Donepezil treatment in ethnically diverse patients with Alzheimer disease.

OBJECTIVE To compare the outcome of donepezil treatment in ethnically diverse Alzheimer disease (AD) patients with ethnically diverse AD patients who did not receive donepezil. METHODS Patients meeting NINCDS-ADRA criteria for probable or possible AD from a consortium of California sites were systematically followed for at least 1 year in this prospective, observational study. Their treatment regimens, including prescription of donepezil, were determined by their individual physician according to his or her usual criteria. Patients self-identified their ethnicity. RESULTS The 64 ethnically diverse AD patients who completed the study and received donepezil treatment had an average 1-year decline of 2.30 points (standard deviation: 3.9) on the 30-point Mini-Mental State Exam compared with a 1.70-point (standard deviation: 4.2) decline in the 74 ethnically diverse completers who received no donepezil or other anti-AD drugs during the study period. This difference was not statistically significant. The overall Cohen effect size of this treatment-associated difference was estimated at -0.15. After using propensity analyses and other techniques to assess factors that could bias prescribing decisions, the lack of benefits associated with donepezil treatment remained. The lack of donepezil benefits also remained when more traditional analyses were applied to these data. CONCLUSION Ethnically diverse AD patients in this study apparently did not benefit from 1 year of donepezil treatment. These unpromising results are in contrast to modest benefits of donepezil treatment measured in a directly comparable California study involving white non-Latino AD patients.