Association Between Angiotensin-Converting Enzyme Insertion/Deletion Polymorphisms and Frailty Among Chinese Older People

Abstract Objectives Frailty involves complex mechanisms of cumulative decline in several physiological systems and is associated with adverse events that are determined by genetic and environmental factors. It has been reported that angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphisms are associated with human performance. However, the relationships between ACE polymorphisms and frailty are poorly understood. Therefore, we used a Chinese community-dwelling cohort to examine these relationships. Design and setting This study is a part of the Comprehensive Geriatric Assessment and Health Care Service Study, which is a cross-sectional study being conducted in Southwest China. Participants and measurements The participants were grouped into frail, pre-frail, and robust groups according to the revised Fried frailty criteria. Frailty scores were obtained based on the number of frailty items present and used to evaluate the levels of frailty. ACE I/D polymorphisms were detected by polymerase chain reaction using specific primer. Results After the exclusion of participants with missing data, we included 604 community-dwelling Han people (57.9% women, mean age = 70.6 ± 6.8 years). The frequencies of the I/I, I/D, and D/D genotypes were 45.0%, 45.0%, and 10.0%, respectively. The I/D + D/D genotype (D carriers) exhibited higher frailty scores than did the homozygous I/I group (t = −2.07, P  = .039). A greater proportion of the D carriers were classified as frail compared with the homozygous I/I group, but this difference was not statistically significant (15.1% vs 9.9%; χ 2  = −4.57, P  = .102). The I/I genotype was associated with a lower frailty score and was significantly associated with reduced risk of prevalent frailty compared with the D-carrying genotypes (adjusted odds ratio 0.689, 95% confidence interval 0.493–0.965; P  = .030). Conclusions The I/I ACE genotype is associated with a lower risk of frailty and a lower frailty level relative to the D-carrying genotypes among older Han people.