The journal of pain : official journal of the American Pain Society
-
Generalized hyperalgesia and impaired pain modulation are reported in chronic low back pain (LBP). Few studies have tested whether these features are present in the acute phase. This study aimed to test for differences in pain presentation in early-acute LBP and evaluate the potential contribution of other factors to variation in sensitivity. ⋯ Four subgroups with distinct features were identified: "high sensitivity," "low CPM efficacy," "high sensitivity/low CPM efficacy," and "low sensitivity/high CPM efficacy." Various factors such as sleep and alcohol were associated with each pain measure. Results provide evidence for generalized hyperalgesia in many, but not all, individuals during acute LBP, with variation accounted for by several factors. Specific pain phenotypes provide candidate features to test in longitudinal studies of LBP outcome.
-
Pain is a common but often ignored symptom in patients with myotonic dystrophy type 2 (DM2). In this explorative study, we assessed qualitative and quantitative aspects of pain in DM2 using 4 questionnaires and quantitative sensory testing. A disease control group (fibromyalgia [FMS]) as well as healthy controls were used to compare the results, because pain in DM2 shows many clinical similarities to pain in FMS. ⋯ Peripheral mechanisms of pain seem to play a role in DM2. The widespreadness of the hyperalgesia suggests central sensitization, but this finding was not supported by the other results. This study opens new avenues for further research and eventually novel treatment strategies, in DM2 as well as in other muscular disorders.
-
Clinical practice guidelines admonish against prescribing opioids for individuals with chronic pain and traumatic brain injury (TBI) because of increased risk for adverse outcomes, yet no studies have described opioid prescribing patterns in these higher-risk patients. Between October 2007 and March 2015, 53,124 Iraq and Afghanistan veterans with chronic pain not prescribed opioids in the previous year were followed for 1 year after completing a Comprehensive TBI Evaluation within the Department of Veterans Affairs health care facilities. ⋯ Veterans with moderate to severe TBI and comorbid post-traumatic stress disorder and depression had an even greater risk of initiating long-term opioid therapy in the year after the Comprehensive TBI Evaluation (adjusted relative risk = 3.57 [95% confidence interval = 2.85-4.47]). Higher-risk patients with chronic pain and TBI with mental health comorbidities may benefit from improved access to behavioral health and nonpharmacological therapies for chronic pain.
-
Migraineurs with aura (MWA) express higher interictal response to non-noxious and noxious experimental sensory stimuli compared with migraineurs without aura (MWoA), but whether these differences also prevail in response to everyday non-noxious stimuli is not yet explored. This is a cross-sectional study testing 53 female migraineurs (30 MWA; 23 MWoA) who underwent a wide battery of noxious psychophysical testing at a pain-free phase, and completed a Sensory Responsiveness Questionnaire and pain-related psychological questionnaires. The MWA group showed higher questionnaire-based sensory over-responsiveness (P = .030), higher magnitude of pain temporal summation (P = .031) as well as higher monthly attack frequency (P = .027) compared with the MWoA group. ⋯ Sensory responsiveness scores were positively correlated with attack frequency (r = .361, P = .008) and temporal summation magnitude (r = .390, P = .004), both regardless of migraine type. MWA express higher everyday sensory responsiveness than MWoA, in line with higher response to experimental noxious stimuli. Abnormal scores of sensory responsiveness characterize people with sensory modulation dysfunction, suggesting possible underlying mechanisms overlap, and possibly high incidence of both clinical entities.
-
Healthy humans can be divided into the pain adaptive (PA) and the pain nonadaptive (PNA) groups; PA showed a greater decrease in pain rating to a cold pressor test (CPT) than PNA. This study examined if the dichotomy of pain adaptability existed in individuals with chronic musculoskeletal pain. CPTs at 2°C and 7°C were used to assess the status of pain adaptability in participants with either chronic nonspecific low back pain or knee osteoarthritis. ⋯ The dichotomy of pain adaptability exists in musculoskeletal pain patients. Consistent with the healthy human study, the strength of pain adaptability and potency of CPM are not related. Pain adaptability could be another form of endogenous pain inhibition of which clinical implication is yet to be understood.