Apolipoprotein E ε4 prevalence in Alzheimer's disease patients varies across global populations: a systematic literature review and meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of observational prevalence studies
PubMed 21124030 · doi:10.1159/000321984
What was done
A systematic literature review and meta-analysis were conducted to evaluate the prevalence of the apolipoprotein E ε4 (APOE4) allele among patients diagnosed with Alzheimer's disease (AD) across distinct geographic and racial/ethnic groups. Specific databases, search dates, and the total count of included studies were not reported in the abstract.
What was found
APOE4 carrier prevalence differed significantly by geographic recruitment region (all comparisons p < 0.05): - Asian communities: 37% - Southern European/Mediterranean communities: 43% - North American communities: 58% - Northern European communities: 64% Estimates were also significantly influenced by study design and case definitions.
Why it matters
The findings confirm that the genetic epidemiology and attributable risk of APOE4 in Alzheimer's disease vary substantially worldwide, reflecting background general population allele frequencies.
Limits
The abstract omits total sample size (both study count and participant totals), confidence intervals, and specific database search criteria. Significant heterogeneity across studies was driven by differences in study design and AD case definitions.
Cited by
- contradicts Between 65% and 80% of individuals diagnosed with Alzheimer's disease carry at least one APOE4 allele.