Compared to the lower cystatin C levels (<1.36 mg/L), the highest cystatin C level (≥1.36 mg/L) was associated with older age, higher prevalence among male patients, and higher incidence of the coexistent conditions, such as chronic pulmonary disease, hypertension, diabetes, cardiovascular disease, cerebrovascular disease, and CKD (all P values for trend < 0.05, Table 1). The gene discussed is CST3; the disease is chronic kidney disease.