The journal of pain : official journal of the American Pain Society
-
This study examined the associations between acculturation and orofacial pain and healthcare among Hispanic adults. Understanding the effects of acculturation on Hispanic oral health may improve understanding of oral health disparities in the United States. Data were collected from 911 Hispanic adults reporting tooth pain and painful oral sores who were part of a larger study of South Florida residents conducted using random-digit dialing methodology. The survey was conducted in Spanish or English by bilingual interviewers per the choice of each respondent. Greater use of the Spanish language was associated with disparities in healthcare visits for orofacial pain, not having a usual dentist, having greater pain, increased difficulty eating and sleeping, and more depression. Respondents' and their parents' nativity (families that had been in the United States longer) and those identifying more closely to Hispanic culture were also predictive of several of the outcomes. Gender, financial status, and age, independent of acculturation, were also associated with orofacial pain, accessing health care, and pain-related loss of functioning among Hispanics. The data support the hypothesis that Hispanics with less acculturation are less able to access needed oral health care. This study highlights the need for outreach programs targeting recent Hispanic immigrants focusing on oral health care. ⋯ This study found that lower levels of acculturation, particularly less frequent use of English, were associated with greater oral pain and depression for Hispanics adults. This emphasizes the need to provide Hispanic patients with information in Spanish and the importance of having bilingual materials and staff in dental clinics.
-
To investigate the mechanisms underlying cancer pain, we developed a rat model of cancer pain by inoculating SCC-158 into the rat hind paw, resulting in squamous cell carcinoma, and determined the time course of thermal, mechanical sensitivity, and spontaneous nocifensive behavior in this model. In addition, pharmacological and immunohistochemical studies were performed to examine the role played by transient receptor potential vanilloid (TRPV)1 and TRPV2 expressed in the dorsal root ganglia. Inoculation of SCC-158 induced marked mechanical allodynia, thermal hyperalgesia, and signs of spontaneous nocifensive behavior, which were diminished by systemic morphine administration. Intraplantar administration of the TRPV1 antagonist capsazepine or TRP channels antagonist ruthenium red did not inhibit spontaneous nocifensive behavior at all. However, intraplantar administration of capsazepine or ruthenium red completely inhibited mechanical allodynia and thermal hyperalgesia produced by SCC-158 inoculation. Immunohistochemically, the number of TRPV1-positive, large-sized neurons increased, whereas there was no change in small-sized neurons in the dorsal root ganglia. Our results suggest that TRPV1 play an important role in the mechanical allodynia and thermal hyperalgesia caused by SCC-158 inoculation. ⋯ We describe a cancer pain model that induced marked mechanical allodynia, thermal hyperalgesia, signs of spontaneous nocifensive behavior, and upregulation of TRPV1. Mechanical allodynia and thermal hyperalgesia were inhibited by TRP channel antagonists. The results suggest that TRPV1 plays an important role in the model of cancer pain.
-
Meta Analysis
Acupuncture for tension-type headache: a meta-analysis of randomized, controlled trials.
We investigated the efficacy and safety of acupuncture for the treatment of tension-type headache by conducting a systematic review and meta-analysis of randomized, controlled trials. The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CINAHL, and PsycINFO were searched from inception through August 2007. No search or language restrictions were applied. Eight randomized, controlled trials met our inclusion criteria. Pooled data from 5 studies were used for the meta-analysis. Our primary outcome was headache days per month. We assessed data from 2 time points: During treatment and at long-term follow-up (20-25 weeks). The weighted mean difference (WMD) between acupuncture and sham groups was used to determine effect size, and a validated scale was used to assess the methodological quality of included studies. During treatment, the acupuncture group averaged 8.95 headache days per month compared with 10.5 in the sham group (WMD, -2.93 [95% CI, -7.49 to 1.64]; 5 trials). At long-term follow-up, the acupuncture group reported an average of 8.21 headache days per month compared with 9.54 in the sham group (WMD, -1.83[95% CI, -3.01 to -0.64]; 4 trials). The most common adverse events reported were bruising, headache exacerbation, and dizziness. ⋯ This meta-analysis suggests that acupuncture compared with sham for tension-type headache has limited efficacy for the reduction of headache frequency. There exists a lack of standardization of acupuncture point selection and treatment course among randomized, controlled trials. More research is needed to investigate the treatment of specific tension-type headache subtypes.
-
Randomized Controlled Trial
Massage reduces pain perception and hyperalgesia in experimental muscle pain: a randomized, controlled trial.
Massage is a common conservative intervention used to treat myalgia. Although subjective reports have supported the premise that massage decreases pain, few studies have systematically investigated the dose response characteristics of massage relative to a control group. The purpose of this study was to perform a double-blinded, randomized controlled trial of the effects of massage on mechanical hyperalgesia (pressure pain thresholds, PPT) and perceived pain using delayed onset muscle soreness (DOMS) as an endogenous model of myalgia. Participants were randomly assigned to a no-treatment control, superficial touch, or deep-tissue massage group. Eccentric wrist extension exercises were performed at visit 1 to induce DOMS 48 hours later at visit 2. Pain, assessed using visual analog scales (VAS), and PPTs were measured at baseline, after exercise, before treatment, and after treatment. Deep massage decreased pain (48.4% DOMS reversal) during muscle stretch. Mechanical hyperalgesia was reduced (27.5% reversal) after both the deep massage and superficial touch groups relative to control (increased hyperalgesia by 38.4%). Resting pain did not vary between treatment groups. ⋯ This randomized, controlled trial suggests that massage is capable of reducing myalgia symptoms by approximately 25% to 50%, varying with assessment technique. Thus, potential analgesia may depend on the pain assessment used. This information may assist clinicians in determining conservative treatment options for patients with myalgia.
-
The objective of this study was to assess the impact of persistent inflammation on spinal gamma-aminobutyric acid-A (GABA-A) receptor-mediated modulation of evoked nociceptive behavior in the adult rat. Nocifensive threshold was assessed with von Frey filaments applied to the dorsal surface of the hind paw. The GABA-A receptor agonist muscimol, the antagonist gabazine, the benzodiazepine receptor agonist midazolam, and antagonists PK11195 and flumazenil were administered spinally in the presence and absence of complete Freund's adjuvant (CFA)-induced inflammation. In naive rats, muscimol increased and gabazine decreased nociceptive threshold. After CFA, the effects of these compounds were reversed: Low doses of muscimol exacerbated the inflammation-induced decrease in nociceptive threshold and gabazine increased nociceptive threshold. Midazolam increased nociceptive threshold both in the presence and absence of inflammation. Flumazenil but not PK11195 blocked the analgesic effects of midazolam. These findings indicate that inflammation-induced changes in GABA-A signaling are complex and are likely to involve several distinct mechanisms. Rectifying the changes in GABA-A signaling may provide effective relief from hypersensitivity observed in the presence of inflammation. ⋯ An inflammation-induced shift in spinal GABA-A receptor signaling from inhibition to excitation appears to underlie inflammatory pain and hypersensitivity. Use of GABA-A receptor selective general anesthetics in association with therapeutic interventions may be contraindicated. More importantly, rectifying the changes in GABA-A signaling may provide effective relief from inflammatory hypersensitivity.