The Klotho gene G-395A polymorphism and metabolic syndrome in very elderly people.

backgroundTo investigate the possible association of the Klotho G-395A polymorphism and metabolic syndrome (MetS) among a population of Chinese nonagenarians and centenarians.

methodsSubjects were from the Project of Longevity and Aging in Dujiangyan (PLAD). The genotyping of G-395A (rs1207568) in the promoter region of the Klotho gene was performed using the TaqMan allelic discrimination assay. MetS was diagnosed according to the International Diabetes Federation criteria.

resultsWe included 695 subjects aged 93.5 ± 3.2 years. G and A allele frequencies were 0.852 and 0.148, respectively. In the whole population, the frequency of MetS was 10.8% and 5.9% in the GG and GA + AA genotype group, respectively (p = 0.004). The -395A allele carriers had significantly lower risk of MetS in the whole population (odd ratio [OR] 0.50, 95% confidential interval [CI] 0.25 to 0.98) and in women (OR 0.51, 95% CI 0.24 to 0.97), but not in men (OR 0.42, 95% CI 0.05 to 3.85). In the whole population and women, the relationship between the Klotho G-395A SNP and MetS might due to its influence on high blood pressure (OR 0.48, 95% CI 0.34 to 0.67; OR 0.47, 95% CI 0.31 to 0.71, respectively) and hypertriglyceridemia (OR 0.66, 95% CI 0.39 to 0.95; OR 0.54, 95% CI 0.31 to 0.98, respectively). In men, this relationship might due to its influence on high blood pressure (OR 0.47, 95% CI 0.25 to 0.90) and low HDL-C (OR 0.69, 95% CI 0.27 to 0.93).

conclusionsThe -395A allele carriers of the Klotho gene were correlated with lower risk of MetS among Chinese nonagenarians and centenarians, especially in women.