BackgroundAlthough post-traumatic stress disorder (PTSD) is a common co-morbidity in chronic pain, little is known about the association between PTSD and pain in the context of chronic pain rehabilitation.ObjectiveThe aim of the present study was two-fold: (1) to investigate the association of a possible PTSD diagnosis with symptoms of pain, physical and mental functioning, as well as the use of opioids, and (2) to compare the outcome of multidisciplinary chronic pain rehabilitation for patients with a possible PTSD diagnosis at admission with patients without PTSD at admission.MethodA consecutively referred cohort of 194 patients completed a baseline questionnaire at admission covering post-traumatic stress, pain symptoms, physical and mental functioning, as well as self-reported sleep quality and cognitive difficulties. Medication use was calculated from their medical records. A total of 95 were admitted to further multidisciplinary treatment and included in the outcome study.ResultsA high prevalence of possible PTSD was found (26.3%). Patients with possible co-morbid PTSD experienced significantly poorer general and mental health, poorer sleep quality, and more cognitive problems as well as inferior social functioning compared to patients without PTSD. Possible co-morbid PTSD did not result in higher use of opioids or sedatives. Surprisingly, possible co-morbid PTSD at admission was not associated with lower levels of symptom reduction from pre- to post-treatment.ConclusionsPossible co-morbid PTSD in chronic pain is a major problem associated with significantly poorer functioning on several domains. Nevertheless, our results indicate that pain-related symptoms could be treated with success despite possible co-morbid PTSD. However, since PTSD was only measured at admission it is not known whether rehabilitation actually reduced PTSD.

A high prevalence of PTSD was found in both consecutive samples. Using the DSM-IV criteria, 23% fulfilled the criteria for a possible PTSD diagnosis. There were no gender differences in PTSD. The three most reported traumatic events: traffic accidents, serious illness personally or in the family, and the actual loss of someone, were reported as the primary traumatic events by almost 50% of those with PTSD. No particular pain diagnosis was significantly related to PTSD. However, hypersensitivity to cold and hyposensitivity to brush were significantly associated with PTSD. Discussion The prevalence of PTSD in the present study was 23%. Earlier studies finding a lower prevalence rate of PTSD may reflect the use of older diagnostic criteria for PTSD or other estimates, for instance PTSD symptom cut-off scores. Conclusion The study emphasised the importance of screening all chronic pain patients for PTSD at admission for pain rehabilitation, using up to date diagnostic tools. Implications Untreated PTSD may exacerbate or maintain the pain condition and negatively affect outcome of pain rehabilitation.

Background Hypogonadism is prevalent during opioid treatment, but the effect of testosterone replacement treatment (TRT) on body composition, pain perception, and adrenal function is unclear. Purpose To measure changes in body composition, pain perception, quality of life, and adrenal function after TRT or placebo in opioid-treated men with chronic non-malignant pain. Methods Double-blind, placebo-controlled study in 41 men (>18 years) with total testosterone <12 nmol/L were randomized to 24 weeks TRT (Testosterone undecanoate injection three times/6 months, n = 20) or placebo (placebo-injections, n = 21). Outcomes Body composition (lean body mass and fat mass assessed by DXA), clinical pain intensity (numerical rating scale), and experimental pain perception (quantitative sensory assessment), quality of life (SF36), and adrenocorticotrophic hormone (ACTH) test. Data were presented as median (quartiles). Mann–Whitney tests were performed on delta values (24–0 weeks) between TRT and placebo. Results The median age was 55 years (46; 59) and total testosterone before intervention was 6.8 (5.0; 9.3) nmol/L. TRT was associated with change of testosterone levels: 12.3 (7.0; 19.9) nmol/L (P < 0.001 vs placebo), increased lean body mass: 3.6 (2.3; 5.0) kg vs 0.1 kg (−2.1; 1.5) during TRT vs placebo and decreased total fat mass: −1.2 (−3.1; 0.7) kg vs 1.2 kg (−0.9; 2.5) kg, both P < 0.003. Changed pain perception, SF36, and ACTH-stimulated cortisol levels were non-significantly changed during TRT compared with placebo. Conclusions Six months of TRT improved body composition in men with opioid-induced hypogonadism without significant changes in outcomes of pain perception, quality of life, or adrenal function.

According to the new IASP grading system, less than 20% of the patients referred to a multidisciplinary pain center fulfilled the criteria for neuropathic pain. The classification of neuropathic pain with the IASP system varies from the classification of neuropathic pain with the use of a self-administered screening questionnaire.

The association between PTSD and pain intensity is in accordance with the mutual-maintenance and fear-avoidance models. Future studies should investigate changes in pain intensity and mechanisms after treatment targeting comorbid PTSD in chronic pain patients.