Reduced klotho is one risk factor for the occurrence and development of coronary artery disease in elderly people

Background: S-Klotho has been deemed as a protein related to human longevity. However no studies have specially examined the relationship between serum levels of Klotho and coronary artery disease (CAD) in the people more than 70 years old. Hypothesis: We proposed that low plasma klotho concentrations would be independently associated with CAD in elderly people. Methods: 315 consecutive patients who had at least one coronary angiography examination were included in our study. All the patients were older than 65 years old. Their coronary artery condition, blood pressures, s-Klotho concentration, liver function, renal function and thyroid function were evaluated at their first visits. Their readmissions because of CAD were recorded during their follow-up. Logistic regression analysis was used to select the risk factors for CAD readmission. Results: The 315 consecutive patients were divided into primary cohort (200 cases) and validation cohort (115 cases) randomly. The final model included 6 significant variables, which were a-klotho, CAD grade, creatinine, HDL, hemoglobin and uricacid. All these variables were then used to build a risk score in terms of the prediction of incidence of CAD. The ROC curve for the weighted score showed good discriminant power with a c statistic of 0.894 (95% CI: 0.8237-0.9637). Conclusions: Our study is the first time reporting that the elderly patients with lower level of s-klotho concentrations have a higher risk of readmission because of CAD.