Potential ethnic modifiers in the assessment and treatment of Alzheimer's disease: challenges for the future.
OBJECTIVE
Despite numerous clinical trials, it is unknown whether ethnicity affects treatment response to cognitive enhancers in Alzheimer's disease (AD). There is convincing evidence of ethnic and genetic variability in drug metabolism. This article reviews the available data on ethnicity in clinical trials for AD to answer two questions: (1) what are the challenges to diagnose and treat AD across different ethnic groups, and (2) are there differences in response to pharmacologic interventions for AD across these different ethnic groups?


METHODS
Available data from Alzheimer's Disease Cooperative Study (ADCS) randomized controlled clinical trials and from randomized controlled industry-sponsored trials for four cognitive enhancers (donepezil, galantamine, rivastigmine and sabeluzole) were pooled to assess the numbers of non-Caucasian participants.


RESULTS
The participation of ethnic minority subjects in clinical trials for AD was dependent on the funding source, although Caucasian participants were over-represented and non-Caucasian participants were under-represented in the clinical trials. Because of the low participation rate of ethnic minorities, there were insufficient data to assess any differences in treatment outcome among different ethnic groups. Strategies to improve diversity in clinical trials are discussed.


CONCLUSIONS
Greater participation of ethnically diverse participants in clinical trials for AD would generate additional information on possible differences in metabolism, treatment response, adverse events to therapeutic agents, and could foster the investigation of genetic variability among ethnic groups.
Faison
Warachal E
WE
Alzheimer's Research and Clinical Programs, Neurosciences Department, Medical University of South Carolina, Charleston, South Carolina 29406, USA. faison@musc.edu
Schultz
Susan K
SK
Aerssens
Jeroen
J
Alvidrez
Jennifer
J
Anand
Ravi
R
Farrer
Lindsay A
LA
Jarvik
Lissy
L
Manly
Jennifer
J
McRae
Thomas
T
Murphy
Greer M
GM
Olin
Jason T
JT
Regier
Darrel
D
Sano
Mary
M
Mintzer
Jacobo E
JE
D000368:Aged; D000544:Alzheimer Disease / Q000175:diagnosis / Q000188:drug therapy / Q000208:ethnology*; D003431:Cross-Cultural Comparison; D000077265:Donepezil; D005006:Ethnicity / Q000523:psychology* / Q000706:statistics & numerical data; D005702:Galantamine / Q000627:therapeutic use; D006801:Humans; D007189:Indans / Q000627:therapeutic use; D018697:Nootropic Agents / Q000627:therapeutic use*; D048448:Phenylcarbamates / Q000627:therapeutic use; D010880:Piperidines / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data*; D000068836:Rivastigmine; D013844:Thiazoles / Q000627:therapeutic use; D044465:White People / Q000523:psychology* / Q000706:statistics & numerical data
D007189:Indans; D018697:Nootropic Agents; D048448:Phenylcarbamates; D010880:Piperidines; D013844:Thiazoles; D005702:Galantamine; D000077265:Donepezil; C055163:sabeluzole; D000068836:Rivastigmine