Comparison between acupuncture therapy and gabapentin for chronic pain: a pilot study.

BACKGROUND: We examined whether the effect of true electroacupuncture on pain and functionality in chronic pain participants can be differentiated from that of medication (gabapentin) by analyzing quantitative sensory testing (QST). METHODS: We recruited chronic back and neck pain participants who received six sessions (twice weekly) of true electroacupuncture versus sham electroacupuncture or 3 weeks of gabapentin versus placebo treatment. QST profiles, pain scores, and functionality profile were obtained at baseline (visit 1) and after three sessions (visit 4) or six sessions (visit 7) of acupuncture or 3 weeks of gabapentin or placebo. RESULTS: A total of 50 participants were analyzed. We found no differences in QST profile changes (p = 0.892), pain reduction (p = 0.222), or functionality (p = 0.254) between the four groups. A major limitation of this pilot study was the limited number of study participants in each group. CONCLUSION: This pilot study suggests that a large-scale clinical study with an adequate sample size would be warranted to compare acupuncture and medication therapy for chronic pain management. TRIAL REGISTRATION NUMBER: NCT01678586 (ClinicalTrials.gov).

Chronic Opioid Therapy Modifies QST Changes After Ketamine Infusion in Chronic Pain Patients.

The long-term effects of opioids on sensitization processes are believed to be mediated through the N-methyl-D-aspartate receptor. Quantitative sensory testing (QST) changes observed after a ketamine infusion have been previously described but the effect that chronic opioids will have is not known. The results of this prospective randomized factorial trial compared the thermal QST changes observed after a .05 mg/kg ketamine infusion or a saline placebo in chronic pain subjects who were either opioid-naive or were chronically using opioids for chronic noncancer pain are presented. No baseline QST differences were noted between the 4 groups at baseline. Comparison of changes preinfusion with postinfusion QST measurements resulted in decreased average change in temporal summation response between opioid subjects who received a placebo compared with those who received a ketamine infusion (-5.22, SD = 9.96 vs 13.81, SD = 19.55; P = .004). Additionally, the average change in temporal summation was decreased among subjects who received a ketamine infusion and were not chronically using opioids compared with subjects who were using chronic opioids and received a placebo infusion (-1.91, SD = 13.25 vs 13.81, SD = 19.55; P = .007). The results indicate that low-dose ketamine infusions produce subtle changes in QST phenotypes that are modified by the chronic use of opioids. This illustrates the potential diagnostic and therapeutic value of ketamine in the setting of chronic opioid use. PERSPECTIVE: The presented data further our understanding of modulation of sensory perception in the setting of chronic opioid use and the role of the N-methyl-D-aspartate receptor. The use of low-dose ketamine infusions may be useful for the treatment as well as diagnosis of opioid-related neuropathic conditions.

Lack of correlation between opioid dose adjustment and pain score change in a group of chronic pain patients.

UNLABELLED: Despite the increasing use of opioid analgesics for chronic pain management, it is unclear whether opioid dose escalation leads to better pain relief during chronic opioid therapy. In this study, we retrospectively analyzed clinical data collected from the Massachusetts General Hospital Center for Pain Medicine over a 7-year period. We examined 1) the impact of opioid dose adjustment (increase or decrease) on clinical pain score; 2) gender and age differences in response to opioid therapy; and 3) the influence of clinical pain conditions on the opioid analgesic efficacy. A total of 109 subjects met the criteria for data collection. We found that neither opioid dose increase, nor decrease, correlated with point changes in clinical pain score in a subset of chronic pain patients over a prolonged course of opioid therapy (an average of 704 days). This lack of correlation was consistent regardless of the type of chronic pain including neuropathic, nociceptive, or mixed pain conditions. Neither gender nor age differences showed a significant influence on the clinical response to opioid therapy in these subjects. These results suggest that dose adjustment during opioid therapy may not necessarily alter long-term clinical pain score in a group of chronic pain patients and that individualized opioid therapy based on the clinical effectiveness should be considered to optimize the treatment outcome. PERSPECTIVE: The study reports a relationship, or lack thereof, between opioid dose change and clinical pain score in a group of chronic pain patients. The study also calls for further investigation into the effectiveness of opioid therapy in the management of chronic nonmalignant pain conditions.

Opioid therapy for chronic pain: physicians' attitude and current practice patterns.

Although opioid therapy is widely used for the treatment of chronic pain conditions, there is a lack of consensus on a number of practical issues related to the use of prescription opioids. The authors conducted a comprehensive practice-oriented survey to examine physicians' attitudes, knowledge, experience, and practice patterns regarding opioid therapy for chronic pain management. The survey was conducted during 2007 and 2008 through nationwide direct mails and e-mails to physicians who are currently practicing in the United States. The survey contained 23 questions divided into six categories: (1) physicians' overall view on opioid therapy for chronic pain management; (2) clinical indications for opioid therapy; (3) patient-related factors influencing the decision to begin opioid therapy; (4) effectiveness of opioid therapy; (5) choice of opioid regimen; and (6) opioid agreement and opioid abuse behavior. The survey results suggest that opioid therapy remains as an important treatment option for chronic malignant and nonmalignant pain. However, the survey results should be viewed in the context of a low response rate (18.2 percent). These results also suggest that by improving the clinical knowledge of physicians participating in opioid therapy through education and collaboration, including a team approach with consultation from pain specialists, psychologists, and others, a better outcome for opioid therapy in patients with chronic pain conditions could be achieved.

A survey of selected physician views on acupuncture in pain management.

OBJECTIVES: To collect information on the role of acupuncture in pain management from pain physicians and referral physicians who manage clinical pain conditions. METHODS: The survey was conducted between 2007 and 2008 through nationwide direct mail or e-mail to 1083 physicians who are currently practicing in the United States. We divided our 16 survey questions into five categories: 1) physician's attitude toward acupuncture as a modality of pain management; 2) physician's preference or belief with regard to the type of pain condition suitable for acupuncture referrals; 3) timing for making acupuncture referrals (e.g., acupuncture as a first line pain treatment option or a last approach after failed conventional pain management); 4) clinical assessment criteria for the effectiveness of acupuncture therapy; and 5) barriers to making acupuncture referrals (e.g., physician's personal view, insurance issues, patient refusal, etc.). The survey results were calculated and interpreted as the percentage rate of response. RESULT: The results indicate that an overwhelming majority of survey responders have a positive attitude and favorable experience with using acupuncture as an alternative modality for chronic pain management. However, our survey responders are mostly from teaching hospitals, suggesting a possible gap between teaching hospitals and other medical facilities (private practice and community hospitals) in utilizing acupuncture for pain management. The lack of insurance coverage and facility for acupuncture treatment are two primary barriers to making acupuncture referrals. CONCLUSIONS: The survey results indicate that acupuncture is considered by many physicians to be a useful alternative modality for chronic pain management.

Altered quantitative sensory testing outcome in subjects with opioid therapy.

Preclinical studies have suggested that opioid exposure may induce a paradoxical decrease in the nociceptive threshold, commonly referred as opioid-induced hyperalgesia (OIH). While OIH may have implications in acute and chronic pain management, its clinical features remain unclear. Using an office-based quantitative sensory testing (QST) method, we compared pain threshold, pain tolerance, and the degree of temporal summation of the second pain in response to thermal stimulation among three groups of subjects: those with neither pain nor opioid therapy (group 1), with chronic pain but without opioid therapy (group 2), and with both chronic pain and opioid therapy (group 3). We also examined the possible correlation between QST responses to thermal stimulation and opioid dose, opioid treatment duration, opioid analgesic type, pain duration, or gender in group 3 subjects. As compared with both group 1 (n=41) and group 2 (n=41) subjects, group 3 subjects (n=58) displayed a decreased heat pain threshold and exacerbated temporal summation of the second pain to thermal stimulation. In contrast, there were no differences in cold or warm sensation among three groups. Among clinical factors, daily opioid dose consistently correlated with the decreased heat pain threshold and exacerbated temporal summation of the second pain in group 3 subjects. These results indicate that decreased heat pain threshold and exacerbated temporal summation of the second pain may be characteristic QST changes in subjects with opioid therapy. The data suggest that QST may be a useful tool in the clinical assessment of OIH.