PT - JOURNAL ARTICLE AU - Jeffrey F. Scherrer AU - John E. Morley AU - Joanne Salas AU - James S. Floyd AU - Susan A. Farr AU - Sascha Dublin TI - Association Between Metformin Initiation and Incident Dementia Among African American and White Veterans Health Administration Patients AID - 10.1370/afm.2415 DP - 2019 Jul 01 TA - The Annals of Family Medicine PG - 352--362 VI - 17 IP - 4 4099 - http://www.annfammed.org/content/17/4/352.short 4100 - http://www.annfammed.org/content/17/4/352.full SO - Ann Fam Med2019 Jul 01; 17 AB - PURPOSE African American patients are more likely to experience cognitive decline after type 2 diabetes mellitus onset than white patients. Metformin use has been associated with a lower risk of dementia compared with sulfonylureas. Evidence for whether this association differs by race is sparse.METHODS Veterans Health Administration (VHA) medical record data were obtained for 73,761 African American and white patients aged ≥50 years who used the VHA from fiscal years 2000 to 2015. Patients were free of dementia and diabetes medications during fiscal years 2000 and 2001 and subsequently initiated metformin or sulfonylurea monotherapy. For race and age subgroups, Cox proportional hazards models using propensity scores and inverse probability of treatment weighting to control for confounding were computed to measure the association between metformin vs sulfonylurea initiation and incident dementia.RESULTS After controlling for confounding, among patients aged ≥50 years, metformin vs sulfonylurea use was associated with a significantly lower risk of dementia in African American patients (hazard ratio [HR] = 0.73; 95% CI, 0.6-0.89) but not white patients (HR = 0.96; 95% CI, 0.9-1.03). The strongest magnitude of association between metformin and dementia was observed among African American patients aged 50 to 64 years (HR = 0.6; 95% CI, 0.45-0.81). Among those aged 65 to 74 years, metformin was significantly associated with lower risk of dementia in both races. Metformin was not associated with dementia in patients aged ≥75 years.CONCLUSIONS Metformin vs sulfonylurea initiation was associated with a substantially lower risk of dementia among younger African American patients. These results may point to a novel approach for reducing the risk of dementia in African Americans with type 2 diabetes mellitus.