Association Between Gabapentin Receipt for Any Indication and Alcohol Use Disorders Identification TestConsumption Scores Among Clinical Subpopulations With and Without Alcohol Use Disorder

BackgroundCurrent medications for alcohol use disorder (AUD) have limited efficacy and utilization. Some clinical trials have shown efficacy for gabapentin among treatment-seeking individuals. The impact of gabapentin on alcohol consumption in a more general sample remains unknown. MethodsWe identified patients prescribed gabapentin for 180 consecutive days for any clinical indication other than substance use treatment between 2009 and 2015 in the Veterans Aging Cohort Study. We propensity-score matched each gabapentin-exposed patient with up to 5 unexposed patients. Multivariable difference-in-difference (DiD) linear regression models estimated the differential change in Alcohol Use Disorders Identification TestConsumption (AUDIT-C) scores during follow-up between exposed and unexposed patients, by baseline level of alcohol consumption and daily gabapentin dose. Analyses were stratified by AUD history. Clinically meaningful changes were a priori considered a DiD 1 point. ResultsAmong patients with AUD, AUDIT-C scores decreased 0.39 points (95% confidence interval [CI] 0.05, 0.73) more among exposed than unexposed patients (p<0.03). Potentially clinically meaningful differences were observed among those with AUD and exposed to 1,500 mg/d (DiD 0.77, 95% CI 0.15, 1.38, p<0.02). No statistically significant effects were found among patients with AUD at doses lower than 1,500mg/d or baseline AUDIT-C 4. Among patients without AUD, we found no overall difference in changes in AUDIT-C scores, nor in analyses stratified by baseline level of alcohol consumption. ConclusionsPatients exposed to doses of gabapentin consistent with those used in clinical trials, particularly those with AUD, experienced a greater decrease in AUDIT-C scores than matched unexposed patients.