Association between serum α-klotho level and the prevalence of heart failure in the general population

Heart failure is a major cause of global morbidity and mortality. Studies in laboratory animals have shown the direct protective effects of α-klotho on the cardiovascular system although it has limited expression in the heart. The association between α-klotho and cardiovascular disease is still controversial in different clinical studies. We designed a cross-sectional study in order to investigate the association between serum α-klotho level and the prevalence of heart failure in the American general population. The data were obtained from the National Health and Nutrition Examination Survey (NHANES), which included 11 271 participants aged 40-80 years. Serum α-klotho level was examined by enzyme-linked immunosorbent assay and divided into four quartiles for further analysis. Heart failure status was obtained from self-reported questionnaires. To estimate the association between α-klotho level and prevalence of heart failure, multivariate logistic regression analyses were conducted. Interaction and stratified analyses were performed to evaluate the potential modifiers. After adjusting for multiple covariates, a per-standard deviation increase in serum α-klotho level was associated with a decrease in prevalence of heart failure [odds ratio (OR): 0.76, 95% confidence interval (CI): 0.68-0.85). The ORs for participants in quartiles 2 to 4 were 0.77 (95% CI: 0.58-1.01), 0.70 (95% CI: 0.52-0.93) and 0.71 (95% CI: 0.53-0.95), respectively, compared with those in quartile 1. Stratified analysis revealed significant gender and racial differences. We revealed an independent association between serum α-klotho level and the prevalence of heart failure in the American general population. The association was not always consistent and varied according to gender and race.