Capsaicin for neuropathic pain: linking traditional medicine and molecular biology

Capsaicin has long been used as a traditional medicine to treat pain and, recently, its mechanism of analgesic action has been discovered. This review article documents the clinical development of capsaicin to demonstrate that pharmacognosy still has a profound influence on modern-day drug development programs. Capsaicin is a highly selective agonist for the transient receptor potential channel vanilloid-receptor type 1 (TRPV1), which is expressed on central and peripheral terminals of nociceptive primary sensory neurons. Knockout studies have revealed the importance of TRPV1 as a molecular pain integrator and target for novel analgesic agents. Topical application of capsaicin at the peripheral terminal of TRPV1-expressing neurons superficially denervates the epidermis in humans in a highly selective manner and results in hypoalgesia. In three recent randomized controlled trials, a patch containing high-concentration capsaicin demonstrated meaningful efficacy and tolerability relative to a low-concentration capsaicin control patch in patients with peripheral neuropathic pain. Data from clinical practice will determine if the high-concentration capsaicin patch is effective in real-world settings. Copyright (C) 2012 S. Karger AG, Base

A one-year follow-up study of chronic pain in community-dwelling older adults with and without neuropathic pain

Background: Chronic, mostly musculoskeletal pain is common among older adults. Little is known about the prognosis of chronic pain and the neuropathic pain qualities in older adults. We studied a cohort of community-dwelling older adults, clinically assessed their pain states, classified their type of pain (nociceptive, neuropathic or combined) and followed them up for a year. Methods: At baseline, a geriatrician clinically examined all study patients and classified their type of pain in collaboration with a pain specialist. Pain, quality of life and mental health were measured by questionnaires (BPI, GDS-15, BAI and SF-36) and reassessed after 1 year. Results: Despite chronic pain, all patients from the baseline cohort continued to live independently at 1 year. A total of 92 of 106 (87%) patients returned the follow-up questionnaire. Nociceptive pain on its own was present in 48 patients, whereas 44 patients also had neuropathic pain. Most patients (96%) had several pain states at baseline, and 13 patients reported a new pain state at follow-up. On average, there were no significant changes in the pain intensity, pain interference, mood or quality of life in either group between baseline and follow-up. Changes in pain were observed at the individual level, and both intensity and interference of pain at the follow-up had a negative correlation with the baseline value. Conclusions: On average, chronic pain was persistent in our patients, but they were able to live independently despite their pain. At the individual level, both relief and exacerbation of pain were observed, supporting the notion that pain is not inevitable and unremitting among older adults.Peer reviewe

Chronic pain among community-dwelling elderly : a population-based clinical study

Objective: To present the occurrence, characteristics, etiology, interference, and medication of chronic pain among the elderly living independently at home. Design/setting: A total of 460 subjects in three cohorts aged 75, 80 and 85 years respectively received visits by communal home-care department nurses for a cross-sectional survey. Of them, 175 had chronic (duration 3 months) pain with an average intensity of 4/10 and/or moderate interference in daily life. Main outcome measures: Clinical assessment was performed for consenting subjects to define the location, intensity, etiology, type, interference and medications of chronic pain. Results: According to home visits, elderly people with chronic pain rated their health and mobility worse and felt sadder, lonelier and more tired than those without chronic pain. A geriatrician made clinical assessments for 106 patients with chronic pain in 2009-2013. Of them, 66 had three, 35 had two and 5 had one pain condition. The worst pain was musculoskeletal in 88 (83%) of patients. Pain was pure nociceptive in 61 (58%), pure neuropathic in 9 (8%), combined nociceptive and neuropathic pain in 34 (32%), and idiopathic in 2 (2%) patients. On a numerical rating scale from 0 to 10, the mean and maximal intensity of the worst pain was 5.7 and 7.7, respectively, while the mean pain interference was 5.9. Mean pain intensity and maximal pain intensity decreased by age. Duration of pain was longer than 5 years in 51 (48%) patients. Regular pain medication was used by 82 (77%) patients, most commonly paracetamol or NSAIDs. Although pain limited the lives of the elderly with chronic pain, they were as satisfied with their lives as those without chronic pain. Conclusions: Elderly people in our study often suffered from chronic pain, mostly musculoskeletal pain, and the origin of pain was neuropathic in up to 40% of these cases. However, elderly people with chronic pain rarely used the medications specifically for neuropathic pain. Based on increased loneliness, sadness and tiredness, as well as decreased subjective health and mobility, the quality of life was decreased among those with chronic pain compared with those without pain.Peer reviewe

Analgesic purchases among older adults - a population-based study

Background: Pain is a frequent and inevitable factor affecting the quality of life among older people. Several studies have highlighted the ineffectiveness of treating chronic pain among the aged population, and little is known about the prevalence of analgesics administration among community-dwelling older adults. The objective was to examine older adults' prescription analgesic purchases in relation to SF-36 pain in a population-based setting. Methods: One thousand four hundred twenty community-dwelling citizens aged 62-86 years self-reported SF-36 bodily pain (pain intensity and pain-related interference) scores for the previous 4 weeks. The Social Insurance Institution of Finland register data on analgesic purchases for 6 months prior to and 6 months after the questionnaire data collection were considered. Special interest was focused on factors related to opioid purchases. Results: Of all participants, 84% had purchased prescription analgesics during 1 year. NSAIDs were most frequently purchased (77%), while 41% had purchased paracetamol, 32% opioids, 17% gabapentinoids, and 7% tricyclic antidepressants. Age made no marked difference in purchasing prevalence. The number of morbidities was independently associated with analgesic purchases in all subjects and metabolic syndrome also with opioid purchases in subjects who had not reported any pain. Discussion: Substantial NSAID and opioid purchases emerged. The importance of proper pain assessment and individual deliberation in terms of analgesic contraindications and pain quality, as well as non-pharmacological pain management, need to be highlighted in order to optimize older adults' pain management.Peer reviewe

Depressive symptoms are associated with poor outcome for lumbar spine surgery

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Clinically relevant drug-drug interactions and the risk for drug adverse effects among home-dwelling older persons with and without type 2 diabetes

What is known and objective Polypharmacy and age are known to increase the risk for potential drug interactions. Type 2 diabetes has been associated with polypharmacy and several comorbidities. Currently, there is no information on whether the frequency of clinically relevant drug-drug interactions and the risk for drug adverse effects differ between older persons with and without diabetes. The aim of this study was to investigate the frequency of drug-drug interactions and the risk for drug adverse effects in these two groups in primary care. Methods The basic study population consisted of Finnish home-dwelling primary care patients aged >= 65 years (N = 3039). For each person with diabetes, two controls were selected with adjusted age and gender. To collect data, electronic primary care patient records, a structured health questionnaire and a structured health examination conducted by a physician were utilized. Using the SFINX-PHARAO (R) database, drug-drug interactions and the risk for drug adverse effects were evaluated in 182 persons with type 2 diabetes and 176 persons without diabetes. Results and discussion There were no significant differences in the frequency of drug-drug interactions or the risk for drug adverse effects in persons with and without diabetes. At least one clinically relevant interaction was found in 81 (44.5%) persons with diabetes and 73 (41.5%) persons without diabetes. The most common drugs causing interactions included non-steroidal anti-inflammatory drugs (NSAIDs) and warfarin. What is new and conclusion There is no difference in the frequency of drug-drug interactions or risk for drug adverse effects in older home-dwelling persons with and without diabetes. Due to common comorbidities and commonly used drugs among persons with diabetes, drug-drug interactions involving warfarin or NSAIDs in particular should be carefully monitored to avoid drug adverse effects.Peer reviewe

The role of psychosocial risk factors in the burden of headache

Purpose: Psychosocial risk factors are common in headache patients and affect the impact of headache in multiple ways. The aim of our study was to assess how psychosocial risk factors correlate with the headache impact test-6 (HIT-6). To our knowledge this is the first study to evaluate the impact of several psychosocial factors on the HIT-6 score. Patients and methods: Our study population consisted of 469 Finnish female employees reporting headache during the past year. Psychosocial risk factors were assessed using validated, self-administered questionnaires: the generalized anxiety disorder 7-item scale (GAD-7) for anxiety, the major depression inventory (MDI) for depressive symptoms, the ENRICHD short social support instrument (ESSI) for social isolation, the cynical distrust scale for hostility and the Bergen burnout indicator (BBI-15) for work stress. Results: Exploratory factor analysis of the HIT-6 scores revealed two factors, one describing psychological and quality of life aspects affected by headache and the other describing severity of pain and functional decline. Internal consistency of the HIT-6 was 0.87 (95% CI: 0.85-0.89). Correlations between the total HIT-6 score and all measured psychosocial risk factors except for hostility were weak, but statistically significant. Conclusion: The HIT-6 questionnaire has good construct validity and it describes reliably and independently the impact of headache without interference of psychosocial factors in general working-aged female population.Peer reviewe