The journal of pain : official journal of the American Pain Society
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Instruments to assess chronic pain acceptance have been developed and used. However, whether and to what extent the content of the items reflects acceptance remain uninvestigated. A content analysis of 13 instruments that aim to measure acceptance of chronic pain was performed. A coding scheme was used that consisted of 3 categories representing the key components of acceptance, that is, disengagement from pain control, pain willingness, and engagement in activities other than pain control. The coding scheme consisted of 5 additional categories in order to code items that do not represent acceptance, that is, controlling pain, pain costs, pain benefits, unclear, and no fit. Two coders rated to what extent the items of acceptance instruments belonged to one or more of these categories. Results indicated that acceptance categories were not equally represented in the acceptance instruments. Of note, some instruments had many items in the category controlling pain. Further analyses revealed that the meaning of acceptance differs among different instruments and among different versions of the same instrument. This study illustrates the importance of content validity when developing and evaluating self-report instruments. ⋯ This article investigated the content validity of questionnaires designed to measure acceptance in individuals with chronic pain. Knowledge about the content of the instruments will provide further insight into the features of acceptance and how to measure them.
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Identification of patients at increased risk for problem opioid use is recommended by chronic opioid therapy (COT) guidelines, but clinical assessment of risks often does not occur on a timely basis. This research assessed whether structured electronic health record (EHR) data could accurately predict subsequent problem opioid use. This research was conducted among 2,752 chronic noncancer pain patients initiating COT (≥70 days' supply of an opioid in a calendar quarter) during 2008 to 2010. Patients were followed through the end of 2012 or until disenrollment from the health plan, whichever was earlier. Baseline risk indicators were derived from structured EHR data for a 2-year period prior to COT initiation. Problem opioid use after COT initiation was assessed by reviewing clinician-documented problem opioid use in EHR clinical notes identified using natural language processing techniques followed by computer-assisted manual review of natural language processing-positive clinical notes. Multivariate analyses in learning and validation samples assessed prediction of subsequent problem opioid use. The area under the receiver operating characteristic curve (c-statistic) for problem opioid use was .739 (95% confidence interval = .688, .790) in the validation sample. A measure of problem opioid use derived from a simple weighted count of risk indicators was found to be comparably predictive of the natural language processing measure of problem opioid use, with 60% sensitivity and 72% specificity for a weighted count of ≥4 risk indicators. ⋯ An automated surveillance method utilizing baseline risk indicators from structured EHR data was moderately accurate in identifying COT patients who had subsequent problem opioid use.
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Clinical neck pain affects pain sensitivity and coordination of neck muscles, but the impact on the shoulder muscles is unclear. This study investigated the effect of experimental neck pain on the activity of the axioscapular muscles during arm movements and changes in pain sensitivity. Experimental neck pain was induced in 24 healthy volunteers by injecting hypertonic saline into the splenius capitis. Isotonic saline was injected as control. Before, during, and after injections, electromyography was recorded bilaterally from 8 muscles during standardized arm movements (140° scapular plane elevation), and the root mean square amplitude was extracted. Likewise, pressure pain thresholds were assessed bilaterally on 3 sites. The root mean square electromyography was decreased for the ipsilateral upper trapezius (P < .01) and increased for the ipsilateral middle deltoid (P < .03) during upward movements. The root mean square electromyography was reduced for the ipsilateral upper trapezius (P < .01) during downward movement, whereas an increase was recorded in the contralateral external oblique (P < .02). At the injection site, the pressure pain threshold increased during pain compared with the post condition (5 minutes after potential pain had subsided; P < .03). In this study, trunk and axioscapular muscle activities were reorganized in response to localized and referred pain evoked by hypertonic saline injection into an intrinsic neck muscle with no direct attachments to the trunk or shoulder girdle. ⋯ Reorganized activity of the axioscapular muscles has been shown previously in neck pain patients and is believed to happen during the transition from acute to chronic pain. The present study demonstrates for the first time that such reorganization may happen acutely, adding to our understanding of the effects of acute neck pain.
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Current research on the risk of opioid analgesics with drug overdose does not account for the total morphine equivalent dose (MED) of opioids filled by a patient. In this study, time from first opioid prescription until drug overdose was examined for 206,869 privately insured patients aged 18 to 64 with noncancer pain and ≥2 filled prescriptions for Schedule II or III opioids from January 2009 to July 2012. Opioid therapy was examined in 6-month intervals including 6 months before an overdose and categorized as mean daily MED (0, 1-19, 20-49, 50-99, ≥100 mg) and total MED divided at top quartile (0, 1-1,830, >1,830 mg). Survival analysis was used, adjusting for demographics, clinical conditions, and psychoactive drugs. Relative to no opioid therapy, persons at highest risk for overdose (adjusted hazard ratios of 2-3) received a daily MED of ≥100 mg regardless of total dose or a daily MED of 50 to 99 mg with a high total MED (>1,830 mg). The hazard ratio was significantly lower (1.43, 95% confidence interval = 1.15-1.79) for 50 to 99 mg daily MED with a lower total MED (≤1,830 mg), whereas hazard ratios for lower daily MEDs did not differ by total dose. This analysis suggests that clinicians should consider total MED to assess risk of overdose for persons prescribed 50 to 99 mg daily MED. ⋯ When addressing risks for drug overdose, this analysis supports the need for clinicians, administrators, and policy makers to monitor not only daily opioid dose but also total dose for patients receiving 50 to 99 mg daily MED.
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Chronic pruritic conditions are often associated with dry skin and loss of epidermal barrier integrity. In this study, repeated application of acetone and ether followed by water (AEW) to the cheek skin of mice produced persistent scratching behavior with no increase in pain-related forelimb wiping, indicating the generation of itch without pain. Cheek skin immunohistochemistry showed a 64.5% increase in total epidermal innervation in AEW-treated mice compared to water-treated controls. This increase was independent of scratching, because mice prevented from scratching by Elizabethan collars showed similar hyperinnervation. To determine the effects of dry skin treatment on specific subsets of peripheral fibers, we examined Ret-positive, calcitonin gene-related peptide (CGRP)-positive, and glial cell line-derived neurotrophic factor family receptor α3 (GFRα3)-positive intraepidermal fiber density. AEW treatment increased Ret-positive fibers but not CGRP-positive or GFRα3-positive fibers, suggesting that a specific subset of nonpeptidergic fibers could contribute to dry skin itch. To test whether trigeminal ganglion neurons innervating the cheek exhibited altered excitability after AEW treatment, primary cultures of retrogradely labeled neurons were examined using whole-cell patch clamp electrophysiology. AEW treatment produced no differences in measures of excitability compared to water-treated controls. In contrast, a significantly higher proportion of trigeminal ganglion neurons was responsive to the nonhistaminergic pruritogen chloroquine after AEW treatment. We conclude that nonpeptidergic, Ret-positive fibers and chloroquine-sensitive neurons may contribute to dry skin pruritus. ⋯ This study examines the underlying neurobiological mechanisms of persistent dry skin itch. Our results indicate that nonpeptidergic epidermal hyperinnervation and nonhistaminergic pruritic receptors are potential targets for chronic pruritus.