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Chronic pain is a massive and costly health problem

 and among the main non-fatal causes of years lived with disability worldwide.

 In the United States alone, an estimated 50 million adults are suffering from chronic pain.

 Huge efforts have been made in past decades to better understand, prevent, and treat chronic pain. A common link between chronic pain and posttraumatic stress disorder (PTSD) has emerged as a result of this research. Many individuals with chronic pain suffer from PTSD due to the incidents that caused trauma-related distress, but chronic pain is also commonly found in individuals with PTSD as their primary disorder. Hence, a better understanding of this comorbidity may be important for the treatment of both disorders.

 vary notably due to differences in sampling and assessment tools. Of importance for the interpretation of prevalence rates, many studies rely on fulfillment of diagnostic criteria based on PTSD screening questionnaires. Two recent systematic reviews reported mean-possible PTSD prevalence rates of 11.7% to 19.1% in clinical pain populations, also noting large subgroup differences.

 Similarly, chronic pain complaints are common in patients with a primary diagnosis of PTSD, with prevalence rates estimated to be as high as 80%.

In a recent systematic review of studies on refugees with PTSD, chronic pain complaints were very common. In some studies, almost all participants reported such complaints.

 Furthermore, several studies have found that higher levels of PTSD symptomatology in patients with chronic pain are associated with higher levels of 

, raising the possibility that the conditions not merely coexist, but may influence one another negatively.

Several theoretical possibilities have been put forward to explain the comorbidity of PTSD and pain. These have mainly focused on shared, predisposing vulnerabilities, or on how the conditions may affect one another.

Asmundson et al suggest that underlying predisposing factors or traits cause the development of both PTSD and chronic pain.

 sensitivity (the tendency to respond with fear due to the assumption that [anxiety] symptoms are harmful), may amplify the intensity of the initial emotional response to a traumatic event, thereby increasing the risk of developing either condition.

 Also, other biological and psychological vulnerabilities have been suggested, such as a lowered physiological threshold for alarm responses and feelings of loss of control and unpredictability.

 Vulnerabilities, together with the circumstances of the traumatic event, affect the emotional responses in the encounter and initiate cascades of cognitive bias, hypervigilance, avoidance behavior, autonomic responses, and muscular responsivity.

 A number of vulnerabilities and processes, then, may make an individual more prone to develop the comorbidity following trauma.

Maybe the most-cited model in the field is the Mutual Maintenance Model.

 This model suggests that chronic pain and PTSD maintain and exacerbate one another through 7 mechanisms. Attentional and reasoning biases toward potentially threatening stimuli as well as catastrophizing are suggested to lead to heightened expectations, overestimations, and selective and negative interpretations of both pain-evoking and fear-evoking stimuli. Furthermore, pain may serve as a traumatic cue, evoking fear and PTSD intrusion and hyperarousal, and vice versa. Avoidant coping styles, depressive symptoms, and fatigue are also potentially intertwined and could lead to physical deconditioning, inactivity, disability—all preventing fear extinction. PTSD-related anxiety may also include pain perception directly. Finally, cognitive overload characterizes both conditions, and it leads to limited capacity to employ adaptive coping strategies.

 developed the Perpetual Avoidance Model, which suggests that PTSD symptomatology begins early post-trauma. Here, dysfunctional cognitions, intrusive symptoms, hyperarousal, avoidance behavior, and inactivity all fuel one another in a circular process. The model posits that pain may be initiated or increased as a function of hyperarousal, leading to reinforced fear-avoidance behavior and inactivity. In addition, Jenewein and colleagues argued that fear-learning deficits and impaired capacity to inhibit fear in PTSD may contribute to increased pain perception, pain sensitivity, and fear responses to painful stimuli.

 This idea builds on classical fear conditioning theory, in which fear-learning deficits cause an over-association of pain cues and prevent adaptive safety learning. Incorrect interpretations of bodily symptoms can lead to reinforcement and catastrophizing.

 As a final note, pain issues can also arise due to anxiety-related tensions.

 on pain sensitization, experimental studies find both increased and decreased pain perception, as well as unaltered pain perception.

 While these mechanisms are not fully understood yet, evidence shows that different pain profiles may be related to different PTSD symptoms and coping mechanisms. In a recent review

, PTSD hyperarousal has been associated with increased pain perception and dissociation with decreased pain perception. Also, the nature of the traumatic event may play a role in how PTSD affects pain sensitization. Combat-related PTSD was found to be associated with increased pain thresholds (the level at which a stimulus is experienced as pain), whereas accident-related PTSD was associated with decreased pain thresholds.

Different coping mechanisms may be related to dissociation and derealization. Whereas dissociation can lead to a reduction of conscious attention toward bodily sensations and incoming stimuli such as pain, anxiety and fearful appraisals may lead to attentional bias toward painful stimuli and thereby a decreased pain threshold. Hence, it seems that accident-related trauma is linked to an anxious and sensitizing reaction, whereas combat-related trauma may lead to a dissociative and habituative reaction. While differences in pain processing can be identified in experimental studies, subjective pain reporting most often points in the direction of a more severe symptom profile in relation to pain, disability, and distress when comorbid PTSD and pain persist.

The biological mechanisms behind pain sensitization and the development of chronic pain are complex but include regulatory mechanisms in the hypothalamic-pituitary-adrenal axis, inflammatory processes, immune system suppression, and fatigue.

Also, more complex interpersonal traumas such as physical and emotional abuse associated with war or sexual assault, for example, are of such a pervasive nature that the ability to trust others can be severely damaged, resulting in attachment insecurities that further increase the risk of developing long-term pain problems.

The high co-occurrence of chronic pain and PTSD and their possible entanglement underline the importance of conducting assessment for both PTSD and pain. Unfortunately, symptom overlap between pain and PTSD makes assessment a challenging task. In particular, symptoms related to the DSM-5 PTSD criterion D and criterion E (

) are also very common in individuals who have chronic pain but do nothave PTSD.

 contains items from the PTSD Checklist for DSM-5 (PCL-5) that are prone to misinterpretation. This exemplifies why screening can be a challenge, as individuals who misinterpret these items will sometimes unintentionally inflate their PTSD symptom scores. The key is to distinguish between the patients who feel upset about the consequences of traumatic pain and those who feel highly upset when thinking about the traumatic event itself. For example, negative beliefs about oneself (line 1) are often tied to a guilty conscience about being unable to fulfill one’s obligations due to pain. Loss of interest in activities and feeling cut off from individuals (lines 2 and 3) are often related to no longer being able to participate in sports and hobbies due to pain. Also, almost everyone with chronic pain at times feels irritable and has difficulty concentrating (lines 4 and 5). Similarly, chronic pain causes sleep problems (line 6). The problem is that intrusion symptoms like “feeling very upset when something reminded you of the stressful experience” (which are understood as unique PTSD symptomatology) are sometimes interpreted by patients as being upset when thinking about how pain hinders participating in activities, and not so much as being upset when thinking about the traumatic event itself.

Keeping the aforementioned challenges in mind, there are several PTSD-screening tools (

) that can easily be used. In accordance with the DSM-5, the PCL-5 covers all 20 PTSD symptoms assessed with the diagnostic interview CAPS-5. Also, there are 2 short-form versions (4 and 8 item) of the PCL-5. Another valid brief screening tool for chronic pain is the PTSD-8. The PTSD-8 includes 8 items covering the 3 PTSD symptom clusters of intrusion, avoidance, and hyperarousal (similar to the criteria of ICD-11) and has shown good overall accuracy when compared to a diagnostic interview in chronic pain.

Similarly, there are good and short instruments for pain complaints. Identification of psychological red flags in patients seeking care for musculoskeletal pain problems or PTSD can be useful in treatment planning, as these are often modifiable. 

 presents selected short screening tools for both pain-related problems and PTSD. The selected screening tools are brief, up-to-date, validated tools useful in the context of comorbid PTSD and pain. Of note, for some patient groups psychological disorders may be associated with stigma and may be more difficult to accept. This is important to recognize as it may have significant impact on what patients report to health care professionals, which is important as diagnostics in this area are highly reliant on self-report.

Case example: mutual maintenance mechanisms

“Jane” is a 38-year-old woman. Ever since a severe car crash, her life has not been the same. She has struggled with chronic pain, and she feels worn out and jumpy. Despite her physiotherapist’s best efforts, Jane continues to struggle to engage in the exercise intervention, and she complains about the exercises making her pain worse.

In psychotherapy, she starts to realize that being “worn out” and “jumpy” are related to the PTSD. Several examples of the integration of the conditions become clear to her:

- She often reports that talking about the trauma increases pain intensity.

- She realizes that her struggle to take on physiotherapeutic treatment was not only due to fear of pain and risk of re-injury, but that pain flare-ups return her to the trauma. In this way, her PTSD has made her highly hesitant to engage and made her feel overwhelmed.

- She begins to realize that both pain and PTSD affect her resources, which are split up between them. On days where PTSD symptoms are severe, she has fewer resources to handle pain, which in turn gets worse.

Interventions in these comorbid cases first and foremost need to be biopsychosocial in nature. Unfortunately, there are very few randomized controlled studies that target comorbid PTSD and pain, making it difficult to devise strong recommendations on best treatments for comorbid PTSD and chronic pain. Although there are good evidence-based treatments for each condition, it is still debated whether both conditions need to be targeted sequentially, in parallel, or by an integrated intervention.

If a sequential approach is chosen, it is important to take into consideration which disorder to treat first. As a rule of thumb, the primary disorder needs to be treated first. However, as previously outlined, the untreated disorder may worsen the other; and it is not always evident which disorder is the primary—particularly not in cases where both conditions developed in parallel.

The parallel approach also poses some challenges. If treated by different providers, collaboration and treatment planning can be difficult. Moreover, the clinicians for each disorder need to make sure that the patient has the resources to engage in both treatments. While an integrated intervention may overcome some of these challenges, there is no exact intervention guidelines for how to integrate the interventions.

Evidence points in the direction of integrating cognitive behavior therapy (CBT) techniques in the treatment of comorbid PTSD28 and chronic pain.

 However, one size may not fit all. The complexity of the trauma needs to be considered. In accident-related trauma (in which the primary symptoms may be musculoskeletal pain with elevated levels of arousal, catastrophizing, and pain-related fear avoidance beliefs), the vicious circle maintaining both pain and PTSD symptoms may be interrupted by interventions such as psychologically informed physiotherapy or an intervention with a cognitive behavioral focus on pain management and exposure to feared activities.

 Also, it has recently been shown that early interventions, including targeting PTSD hyperarousal symptoms and pain-related disability with a physiotherapist-led stress inoculation training intervention combined with physiotherapeutic exercise, was effective in reducing pain-related disability compared to exercises alone.

 For more complex interpersonal traumas, or when chronic pain and PTSD have persisted for years, specific and specialized intervention for both PTSD and chronic pain may be necessary for positive outcomes. With that said, the first step is to be aware of this prevalent co-occurrence of pain and PTSD, which requires a proper assessment of both conditions.

Of course, many other frequently comorbid disorders may further muddle the picture, both for assessment and treatment of both pain and PTSD. For example, many studies on PTSD and pain are conducted in military samples, who are also at increased risk of traumatic brain injuries (TBI) of varying severity. This phenomenon also is true for some type of accidents. There are some studies that show veterans with TBI and PTSD report more pain compared to veterans with either TBI or PTSD alone or neither of them.

Chronic pain and PTSD are also associated with suicidal ideation and violent impulses in veterans despite the presence of TBI.

 While this triad remains largely unexplored, some relevant narrative reviews exist, as well as reflections on treatment (eg, Otis and colleagues

Various psychopharmacological agents can be used to treat comorbid PTSD and chronic pain, but there is limited research. Since such a discussion is beyond the scope of this piece, clinicians are encouraged to investigate for themselves.

We hope this article has shed light on the complexity of the comorbidity of chronic pain and PTSD and sparked an interest in some readers to pursue gaining knowledge on this to the future benefit of patients. We encourage clinicians to always have the comorbidity of pain and PTSD in mind when seeing patients with either chronic pain or PTSD, and to be aware of symptom overlap when screening for possible PTSD in chronic pain. Finally, being aware of the nature of the traumatic event is important for treatment planning. If pain and PTSD is due to the same traumatic event, it may be relevant to consider an integrated or parallel treatment, while complex PTSD due to interpersonal trauma or events dating years back in time may require specific trauma-focused intervention in its own.

is assistant professor in a combined position at Department of Psychology, University of Southern Denmark, and at Specialized Hospital for Polio and Accident Victims. 

is associate professor at Department of Psychology, University of Southern Denmark.

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https://www.apa.org/ptsd-guideline/ptsd.pdf

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33. Balba NM, Elliott JE, Weymann KB, et al. Increased sleep disturbances and pain in veterans with comorbid traumatic brain injury and posttraumatic stress disorder. 

34. Stojanovic MP, Fonda J, Fortier CB, et al. Influence of Mild Traumatic Brain Injury (TBI) and Posttraumatic Stress Disorder (PTSD) on Pain Intensity Levels in OEF/OIF/OND Veterans. 

35. Blakey SM, Wagner HR, Naylor J, et al. Chronic Pain, TBI, and PTSD in Military Veterans: A Link to Suicidal Ideation and Violent Impulses?. 

36. Otis JD, McGlinchey R, Vasterling JJ, Kerns RD. Complicating factors associated with mild traumatic brain injury: Impact on pain and posttraumatic stress disorder treatment. 

The high co-occurrence of chronic pain and PTSD and their possible entanglement underline the importance of conducting assessment for both conditions. 

Exploring the Relationship Between Posttraumatic Stress and Chronic Pain 

If you were to poll physicians and ask which specialty usually takes the lead in the management of chronic pain, no doubt an overwhelming majority would say anesthesiology, with a smaller number saying neurology and physiatry. However, probably few would say psychiatry.

It is odd considering the recent revision of the 

 by the International Association for the Study of Pain, the leading worldwide organization for medical professionals involved in the field of pain: “Pain is always a subjective experience that is influenced to varying degrees by biological, psychological, and social factors.”

 This appears to be almost precisely with what psychiatry deals.

We already know that there is a high degree of comorbidity between 

 with chronic pain and, although it is commonly thought that the mental disorders are always secondary to the pain, research has shown that pain is a common presenting symptom of these disorders.

The papers in this Special Report discuss 2 other problems that frequently occur in those with chronic pain: 

 (PTSD). We have known about the relationship between sleep disorders and chronic pain for years; however, the relationship between pain and PTSD is a more recent finding.

As with depressive and anxiety disorders, it is usually thought that if a sleep disorder is present in a person with chronic pain, the sleep issue is always secondary to the pain. However, this oversimplifies the relationship. The interaction between pain and sleep disorders is often a 2-way street, with each exacerbating the other. Both the pain and the sleep disorder need to be addressed.

Of course, the presence of any type of pain can impair sleep. Patients with peripheral diabetic neuropathic pain often report worse pain in their lower extremities during the night when they are trying to sleep. Those who suffer from complex regional pain syndrome in their lower extremities may complain that it is it painful to have sheets touch their skin due to allodynia, in which stimuli that do not usually cause pain do so. Patients with back pain often report problems with sleep due to pain although, curiously, laying down is the position they usually find most comfortable. In fact, if the pain is worse lying down, it is considered a red flag indicative of serious underlying pathology.

Similarly, disruption in normal sleep cycles can cause pain. More than 45 years ago, research found disruptive sleep in some healthy individuals precipitated the symptoms of fibromyalgia and resulted in widespread pain.

There are few studies on the treatment of comorbid pain and sleep disorders. Although both are commonly treated with medications, there is limited research on using pharmacologic agents when both problems are present. Most of the studies have looked at pregabalin in patients with fibromyalgia.

Opioids and benzodiazepines, medications that are frequently prescribed for patients with chronic pain, may actually exacerbate pain because they can cause hyperalgesia (eg, lower pain threshold). These agents can also exacerbate sleep disorders because of their disruption of normal sleep architecture. Sadly, many lay people and medical professionals mistakenly believe that the sedative side effects of these medications mean they will be beneficial for sleep.

There is much less research on chronic pain and PTSD, although there has been a growing interest in the past few years. 

A limiting factor of the data is that much of the research involves veterans. Due to the nature of our recent wars, many veterans suffer from painful injuries caused by explosions. They frequently suffer from traumatic brain injuries (TBI) of varying severity. In fact, both pain and sleep disorders have both been associated with TBI.

 Of course, few civilians who suffer PTSD have similar experiences, so the role TBI may play in the development of comorbid PTSD and chronic pain remains to be determined. 

In addition, research has shown that PTSD may not only be associated with both pain and sleep disorders, but also play a role in acute pain becoming chronic pain.

Since we have yet to identify a markedly efficacious treatment for PTSD, adding chronic pain as a factor further complicates care decisions. Furthermore, although there has been much speculation as to which factors predispose people to develop PTSD and chronic pain separately, we still have no final answer, and we have limited ability to predict who is at increased likelihood for developing both.

For all 3 problems—PTSD, sleep disorders, and chronic pain—psychologically based therapies appear to be among the most promising treatments. They also do not carry the same risks of exacerbating another condition as do medications.

Since psychiatrists often treat PTSD and even sleep, there is little doubt they will see patients with comorbid chronic pain. Unless psychiatrists also are knowledgeable about pain and its management, we will not be able to provide optimal care for our patients.

 is in private practice in Philadelphia.

This article was originally posted on October 21, 2020, and has since been updated. Scroll down for the 

 of the full print issue in which it appeared. -Ed

The revised International Association for the Study of Pain definition of pain: concepts, challenges, and compromises.

2. Moldofsky H, Scarisbrick P, England R, et al. Musculoskeletal symptoms and non-REM sleep disturbance in patients with “fibrositis syndrome” and health subjects. 

3. Husak AK, Bair MJ. Chronic pain and sleep disturbances: a pragmatic review of their relationships, comorbidities, and treatments. 

4. Lavigne G, Khoury S, Chauny JM, et al. Pain and sleep in post-concussion/mild traumatic brain injury. 

5. Burns JW, Janssen, Lillis T, et al. The transition from acute to persistent pain: the identification of distinct trajectories among women presenting to an emergency department. 

Pain may not often be considered within the realm of psychiatry; however, chronic pain's relationships with sleep disorders and PTSD make it an issue psychiatrists can—and should—address.  

Psychiatry’s Role in the Management of Chronic Pain

Pain has a substantial impact on sleep, and an insufficient amount of restful sleep can increase pain susceptibility. Brief bouts of pain—such as pain due to a traumatic injury or a short-lived medical issue—can cause almost immediate adverse effects on daytime functioning and alertness. The symptoms can begin to manifest as soon as the day after a night of inadequate sleep. Chronic pain can lead to prolonged sleep deprivation that can have physical, emotional, and behavioral complications. For example, in the rheumatologic literature, it has long been noted that there is an association between chronic musculoskeletal pain, sleep disruption, and depression.

 More recent research attempts to elucidate the contributing factors and address treatment planning.

 is a benefit of effective pain management. A pain management strategy may also require dedicated attention to sleep quality and sleep quantity. Evaluation of sleep disturbances in the context of chronic pain requires a comprehensive assessment of subjective symptoms and objective tests, such as sleep questionnaires and an 

. Treatment of sleep issues caused by chronic pain is individualized and multifaceted and must take the chronic pain condition, the specific sleep disturbance, and the psychiatric sequalae into account.

Sleep disturbances caused by chronic pain

It is estimated that between 50% to 80% of those living with chronic pain experience sleep disruption. For example, a study revealed 53% of participants with chronic pain met criteria for insomnia, while only 3% of the pain-free controls met the criteria.

 There is also a potential a dose-response link between the intensity of pain and its impact on sleep.

Insomnia is the most commonly noted sleep disorder associated with chronic pain. A large meta-analysis noted a high prevalence of other sleep disruptions as well, with the 3 most common being insomnia at 72%, restless leg syndrome with a prevalence of 32%, and obstructive sleep apnea with a prevalence of 32%.

 It is notable that the 3 most commonly observed sleep disorders added up to greater than 100%, underscoring the fact that chronic pain can be associated with more than 1 type of sleep disturbance at a time (

There are several mechanisms by which pain interferes with sleep. Pain is an obvious distraction that makes it hard to fall asleep and can lead to waking up at night, especially when pain medication wears off. However, pain also interferes with the physiology of sleep in targeted ways that go beyond the conscious distraction caused by the discomfort. There is a variability in chronic pain diagnoses, and the distinctive types of pain syndromes affect sleep differently. Furthermore, the impact of chronic pain on sleep appears to be multidimensional. Research into various pain syndromes and their physiological impact on sleep provide a range of insights into the ways that pain interferes with sleep.

For example, acute post-surgical pain also has quantifiable effects on sleep, including a measurable decrease in the time spent in the 

 (REM) of sleep. Changes are noted not only after general anesthesia, but also after regional anesthesia.

 This observation suggests that the pain itself (rather than the general anesthetic wearing off) is at least a contributing factor to post-operative pain-associated sleep disturbances.

Fibromyalgia is frequently associated with sleep disturbances.

 Patients with fibromyalgia have reduced short-wave sleep and abnormal α-rhythms, with episodes of wakefulness during non-REM sleep.

 Daytime fatigue and non-restorative sleep are common complaints among patients who have fibromyalgia, and these polysomnogram findings are consistent with inadequate sleep quality, even when patients might seem to have slept for an adequate number of hours.

Neuropathic pain is also associated with sleep disturbances, and there is a strong bidirectional relationship between sleep disturbances and neuropathic features of pain.

Sleep disturbances are common among patients who have chronic, recurrent headaches. Common headache types, including tension headaches and migraines, often have associated symptoms besides pain, including sleep disturbances.

 As with fibromyalgia, the amount of time spent sleeping is not necessarily diminished in patients who have headache-associated sleep disturbances. Instead, it is the restorative effects of sleep that are impacted by chronic headache pain, rather than the total amount of sleep per night. The features of sleep disturbances can also vary with different types of headaches.

Sleep disturbance also can affect a person’s response to pain. As sleep stages are compromised, daytime pain increases through a process of hyperalgesia, in which lower pain stimuli result in higher pain perception and greater pain-associated impairment than would be expected otherwise.

According to research in patients with fibromyalgia, sleep deprivation impairs pain-inhibition pathways that normally help control pain.

 Studies also suggest that sleep deprivation can lead to systemic inflammation that can amplify pain.

 The evidence does not suggest that sleep deprivation can independently cause pain; rather, sleep deprivation may amplify the perception of pain that is already occurring as a result of underlying causes.

It is important to note that, while there is a strong association between sleep disorders and chronic pain and mood disorders, it is very difficult to determine which of these has a stronger impact on the others.

Psychiatric consequences of pain-related sleep disturbances

A number of psychiatric sequelae can complicate pain-induced sleep disturbances. There is a strong relationship between chronic pain that is associated with sleep disturbances and subsequent diagnoses of depression and anxiety.

 Other psychiatric issues, such as delusions, hallucinations, or mania are not commonly noted with pain-induced sleep disturbances.

Studies looking at neuropathic pain suggest that inflammation may be associated with psychiatric changes and behavioral alterations.

 However, experts are not completely sure whether there may be other contributory factors as well, and future research regarding the etiology of psychiatric disturbances in pain-induced sleep disturbances may answer some of the currently unanswered questions about these complex relationships.

Regardless of the exact molecular cause, psychiatric diagnoses of anxiety or depression can cause severe patient distress and may also lead to behavioral changes. These issues must be addressed in the clinical setting so that patients can have access to symptom relief and an improved quality of life.

Because of the bidirectional relationship between pain and sleep disturbances, experts recommend evaluating patients who have chronic pain for undiagnosed sleep disorders.

 Evaluation can include commonly used sleep questionnaires, such as the Mini Sleep Questionnaire (MSQ), the Pittsburgh Sleep Quality Index (PSQI), and the Epworth Sleepiness Scale. Objective measures include polysomnogram, Multiple Sleep Latency Test (MSLT), and Maintenance of Wakefulness Test (MWT). Additionally, screening tests for depression and anxiety are often necessary as well. Key components of the evaluation include diagnosing the sequelae of pain in addition to diagnosing the pain syndrome.

The treatment of pain has far reaching effects beyond pain control. Yet, managing pain-related sleep disturbance is not based on pain management alone. Interventions directly aimed at treating sleep disturbance are associated with a better outcome than interventions aimed at only treating the pain.

Currently, very little research has been done on the optimal treatment of sleep disorders in patients with chronic pain, and there is a lack of formal guidelines for approaching the problem. Research is emerging, however, and some experts recommend tailoring sleep care to the specific patient, rather than using a general approach to managing sleep disturbances for patients in whom chronic pain is believed to be the cause of the sleep problem.

 Some authors even suggest that chronic pain is a triad that includes pain, sleep disturbance, and depression.

There are a number of different treatment approaches for pain-associated sleep disturbances, including cognitive behavioral therapy, medication, and respiratory support during sleep for patients who need it.

 Treatment of chronic pain should always take sleep issues into consideration. Opioids, for instance, can alter sleep architecture, and while there are many disadvantages to long-term use of opioids for treating chronic pain, there are rare situations in which they are prescribed. This treatment can be especially problematic for patients who have respiratory sleep disorders, like sleep apnea. Given the complicated balance involved in chronic pain management, opioids might still be an appropriate part of the treatment plan for certain patients who have respiratory side effects. In these cases, the use of respiratory assistance, such as continuous positive airways pressure (CPAP) during sleep, may be an effective solution.

The overall approach to pain management that is complicated by sleep and psychiatric issues requires a tailored plan. It might or might not involve treatments for more than 1 diagnosis of the pain/sleep disturbance/depression triad. For instance, antidepressants might help with pain control and with mood stabilization. And anticonvulsants may help with pain control while also improving sleep.

 But, despite these obvious potential overlaps in treatment, some patients might benefit from optimal treatment approaches tailored to each diagnosis, even if completely separate treatments for each condition are required to achieve control of symptoms. Pharmacological interventions often must be selected based on the targeted symptoms. Even conservative management approaches, such as counseling, cognitive behavioral therapy, and physical therapy are most effective when they are symptom-specific, because the conservative approaches for treating each condition are not identical.

is Associate Editor Humanities in Neurology, Clinical Assistant Professor Case Western Reserve University School of Medicine, Div. of Medical Education, and Editor in Chief Emeritus of 

This article was originally posted on September 21, 2020, and has since been updated. Scroll down for the 

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11. Nijs J, Mairesse O, Neu D, et al. Sleep disturbances in chronic pain: neurobiology, assessment, and treatment in physical therapist practice. 

Sleep disturbance and chronic pain work together to cause misery for patients, with one exacerbating the other. Here: Tips to address both and bring peace to patients.

Sleep Disturbances as a Sequalae of Chronic Pain 

The association between smoking cigarettes and the risk of developing serious and potentially fatal health problems (most notably cardiovascular diseases, pulmonary diseases, and cancer), has long been accepted fact. However, an additional health problem that may also be associated with smoking has often been overlooked: pain.

Two recent papers indicate a strong association between smoking and pain.

 Among the review’s important findings is that those who suffer from chronic pain are substantially more likely to smoke than are those who do not suffer from chronic pain. Although smoking rates continue to decline in the latter group, this does not appear to be occurring in those with pain.

Cigarette smoking has been cited as a risk factor for a wide variety of painful conditions, including back pain, headache, and diabetic peripheral neuropathy. Smoking appears to be associated with both the development and severity of pain.

 specifically studied the most likely locations of pain among individuals who smoke. The study examined data from a 2003-2004 National Health and Nutrition Examination Survey which contained data from comprehensive bodily pain questionnaires in addition to questions on other health issues, including tobacco use.

 The study compared 1054 participants in the survey who smoked tobacco to 1316 who did not.

Those who smoked were found to be more likely to suffer chronic pain. Although the likelihood of pain was increased throughout the body, the study found that spine pain, and especially low back pain, had the strongest association with smoking. The second strongest association was between headaches and smoking. Smoking was also associated with both trunk pain, which included the chest and abdomen, and limb pain. (All statistical associations drawn from 

This is an interesting and perhaps an unexpected finding. Because of the association between smoking and cardiovascular and cerebrovascular problems, it is easy to see why headaches would be fairly common among individuals who smoke. However, it might be reasonably expected that pain in the trunk and limbs would be more common than pain in the spine. The authors suggest that vascular factors may play a greater role in back pain than is often thought.

Whether e-cigarettes, which are becoming more popular, are any less associated with pain than traditional cigarettes remains an unanswered question.

From personal experience treating patients with chronic pain who also smoke, I know that helping them with smoking cessation attempts can be challenging. Although most patients are often well aware of the risks associated with smoking, their pain and its impact on their lives may make it more difficult for them to quit. Their pain may make them feel restricted, and their ability to participate in previously enjoyable activities is limited. Smoking is one of the few such activities in which they can still indulge. They may also feel that smoking helps them cope with the pain.

There is evidence indicating that nicotine may have some analgesic effects, but abstaining from smoking may cause individuals to suffer hyperalgesia, a 

 Thus, those who smoke may receive temporary relief from tobacco use, and their pain may get worse when they try to stop.

Additionally, depression and anxiety are frequent comorbidities among those with chronic pain, and their presence can also contribute to the challenge of getting patients to 

Ultimately, all evidence points to the importance of convincing patients with chronic pain who also smoke that tobacco is not helpful. Indeed, tobacco may be significantly exacerbating their pain and adding to their misery.

The multitude of challenges can understandably make it difficult to convince patients with chronic pain to stop using tobacco. Unfortunately, there are only a limited number of studies that have sought to investigate the 

Although no single optimal treatment has yet been identified, it appears that while nicotine replacement therapy can be useful, the interventions that are most successful are those that address both the pain and the smoking using 

 In this way, treating tobacco use disorder and comorbid chronic pain is similar to the treatment of pain and iatrogenic opioid use disorder, where there must be management of both problems together in order to be successful in treating either.

Two recent papers look at the subtle and surprising links between smoking and pain in different parts of the body. 

Pain

Exploring the Relationship Between Posttraumatic Stress and Chronic Pain

Psychiatry’s Role in the Management of Chronic Pain

Sleep Disturbances as a Sequalae of Chronic Pain

Pain and Smoking: Is There an Association?

Addressing Pain in Patients With Bipolar Disorder

10 Salient Points About Migraine and Psychiatric Comorbidity

10 Factors Leading to Pain Complaints in the Absence of a Medical Diagnosis

Specialized Brain Training Relieves Phantom Pain

Mind-Body Therapies for the Management of Pain: How Effective Are They?

The Opioid Epidemic Settlements: Who Will Benefit?