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

Background: 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.

Methods: 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.

Results: 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.

Conclusion: 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.