Pain
-
We studied the number of musculoskeletal pain sites as a predictor of sickness absence during a 7-year follow-up among a nationally representative sample (the Health 2000 survey) of occupationally active Finns 30 to 55years of age (3420 subjects who did not retire or die during the follow-up). Baseline data (questionnaire, interview, clinical examination by a physician) were gathered in 2000 to 2001 and linked with information from national registers on annual compensated sickness absence periods (⩾10workdays) covering the years 2002 to 2008. Pain during the preceding month in 18 body locations was inquired and combined into 4 sites (neck, upper limbs, low back, lower limbs). ⋯ The confidence intervals of the ORs did not include unity. The adjusted ORs for belonging to the Ascending trajectory were 1.1, 1.3, 1.7, and 1.7, respectively. As the number of pain sites was a strong independent predictor of work absenteeism, early screening of workers with multisite pain and interventions to support work ability seem warranted.
-
Randomized Controlled Trial
Impact of being primed with social deception upon observer responses to others' pain.
This study examined whether priming with social deception affects responses (pain estimates, self-reported sympathy, inclination to help) towards others' pain. We further explored whether the priming effect is mediated by the valence of the patients (positive/negative), as indicated by the participants. First, participants (N=55) took part in an 'independent' delayed memory study in which they read either a neutral text about the use of the health care system (neutral condition) or a text about its misuse (social deception condition). ⋯ Results revealed no direct effect of priming with social deception. However, priming with social deception was related to less positive rating of the valence of the patients, that were related to lower ratings on pain and sympathy, and to larger discrepancies between the ratings of the patients and the observers. The results indicate that observers attribute less pain, feel less sympathy, and take patients' self-reported pain intensity less into account when the patients are evaluated less positively, which is likely to occur when a cognitive scheme of social deception is primed.
-
Persistent pain is a common reason for reduced quality of life after a spinal cord injury (SCI). Biomarkers of neuropathic pain may facilitate translational research and the understanding of underlying mechanisms. Research suggests that pain and affective distress are anatomically and functionally integrated in the anterior cingulate cortex and can modulate sensory and affective aspects of pain. ⋯ The lower Glx/Ins ratio significantly discriminated between SCI-HPI and the A-B (P=.006) and SCI-noNP (P=.026) groups, displayed excellent test-retest reliability, and was significantly related to greater pain severity, interference, and affective distress. This suggests that the combination of lower glutamatergic metabolism and proliferation of glia and glial activation are underlying mechanisms contributing to the maintenance of severe neuropathic pain with significant psychosocial impact in chronic SCI. These findings indicate that the Glx/Ins ratio may be a useful biomarker for severe SCI-related neuropathic pain with significant psychosocial impact.
-
T-type calcium channels encoded by the Ca(V)3.2 isoform are expressed in nociceptive primary afferent neurons where they contribute to hyperalgesia and thus are considered as a potential therapeutic target to treat pathological pain. Here we report that the small organic state-dependent T-type channel antagonist TTA-A2 efficiently inhibits recombinant and native Ca(V)3.2 currents. Although TTA-A2 is a pan Ca(V)3 blocker, it demonstrates a higher potency for Ca(V)3.2 compared to Ca(V)3.1. ⋯ Oral administration of TTA-A2 produced a dose-dependent reduction of hypersensitivity in an IBS model, demonstrating its therapeutic potential for the treatment of pathological pain. Overall, our results suggest that the high potency of TTA-A2 in the depolarized state strengthen its analgesic efficacy and selectivity toward pathological pain syndromes. This characteristic would be beneficial for the development of analgesics targeting T-type channels, in particular for the treatment of pain associated with IBS.