids, and the like. Over time, though, this understanding and support dissipates. Maybe, they become frustrated by what they perceive as a lack of progress in your recovery. Maybe, they disagree with the therapies and procedures you are obtaining. Maybe, they have chronic pain too and they seem to have been able to remain at work and remain active in their life’s other pursuits. In any of these ways, friends and loved ones come to start disapproving of how the chronic pain patient is handling the pain and its management. They see the patient as stuck and want him or her to move on with life. Therein lies the stigmatizing social disapproval.

While there may be a number of sources of stigma as it relates to chronic pain patients, two common ones are a) comparisons to those who cope better with pain, and b) impatience with the patient that he or she is not coping better. Let’s look at these sources more closely.

An often overlooked fact in chronic pain management is the fact that people cope differently with chronic pain. Much of the time, the focus of healthcare providers and their patients is on the level of pain that the patient experiences and trying to reduce it. In this focus, it is easy to assume that there is a direct inverse relationship between pain levels and degrees of coping. Specifically, the assumption is that, as pain levels increase, coping becomes more difficult and vice versa. Is this assumption fully warranted? It is apt to be true that high pain levels will be more difficult to cope with. Think, for example, the pain of torture: even the best copers in the world will ultimately reach a point at which they cannot cope when being tortured. But is it warranted to assume that the reverse is true? Does experiencing difficulty with coping invariably mean that pain levels are high? Might it not be the case that some people's threshold is higher (or lower) than others and so different people come to struggle to cope at different levels of pain? We can recognize that even with high pain levels people have different subjective responses in their attempts to deal with it. Some ways of responding are going to be more effective than others, which is to say, some people will cope better than others, even with high levels of pain.

It is this fact that leads to the problem of stigma. Some people cope better than others with pain – even high levels of pain. Patients with chronic pain are recurrently held to a standard that they should be coping well with their pain. It’s as if to say that because some people cope well with chronic pain all people with chronic pain should cope well. The fact is, though, that some people experience difficulties in coping with chronic pain.

For many, coping well with chronic pain is not easily learned or achieved. Society commonly does not afford patients with chronic pain much patience in the process of learning. For some period of time after onset of pain, as we described, friends and loved ones give patients a break. After awhile, though, they come to expect that patients should have learned how to cope well. Indeed, people come to expect such patients to just know how to do it. Thereby, they come to hold patients to a standard of coping well and they can have little patience for the fact that patients have trouble learning how to do it.

Patients with chronic pain can buy into this standard too. They assume that they should be coping well. When someone judges them for not coping well, it stings because they assume that they should be coping well, but know they aren’t, and the person’s judgment simply brings the discrepancy to light. As such, they feel the shame of stigma. They are stuck: they are failing in what they are supposed to do (i.e. cope well with pain), but don’t know how. On top of it all, someone notices and says something, making it public, as it were. The result is the feeling of shame. Some patients, when feeling such shame, can also become quite defensively angry. A good defense, in this sense, is a good offense.

Consequences of stigma

The stigma of chronic pain can keep patients from getting effective care. To understand how, it’s necessary to return to the point about the difference between pain itself and how people respond to it, or cope with it.

The experience of chronic pain might be divided into two parts: the pain itself and how the patient reacts to it. This reaction involves cognitive, emotional, and behavioral components. It’s what we call coping.

For example, suppose a person with chronic low back pain has a pain flare and the person reacts to the flare in the following manner. He thinks that the pain flare is due to a worsening of the underlying degenerative disc disease in his spine. It reminds him of what he believes about degenerative disc disease – that it is inevitable that it’s going to get worse. He subsequently starts thinking that he better not do anything today for fear of making the degenerative disc disease worse. At times, he finds himself thinking of the future and seeing himself in a wheelchair some day. This manner of thinking about the pain flare corresponds with a certain set of emotional reactions, namely, fear and anxiety. Becoming overwhelmed by the pain and the anxiety about the future, he decides to rest today, remain in bed or on the couch, and keep himself from engaging in the activities that he had previously planned to do. At some point, such as the next day, the pain flare subsides. His thoughts turn to all the things he didn’t get to and how he is behind in everything he had planned to do. He is angry about having to suffer with chronic pain, but at the same time he feels a bit helpless. He thinks of himself as having no control. This next day he spends getting down on himself for everything he was supposed to have done, but didn’t do, because of the pain. As a consequence, he feels pretty hopeless and depressed.

The example shows how coping with pain is a set of reactions to pain that involve cognitive, emotional, and behavioral responses.

Now, here’s the sticking point: Is this person coping poorly or well with chronic pain? The answer might depend upon your frame of reference.

Objectively, from the outside, one might make a reasonable argument that he is not coping well. He was laid up for the day, anxious, and now he’s down on himself for the things he didn’t do yesterday and is slightly depressed about it all.

Undoubtedly, though, at least some chronic pain patients, whose perspective is more from the inside, would argue that he is coping well or, at least, as well as one can under the circumstances. They might assert that at least he got up the next day and tried again to resume his normal activities, as he might have laid in bed all day again out of depression, even if the pain flare had subsided. They might assert that, at least, he didn’t buy a bottle of booze and cope with the pain by getting drunk – or abuse his pain medications and sleep for 24 hours, or worse, yet, kill himself. Compared to any of these reactions, he is coping pretty well.

From this patient perspective, the prior point that he is not coping well might feel stigmatizing. Indeed, the statement that he might be able to cope with the pain better seems to imply that he should have coped with pain better, but didn’t. As such, it implies failure. Moreover, it seems to imply a public acknowledgement of his failure and so therefore shame is the normal reaction.

From the outside perspective, though, the statement that he might be able to cope better with pain is simply a statement of fact – not a moral judgment or accusation. It might even be meant to elicit hope.

Chronic pain rehabilitation providers are often in this position. They evaluate a patient with chronic pain and offer to help the patient cope better with their pain. The provider thinks it would be welcome news for the patient. The intention of the healthcare provider is to say to the patient: you have chronic pain, and even if you can’t ultimately fix the pain, you can always get better at coping with it, get better and better at keeping it from disrupting your life so much; we have a chronic pain rehabilitation program that specializes in helping patients like you cope better – isn’t that a good thing? You should participate in it.

From the outside, the provider sees the treatment option as a good thing, something that would inspire hope, and something that the patient would welcome.

From the inside, though, the patient hears the provider as saying that the patient should learn how to cope better with pain, which implies that the patient isn’t coping well, but should be, and so is failing in this regard. It’s heard as a stigmatizing, open acknowledgement of such failure. The patient subsequently reacts with shame and anger, rejecting the recommendation to participate in the chronic pain rehabilitation program.

The stigma of chronic pain thus keeps patients from obtaining effective treatment.

Chronic pain is known to be difficult to treat. On the one hand, it is chronic. As such, it is not curable. Therapies and procedures designed to reduce pain are, at best, only mildly effective. That is to say, therapies and procedures reduce pain only to some mild extent. They might be worth doing, but they just aren’t real effective. On the other hand, there is no end to how well a patient might get better at coping with pain. Everyday, in chronic pain rehabilitation programs, patients get so good at coping with chronic pain that they return to work, get back engaged in their life, and can do so without the use of opioid pain medications. But stigma can put a halt to such progress. It can make a recommendation to participate in a chronic pain rehabilitation program into what sounds like a moral accusation of failure – that the patient isn’t coping well enough. The patient reacts with shame and anger and subsequently rejecting the recommendation.

Both the provider and the patient leave the appointment frustrated. The provider is frustrated and confused because she thought she was suggesting something good – that the recommendation would inspire hope and optimism for getting better. The patient is frustrated and confused too. How dare the provider be so callous and judgmental? Who’s she to accuse me of not coping well enough? She doesn’t understand what it’s like to have chronic pain.

The stigma of chronic pain creates a divide between providers and patients and adds to the difficulty in achieving effective chronic pain rehabilitation.

Overcoming the stigma of chronic pain

As with any adversity in life, some people with chronic pain cope with pain better than others. It’s not a moral accusation of fault for those who don’t cope so well. It’s simply a statement of fact. It’s just not true that all people deal with natural disasters, cancer, or the loss of a loved one in the same exact manner. Some people deal with such problems better than others. It’s the same with chronic pain.

There might be any number of reasons for it. Maybe it’s because some people have more problems to deal with than others. The sheer accumulation of problems make it hard to deal with any one of them (such as chronic pain) effectively. Maybe some people have had too many problems in the past and so come to the onset of their chronic pain already overwhelmed. Maybe some people’s role models in life didn’t cope well with their own problems and so some patients never learned healthy or effective coping skills to begin with. Maybe some people are simply more naturally adept at coping than others, while others find themselves having to work harder at it – just as there are naturally gifted musicians, athletes, and artists, while others simply have to work harder at attaining proficiency at these skills. The number of explanations might go on and on.

The point here is that the differences in how people cope with chronic pain are not the result of a fault of the person. It’s not because of moral failure. Rather, there are understandable and reasonable explanations as to why some people cope better than others.

Our reactions to these differences is not, and should not be, one of moral accusations of failure for those who don’t cope well. Rather, it typically is, and should be, one of understanding and empathy and a willingness to help teach.

To overcome stigma, providers and patients must challenge themselves to interact with one another without stigma. That is to say, they must challenge themselves to trust one another.

Providers must be patient, understanding, and genuine in their empathy for the difficulties that people can have. In effect, providers need to be trustworthy in their willingness to coach patients on how to cope better. They need to provide reassurance that they do not judge and their behavior has to demonstrate that they are genuine in their non-judgmental stance.

Patients must challenge themselves to be open to feedback. Talk about ways to cope better can be just that – ways to cope better, which are good things. They are not always accusations of ‘why haven’t you already done these things?’ While it’s true that some people, including some providers, are impatient and judgmental of patients who struggle to cope, it’s not true that all people or all providers are judgmental and impatient. Many providers do understand what it is like. They also know how to cope better with pain. They have valuable skills to teach. They are trustworthy. Patients can challenge themselves to trust and learn from the experts. Patients might also challenge their own conceptions that they should have already known how to cope well with pain. Many patients hold themselves to unattainably high standards and feel like a failure even if no one else actually judges them as such. For such patients, they need to challenge themselves to be okay with being in a student role. It is okay to learn from the chronic pain rehabilitation program experts.

Overcoming stigma is not easy, but it is possible. It takes providers and patients working together in a challenging combination of understanding, empathy, and non-judgmental care.

Date of publication: October 26, 2015

Date of last modification: October 26, 2015

]]> (Murray J. McAllister, PsyD) What is Chronic Pain Fri, 27 Apr 2012 13:12:50 +0000
What is Central Sensitization?

Central sensitization is a condition of the nervous system that is associated with the development and maintenance of chronic pain. When central sensitization occurs, the nervous system goes through a process called wind-up and gets regulated in a persistent state of high reactivity. This persistent, or regulated, state of reactivity lowers the threshold for what causes pain and subsequently comes to maintain pain even after the initial injury might have healed.

Nervous SystemCentral sensitization has two main characteristics. Both involve a heightened sensitivity to pain and the sensation of touch. They are called allodynia and hyperalgesia. Allodynia occurs when a person experiences pain with things that are normally not painful. For example, chronic pain patients often experience pain even with things as simple as touch or massage. In such cases, nerves in the area that was touched sends signals through the nervous system to the brain. Because the nervous system is in a persistent state of heightened reactivity, the brain doesn't produce a mild sensation of touch as it should, given that the stimulus that initiated it was a simple touch or massage. Rather, the brain produces a sensation of pain and discomfort. Hyperalgesia occurs when a stimulus that is typically painful is perceived as more painful than it should. An example might be when a simple bump, which ordinarily might be mildly painful, sends the chronic pain patient through the roof with pain. Again, when the nervous system is in a persistent state of high reactivity, it produces pain that is amplified.

Chronic pain patients can sometimes think they must be going crazy because they know intellectually that touch or simple bumps shouldn’t be as uncomfortable or painful as they experience them. Other times, it’s not the patients themselves who think they are crazy, but their friends and loved ones. Friends and loved ones can witness the chronic pain patient grimacing at the slightest touch or crying out at the simplest bump and they think that the chronic pain patient must really be a hypochondriac or something. After all, the contrast between them and the chronic pain patient is stark: the friends and loved ones can be touched or get a bump and it doesn’t send them through the roof. The difference, though, is that the friends and loved ones don’t have a nervous system that is stuck in a persistent state of heightened reactivity, called central sensitization.

In addition to allodynia and hyperalgesia, central sensitization has some other characteristics, though they may occur less commonly. Central sensitization can lead to heightened sensitivities across all senses, not just the sense of touch. Chronic pain patients can sometimes report sensitivities to light, sounds and odors.1 As such, normal levels of light can seem too bright or the perfume aisle in the department store can produce a headache. Central sensitization is also associated with cognitive deficits, such as poor concentration and poor short-term memory.2 Central sensitization also corresponds with increased levels of emotional distress, particularly anxiety.3 After all, the nervous system is responsible for not only sensations, like pain, but also emotions. When the nervous system is stuck in a persistent state of reactivity, patients are going to be literally nervous – in other words, anxious. Lastly, central sensitization is also associated with sick role behaviors, such as resting and malaise,4 and pain behavior.5, 6 

Central sensitization has long been recognized as a possible consequence of stroke and spinal cord injury. However, it has become increasingly clear that it plays a role in many different chronic pain disorders. It can occur with chronic low back pain,7, 8 chronic neck pain,9 whiplash injuries,10 chronic tension headaches,11, 12 migraine headaches,13 rheumatoid arthritis,14 osteoarthritis of the knee,15 endometriosis,16 injuries sustained in a motor vehicle accident,17 and after surgeries.18 Fibromyalgia,19 irritable bowel syndrome,20 and chronic fatigue syndrome,21 all seem to have the common denominator of central sensitization as well.

What causes central sensitization?

Central sensitization involves specific changes to the nervous system. Changes in the dorsal horn of the spinal cord and in the brain occur, particularly at the cellular level, such as at receptor sites.3, 22 

As stated above, it has long been known that strokes and spinal cord injuries can cause central sensitization. It stands to reason. Strokes and spinal cord injuries cause damage to the central nervous system – the brain, in the case of strokes, and spinal cord, in the case of spinal cord injuries. These injuries alter the parts of the nervous system that are directly involved in central sensitization.  

But what about the other, more common, types of chronic pain disorders, listed above, like headaches, chronic back pain, or limb pain? The injuries or conditions that lead to these types of chronic pain are not direct injuries to the brain or spinal cord. Rather, they involve injuries or conditions to the peripheral nervous system – that part of the nervous system that lies outside the spinal cord and brain. How do injuries and conditions associated with the peripheral nervous system lead to changes in the central nervous system, which, in turn, lead to chronic pain in the isolated area of the original injury? In short, how do isolated migraine headaches become chronic daily headaches? How does an acute low back lifting injury become chronic low back pain? How does an injury to a hand or foot become a complex regional pain syndrome?

There are likely multiple factors that lead to the development of central sensitization in these so-called ‘peripheral’ chronic pain disorders. These factors might be divided into two categories:

  • Factors that are associated with the state of the central nervous system prior to onset of the original injury or pain condition
  • Factors that are associated with the central nervous system following onset of the original injury or pain condition

The first group involves those factors that might predispose patients to developing central sensitization once an injury occurs and the second group involves antecedent factors that foster central sensitization once pain starts.

Predisposing factors

There are likely both biological, psychological, and environmental predisposing factors.

Low and high sensitivity to pain, or pain thresholds, are likely in part due to multiple genetic factors.1 While there is no research as of yet to support a causal link between pre-existing pain thresholds and subsequent development of central sensitization following an injury, it is largely assumed that one will be found.

Psychophysiological factors, such as the stress-response, are also apt to play a role in the development of central sensitization. Direct experimental evidence on animals23, 24 and humans,25, 26 as well as prospective studies on humans,27 have shown a relationship between stress and lowering of pain thresholds. Similarly, different types of pre-existing anxiety about pain is consistently related to higher pain sensitivities.28, 29 All these psychophysiological factors suggest that the pre-existing state of the nervous system is an important determinant of developing central sensitization following the onset of pain. It stands to reason. If the stress response has made the nervous system reactive prior to injury, then the nervous system might be more prone to become centrally sensitized once onset of pain occurs.  

There is considerable indirect evidence for this hypothesis as well. A prior history of anxiety, physical and psychological trauma, and depression are significantly predictive of onset of chronic pain later in life.30, 31, 32, 33 The common denominator between chronic pain, anxiety, trauma, and depression is the nervous system. They are all conditions of the nervous system, particularly a persistently altered, or dysregulated, nervous system.

It's not that such pre-existing problems make people more prone to injury or the onset of illness -- as injury or illness is apt to occur on a somewhat random basis across the population. Rather, these pre-existing problems are apt to make people prone to the development of chronic pain once an injury or illness occurs.  The already dysregulated nervous system, at the time of injury, for instance, may interfere with the normal trajectory of healing and thereby prevent pain from subsiding once tissue damage heals.

Factors leading to central sensitization following onset of pain

Antecedent factors can also play a role in the development of central sensitization. The onset of pain is often associated with subsequent development of conditions such as depression, fear-avoidance, anxiety and other stressors. The stress of these responses can, in turn, further exacerbate the reactivity of the nervous system, leading to central sensitization.3, 34 

Poor sleep is also a common consequence of living with chronic pain. It is associated with increased sensitivity to pain as well.35, 36 

In what’s technically called operant learning, interpersonal and environmental reinforcements have long been known to lead to pain behaviors, but it is also clear that such reinforcements can lead to the development of central sensitization.37, 38, 39 

Treatments of central sensitization

Treatments for chronic pain syndromes that involve central sensitization typically target the central nervous system or the inflammation that corresponds with central sensitization. These are antidepressants,40 and anticonvulsant medications,41, 42, 43 and cognitive behavioral therapy.44, 45, 46 While usually not considered to target the central nervous system, regular mild aerobic exercise alters structures in the central nervous system47, 48 and leads to reductions in the pain of many conditions that are mediated by central sensitization. As such, mild aerobic exercise is used to treat chronic pain syndromes marked by central sensitization.49 Non-steroidal anti-inflammatories are used for the inflammation associated with central sensitization.3

Lastly, chronic pain rehabilitation programs are a traditional, interdisciplinary treatment that uses all of the above-noted treatment strategies in a coordinated fashion. They also take advantage of the research on the role of operant learning in central sensitization and have developed behavioral interventions to reduce the associated pain and suffering.50, 51  Such programs are typically considered the most effective treatment option for chronic pain syndromes.52, 53, 54, 55 

More information

For more information, please see these related topics: definition of pain, the neuromatrix of pain, the changing paradigms in chronic pain management, and the mission of the Institute for Chronic Pain to educate the public about empirical-based conceptualizations of pain and its treatments. 


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Date of publication: March 23, 2013

Date of last modification: May 29, 2017

]]> (Murray J. McAllister, PsyD) What is Chronic Pain Fri, 27 Apr 2012 13:12:35 +0000
Chronic Pain Syndrome

What is a chronic pain syndrome?

Your doctor has told you that you have a chronic pain syndrome. What does it mean?

In most cases, chronic pain starts with an acute injury or illness. If the pain of this injury or illness lasts longer than six months, it’s then considered chronic pain. Sometimes, chronic pain subsequently causes complications. These complications, in turn, can make the pain worse. A chronic pain syndrome is the combination of chronic pain and the secondary complications that are making the original pain worse.

Chronic Pain SyndromeChronic pain syndromes develop in what we call a vicious cycle. A vicious cycle is the cycle of pain causing pain: chronic pain that causes secondary complications, which subsequently make the original chronic pain worse.

What are these secondary complications? Chronic pain can lead to some common problems over time. For example, many people tend to have trouble sleeping because of pain. After a while, they are so tired and their patience has worn so thin that everything starts bugging them. They also find that coping with chronic pain gets harder and harder too. Some people stop working. With the job loss, they might come to experience financial problems. The stress of these problems keeps them up at night. Thinking too much in the middle of the night can make the original sleeping problem even worse. It can be hard to shut off the thinking even in the middle day. Chronic pain can also affect the roles people have in the family. They miss out on children’s activities, family functions, and parties with friends. As a result, many people struggle with guilt. Guilt isn’t the only emotion that is common to living with chronic pain. Patients tend to report some combination of fear, irritability, anxiety and depression. Patients also tend to express that they have lost their sense of direction to life. They are stuck. These problems are all common when living with chronic pain.

These problems cause stress. They are called stressors, which means that they are problems that cause stress. These stressors can make pain worse because stress affects the nervous system. It makes the nervous system more reactive and you become nervous. Now, pain is also a nerve related problem. Whatever its initial cause, pain travels along the nervous system to the brain, which is also part of the nervous system. Once reaching the brain, it registers as pain. When stress affects the nervous system, making it more reactive, the pain signals reach the brain in an amplified way. So, stress leads you to have more pain.

The vicious cycles of pain become clear. Chronic pain causes stressful problems, which, in turn, cause stress that makes the pain worse. This combination of chronic pain and the resultant problems that make pain worse is what we call a chronic pain syndrome.


Date of publication: April 27, 2012

Date of last modification: March 24, 2021

]]> (Murray J. McAllister, PsyD) What is Chronic Pain Fri, 27 Apr 2012 13:12:18 +0000
What is Chronic Pain?

Patients and healthcare providers commonly think of pain as a symptom of an underlying injury or illness. Say, for example, you hurt your low back while lifting. Perhaps, you’ve injured a muscle or ligament, or perhaps it’s an injury to the spine, like a disc bulge or herniation. Either way, you now have pain and the pain is the symptom of the injury. The same might be true for any health condition that causes pain, particularly when it first starts.

Acute pain defined

We call this type of pain acute pain.  Acute pain has two characteristics. First, just as described, acute pain is a symptom of an underlying health condition. Second, its duration is relatively short.  Most injuries and illnesses heal within weeks. Some, however, take longer. As a rule of thumb, healthcare providers use a time frame of pain lasting less than six months.

Chronic pain is not long-lasting acute pain

Sometimes pain doesn’t go away. It can last for longer than six months. In fact, it can last for years. In these situations, there is a tendency among patients and some healthcare providers to continue to see the pain as a symptom of the underlying health condition that started it. They think of chronic pain as simply the long-lasting pain of an injury or illness that hasn’t yet healed.

This line of thinking leads to getting a lot of healthcare. Surgeries, injections, and narcotic pain medications are common attempts to reduce pain by focusing on the underlying condition that started the pain. The typical chronic pain patient has had any number of such procedures and therapies.

These procedures and therapies aren’t very effective. At best, they tend to provide temporary reductions in pain. Studies of healthcare expenditures show that in the last twenty years the rates of pain-related surgeries, injections and narcotic pain medications are at an all time high. At the same time, applications for pain-related disability are also at an all time high.1 Obviously, these procedures and therapies don’t work so well.

The truth is, once pain is chronic, it’s pretty hard to stop, particularly if the focus of care is to try to fix the underlying injury or illness that started it all.

The reason is that chronic pain is something more than the pain of a health condition that hasn’t healed. The importance of this point is hard to underestimate.

Chronic pain defined

Chronic pain has two characteristics that are different than acute pain. First, chronic pain lasts longer than six months. Second, and most importantly, chronic pain is pain that occurs in addition to the pain of the original health condition. In fact, the original, underlying condition may or may not have healed. It doesn’t really matter. Chronic pain is pain that has become independent of the underlying injury or illness that started it all.

Once pain has become chronic, attempts to fix the underlying injury or illness that started it tend to fail to reduce pain. The mistake that patients and some healthcare providers make is to think that chronic pain is just a long-lasting version of acute pain. However, chronic pain is pain that has taken on a life of its own. Chronic pain is pain that is occurring over and above the pain of the underlying injury or illness that started it all. As such, attempts to cure the original health condition commonly miss the mark.

Cause of chronic pain

What then is the cause of chronic pain? To answer this question, we need to understand some facts about the nervous system.

Whatever its initial cause, pain is a function of the nervous system. Say you injure your low back. Nerves around the site of the injury detect it and sends signals that travel on a highway of nerves from the injury to the spinal cord and up to the brain. Once they get to the brain, the brain processes the signals and they register as pain in the low back. The whole highway, from the nerves in the low back to the brain, is the nervous system.

At the same time as the signals travel from the injury to the brain, the whole nervous system becomes reactive. Like a fire detector in a building sounding the alarm in response to fire, the nervous system sets off the alarm bells when in pain. Our muscles become tense. We guard and grimace. We cry and are emotionally alarmed. The nervous system controls all these reactions. We can think of it as the whole nervous system going into ‘red alert.’

This reactivity of the nervous system is all well and good when it comes to acute pain. It helps us to know that something is wrong. Becoming alarmed, we protect against further injury and seek help. Once the original injury or illness heals, everything about the nervous system comes back to normal.

In some people, the nervous system can stay in a persistent state of reactivity even upon healing of the original acute injury or illness. The whole nervous system becomes more and more reactive in a process called wind-up. This reactivity of the nervous system comes to maintain pain in a vicious cycle, over and above the pain of the original condition that started it all. The end state of this process is a highly reactive nervous system called central sensitization.

The hallmarks of central sensitization are increasingly widespread pain and increasingly intense pain. Suppose you have an injury to your neck and come to have chronic neck pain. Once central sensitization sets in, you also develop pain in your shoulders and upper back as well as tension headaches. Additionally, the pain becomes so intense that even touch can hurt.

Other problems occur as well with central sensitization. Since the nervous system also controls our emotional lives, a highly reactive nervous system leads to anxiety and irritability, poor sleep, fatigue, and eventually depression. These psychological problems are secondarily stressful. The stress adds to the reactivity of the nervous system, making the pain worse. Another vicious cycle results.

The upshot of it all is that chronic pain is pain causing pain by way of central sensitization.

Central sensitization can occur with all pain conditions. It can occur with spine-related acute injuries, whiplash injuries, fibromyalgia, chronic tension headaches, migraine headaches, rheumatoid arthritis, osteoarthritis, complex regional pain syndromes, and endometriosis. It can occur with injuries from a motor vehicle accident or following surgeries.

The importance of treating the nervous system in chronic pain

Chronic pain is thus categorically different from acute pain. It’s not just that it lasts longer. It’s that the whole nervous system is involved, maintaining the chronicity of the pain, over and above whatever pain that might continue, if any, from the original health condition that started it.

Earlier, we commented on the frequent failure of surgeries, injections, and narcotic pain medications to permanently reduce pain. From here, we can see why. They are attempts to fix the injury or condition that started it all. The original condition, however, is typically not what’s responsible for maintaining the pain in a chronic cycle. That is to say, the treatments fail because none of them address the most important cause of chronic pain – central sensitization.

The only treatment that fully addresses central sensitization is chronic pain rehabilitation.


1. Brook, M. I., Deyo, R. A., Mirza, S. K., Turner, J. A., Comstock, B. A., Hollingworth, W., & Sullivan S. D. (2008). Expenditures and health status among adults with back and neck problems. Journal of the American Medical Association, 299, 656-664.


Date of publication: April 27, 2012

Date of last modification: October 23, 2015

]]> (Murray J. McAllister, PsyD) What is Chronic Pain Fri, 27 Apr 2012 13:11:46 +0000