The journal of pain : official journal of the American Pain Society
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Access to medical care is a major national issue, and several surveys suggest that racial and ethnic differences influence access to care for chronic pain problems. To evaluate the influence of race and ethnicity on access to treatment for chronic pain, a cross-sectional telephone survey was performed in a nationally representative sample of 454 white, 447 African-American, and 434 Hispanic subjects with pain for > or =3 months. Questions explored demographics, pain and its treatment, and perceived access to care. A composite "access" variable combined actual consultation with perceived access. Hispanics were younger, least likely to be insured, and had the least education and lowest income; 61% spoke Spanish at home. Hispanics were significantly less likely to have consulted a primary care practitioner for pain (70%) than whites (84%) or African-Americans (85%). A lower likelihood of consultation also was associated with speaking Spanish, being male, being relatively young (18-34 years old) or single, having limited education, and not being employed. Low "access" to care was associated with being Hispanic and speaking Spanish, being younger or male, having low income or limited education, being employed, and agreeing that financial concerns prevented pain treatment. High "access" was associated with being white or African-American; being older or female or living in a suburban area; having insurance, higher income, or college education; and being unemployed. In multivariate models, low "access" was associated with Hispanic ethnicity and agreement that financial concerns prevented pain treatment. High "access" was associated with more severe pain, having insurance or an income of US 25,000 dollars to US 74,000 dollars, and agreeing that "A doctor or other health care provider is the first person I would go to to discuss my pain." These data suggest that race/ethnicity, other demographic characteristics, and socioeconomic factors influence access to pain care. Hispanic ethnicity predicts limited access. ⋯ The influence of race and ethnicity on access to health care is a major issue in the United States. A national telephone survey suggests that race and ethnicity, along with other demographic and socioeconomic factors, influence access to care for chronic pain.
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Clinical Trial Controlled Clinical Trial
Effects of the N-methyl-D-aspartate receptor antagonist dextromethorphan on temporal summation of pain are similar in fibromyalgia patients and normal control subjects.
Temporal summation of second pain at least partly reflects temporal summation of dorsal horn neuronal responses, and both have been termed windup (WU), a form of nociception-dependent central sensitization. Animal and human experiments have shown that both forms of WU depend on N-methyl-D-aspartate (NMDA) and substance P receptor systems. WU of second pain (WU(SP)) in patients with fibromyalgia (FM) is enhanced compared with normal control (NC) subjects and is followed by exaggerated WU(SP) aftersensations and prolonged WU(SP) maintenance at low stimulus frequencies. Because the enhanced WU(SP) of FM patients could be related to abnormal endogenous modulation of NDMA receptors, we tested the effects of the NMDA receptor antagonist dextromethorphan (DEX) on WU(SP) in FM and NC subjects in a double-blind, placebo-controlled, crossover study. WU(SP) was elicited by trains of 0.7-second duration thermal pulses applied to the glabrous surface of the hands or by 1-second mechanical stimuli to the adductor pollicis muscle of the hands at a frequency of 0.33 Hz. In comparison to baseline and placebo conditions, single oral doses of DEX 60 and 90 mg reduced thermal and mechanical WU(SP) in NC and FM subjects, with DEX 90 mg being most effective. These effects did not differ for male and female NC subjects. FM subjects required less thermal and mechanical stimulus intensity than NC to achieve maximal WU(SP), but the extent of WU(SP) reduction by DEX did not statistically differ between NC and FM subjects for all study conditions. Thus, central pain processing of FM subjects is not different from NC in at least one important aspect, namely their NMDA receptor system responsiveness to pharmacologic inhibition by DEX. ⋯ Results of this study demonstrate that FM patients show abnormal WU(SP) during thermal and mechanical stimulation compared with NC. Because oral doses of the NMDA receptor antagonist DEX attenuated thermal and mechanical WU(SP) similarly in FM patients and NC, other mechanisms than WU(SP) need to be considered for the widespread pain of FM patients. These mechanisms might include tonic nociceptive input from peripheral tissues and/or enhanced descending facilitation.
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The present study sought to investigate to what extent patients with chronic low back pain and pain-free control subjects selectively attend to pain-related stimuli as measured with 2 dot-probe tasks with word stimuli and pictorial stimuli. Selective attentional processing was measured by means of 3 indices: the bias index, a congruency effect, and an incongruency effect. Pain-related fear as a trait measure (Tampa Scale for Kinesiophobia [TSK]) was expected to be positively associated with all indices of selective attentional processing of pain stimuli. Results were analyzed with repeated-measures analysis of variance. An incongruency effect was found for patients and to a significantly less degree for pain-free control subjects on the dot-probe task with pictorial stimuli, indicating that pain patients have difficulty disengaging from threat pictures. Pain-related fear as a trait measure (TSK) was not associated with selective attentional processing of word and pictorial stimuli in either pain patients or control subjects. Results from the present study are discussed, and directions for future research are provided. ⋯ Demonstrating difficulty to disengage from threat might be clinically relevant because patients might pay less attention to fear-disconfirming information and remain engaged in avoidance, which might eventually lead to prolonged anxiety states.
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Case Reports
Botulinum toxin a injection of the obturator internus muscle for chronic perineal pain.
Chronic perineal pain is often a difficult condition to manage. Current treatments include pudendal nerve injections and pudendal nerve release surgery. The obturator internus muscle has a close relationship to the pudendal nerve and might be a potential target for therapeutic intervention. ⋯ A case is presented of refractory perineal pain that was successfully treated by injecting the obturator internus muscle with botulinum toxin A.