Candace S Brown1, Gloria A Bachmann, Jim Wan, David C Foster. 1. Departments of Clinical and Translational Science and Preventive Medicine, University of Tennessee Health Science Center, Memphis, Tennessee; the Department of Obstetrics, Gynecology and Reproductive Sciences, Rutgers-Robert Wood Johnson Medical School, New Brunswick, New Jersey; and the Department of Obstetrics and Gynecology, University of Rochester School of Medicine and Dentistry, Rochester, New York.
Abstract
OBJECTIVE: To evaluate whether extended-release gabapentin is more effective than placebo among women with vulvodynia. METHODS: In a multicenter double-blind, placebo-controlled randomized crossover trial, gabapentin (1,200-3,000 mg/d) was compared with a placebo. The primary outcome was mean pain intensity (0, no pain at all to 10, worst pain ever) on the tampon test (a standardized tampon insertion and removal test used as a surrogate marker for dyspareunia) during the last 7 days of the maintenance phase. Secondary outcomes included sexual intercourse pain and daily pain. A sample size of 53 provided 90% power to detect a 1-point reduction on the tampon test (.05 level, two-sided) between the two treatment phases. RESULTS:From August 2012 to January 2016, 230 women were screened at three academic institutions and 89 (mean age 37 years; 65% black) were randomized: 45 to gabapentin first and then placebo and 44 to placebo first and then gabapentin. Tampon test pain with gabapentin was not different compared with the placebo (adjusted mean 4.0, 95% CI 3.0-4.9 vs 4.3, 95% CI 3.4-5.2, difference -0.3, 95% CI -0.7 to 0.0; P=.07). Gabapentin also did not improve pain over placebo for sexual intercourse pain (adjusted mean 3.9, 95% CI 2.4-5.3 vs 4.0, 95% CI 2.5-5.4, difference -0.1, 95% CI -0.9 to 0.6; P=.76) and daily pain (adjusted mean 2.7, 95% CI 1.8-3.6 vs 2.9, 95% CI 2.0-3.8, difference -0.2, 95% CI -0.5 to -0.2; P=.36). Subset analyses found that longer pain duration and oral contraceptive nonuse were associated with minimal improvement in tampon test pain with gabapentin. CONCLUSION: In this cohort, extended-release gabapentin, as compared with a placebo, did not reduce tampon test pain. These data do not support the recommendation of gabapentin alone as treatment for vulvodynia. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT01301001.
RCT Entities:
OBJECTIVE: To evaluate whether extended-release gabapentin is more effective than placebo among women with vulvodynia. METHODS: In a multicenter double-blind, placebo-controlled randomized crossover trial, gabapentin (1,200-3,000 mg/d) was compared with a placebo. The primary outcome was mean pain intensity (0, no pain at all to 10, worst pain ever) on the tampon test (a standardized tampon insertion and removal test used as a surrogate marker for dyspareunia) during the last 7 days of the maintenance phase. Secondary outcomes included sexual intercourse pain and daily pain. A sample size of 53 provided 90% power to detect a 1-point reduction on the tampon test (.05 level, two-sided) between the two treatment phases. RESULTS: From August 2012 to January 2016, 230 women were screened at three academic institutions and 89 (mean age 37 years; 65% black) were randomized: 45 to gabapentin first and then placebo and 44 to placebo first and then gabapentin. Tampon test pain with gabapentin was not different compared with the placebo (adjusted mean 4.0, 95% CI 3.0-4.9 vs 4.3, 95% CI 3.4-5.2, difference -0.3, 95% CI -0.7 to 0.0; P=.07). Gabapentin also did not improve pain over placebo for sexual intercourse pain (adjusted mean 3.9, 95% CI 2.4-5.3 vs 4.0, 95% CI 2.5-5.4, difference -0.1, 95% CI -0.9 to 0.6; P=.76) and daily pain (adjusted mean 2.7, 95% CI 1.8-3.6 vs 2.9, 95% CI 2.0-3.8, difference -0.2, 95% CI -0.5 to -0.2; P=.36). Subset analyses found that longer pain duration and oral contraceptive nonuse were associated with minimal improvement in tampon test pain with gabapentin. CONCLUSION: In this cohort, extended-release gabapentin, as compared with a placebo, did not reduce tampon test pain. These data do not support the recommendation of gabapentin alone as treatment for vulvodynia. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT01301001.
Authors: Gloria A Bachmann; Candace S Brown; Nancy A Phillips; Leslie A Rawlinson; Xinhua Yu; Ronald Wood; David C Foster Journal: Am J Obstet Gynecol Date: 2018-10-24 Impact factor: 8.661