Depression and anxiety are highly prevalent in chronic pain. Clinicians often interpret depression/anxiety as consequences of chronic pain, but some psychiatrists contend that the consequence hypothesis is overrated and that psychiatric symptoms in pain patients should be understood as part of the psychiatric disease. In this overview, the potential bidirectional nature of the relationship between chronic pain and depression/anxiety is discussed on a conceptual level. Two additional possible ways of understanding the relationship are presented: psychological vulnerability can be a risk factor for the chronification of pain, and an underlying mild chronic pain can be exacerbated when the patient encounters a new psychosocial stressor. In clinical practice, it is important not to get stuck in a fruitless chase for a causal understanding. However, it is of great value for clinicians to reflect upon the complexity and dynamic nature of the relationship between pain and depression/anxiety.

Enligt den nyantagna elfte versionen av International Classification of Diseases (ICD-11), som ännu inte översatts till svenska, definieras långvarig smärta som ihållande eller återkommande smärta med mer än 3 månaders varaktighet [1]. Denna tidsgräns är numera väl etablerad inom smärtforskarkollektivet, även om 6 månader ibland också anges [2]. Någon absolut tidsgräns föreligger förstås inte, utan poängen är att termen »långvarig smärta« begripliggör att smärta inte enbart är ett kortvarigt fenomen som beror på en akut vävnadsskada utan att smärta också kan bestå under lång tid – även när en initial skada har läkt ut som den ska. Ett annat sätt att uttrycka det är att smärta inte enbart är ett symtom, utan tämligen ofta i stället kan vara en sjukdom i sig. Enkelt uttryckt: även smärtsinnet kan bli sjukt [3]. Detta sätt att tänka går på tvärs mot allmänhetens intuitiva sätt att tänka om smärta, och det är ett stort problem att tanken på smärta som liktydig med vävnadsskada fortfarande verkar dominera även bland sjukvårdspersonal. Smärta är ett mångfasetterat fenomen, och det är viktigt att sjukvårdspersonal inte har ett stereotypt förhållningssätt utan förmår utföra en smärtanalys som tar hänsyn till smärtans många skepnader [4-11]. Dikotomin akut/långvarig må vara simpel, men för klinisk praxis har den ändå påtagliga praktiska implikationer, till exempel gällande indikationen för att förskriva opioider [4]. Ungefär var femte vuxen är drabbad av påtaglig långvarig smärta [2, 12, 13].

Background: Most people suffering chronic pain are plagued by sleeping difficulties. Cognitive behaviour therapy has produced promising results for insomnia comorbid with chronic pain, but the access to such treatment is often limited. Over the last ten years, interventions aiming to increase cognitive flexibility and physical activity have been assumed to be effective treatments for a variety of conditions, including insomnia and chronic pain. If proven effective, these treatments could constitute the first steps in a stepped care model for chronic pain and insomnia. Methods: Two hundred ninety-nine chronic pain subjects were randomized to Exercise, ACT-based stress management (ACT-bsm), or an active control group. Two hundred thirty-two participants (78%) received their allocated intervention at least to some extent. These participants were evaluated using mixed model analyses for changes in sleep (Insomnia Severity Index, ISI), pain intensity, depression, and anxiety immediately after treatment, six months and twelve months after treatment. Results: The mixed model analyses revealed that Exercise had a positive effect on insomnia compared with the control group and the effect remained after 12 months. No clear effect (i.e., both for completers and for completers together with treatment non-completers) upon ISI was found for the ACT-bsm. Pain intensity decreased significantly both in the exercise group and in the control group. For the two psychological variables (i.e., symptoms of anxiety and depression) were found significant improvements over time but no group differences. The treatment effects for ISI and pain intensity did not reach clinical significance per definitions presented in other relevant studies. Conclusions: Beneficial significant effects on insomnia was confirmed in the exercise condition. However, these changes were probably not clinically important. For pain intensity a general decrease was found in the Exercise condition and in the control condition, while no change occurred in ACT-bsm. No group differences were found for the two psychological variables.

Objective: To explore how demographics, pain, psychosocial factors and insomnia relate to the spread of chronic pain. Methods: The study included 708 patients (68% women; median age 46 years; interquartile range 3557 years) with chronic pain who were referred to a multidisciplinary pain centre. Spreading of pain was assessed using a questionnaire covering 36 anatomically predefined pain regions. Data were collected on demographics, pain symptoms, psychological distress, and insomnia (Insomnia Severity Index). Four sub-categories of chronic pain were established: chronic local pain, chronic regional pain medium, chronic regional pain heavy, and chronic widespread pain. Results: The median number of pain regions was 10 (interquartile range 6-18). Prevalence of chronic pain was as follows: chronic local pain 9%, chronic regional pain medium 21%, chronic regional pain heavy 39%, and chronic widespread pain 31%. In the regression models, being a woman and persistent pain duration had the strongest associations with spreading of pain, but anxiety, pain interference, and insomnia were also important factors. Conclusion: Spreading of chronic pain can only partly be explained by the simultaneous levels of insomnia. Female sex, pain duration, pain interference and anxiety appear to have more significant relationships with the spread of pain. Targeting these factors may lead to improvements in treatment and prevention strategies.

Purpose: This study investigates the prevalence of insomnia and its relationship to other symptoms and health aspects in patients with chronic pain. Methods: Patients with chronic pain conditions (n = 845) referred to a multidisciplinary pain centre completed surveys provided by the Swedish quality registry for pain rehabilitation (SQRP). The SQRP collects data on socio-demographics, health status, symptoms of pain, mood and insomnia and life satisfaction. Results: The majority of patients (65.3%) had clinical insomnia according to the insomnia severity index (ISI). Insomnia correlated significantly but weakly with pain, depression, anxiety and coping; the strongest multivariate correlations were found with depression and anxiety followed by pain interference and pain severity. Pain intensity, depression and anxiety correlated stronger than ISI with respect to the two investigated aspects of health. Conclusions: The prevalence of insomnia is high in patients with chronic pain conditions, but the level of importance in relation to other symptoms for health aspects is low, and the associations with other important symptoms are relatively weak. One way to increase the effects of multimodal rehabilitation programs may be to provide interventions directed specifically at insomnia rather than focusing only on interventions that address pain, depression and anxiety. Implications for Rehabilitation The prevalence of insomnia is high in patients with complex chronic pain conditions. Relatively low correlations existed between insomnia and pain intensity, depression, anxiety and other psychological aspects. Pain intensity, anxiety and depression were more important for perceived health aspects than insomnia. One way to increase the effects of multimodal rehabilitation programs may be to also include interventions directed directly to insomnia.