Are Patients Who Have Metabolic Syndrome without Diabetes at Risk for Developing Chronic Kidney Disease? Evidence Based on Data from a Large Cohort Screening Population

Recently, metabolic syndrome (MS) was suggested to be an independent risk factor for chronic kidney disease (CKD). This study explored the relationship between MS and risk for development of CKD that is independent of diabetes. The study population consisted of 4607 adult (age >18 yr) individuals who did not have diabetes or CKD at baseline and were successfully followed for 3 yr in the Tehran Lipid and Glucose Study, a prospective, population-based study of risk factors for atherosclerosis and diabetes. Individuals with and without MS at baseline were compared regarding development of new CKD. A total of 1010 (21.9%) individuals met criteria for MS at baseline. During the follow-up, 38 (3.4%) individuals in MS group and 73 individuals (2.0%) of 3590 people in non-MS group developed CKD (OR = 1.88, 95% CI; 1.26-2.8). After exclusion of individuals with hypertension at baseline (n = 798), 406 people (10.7%) were defined as having MS. After follow-up, 62 (1.82%) people in the MS group and eight (1.98%) people in non-MS group developed CKD (OR = 0.925, 95% CI; 0.446-1.917; P = 0.844). The results of this study suggest that MS is a cluster of multiple risk factors, and, as a cluster, it is a significant risk for CKD. The risk of MS for developing CKD is highly affected by the presence of diabetes and hypertension, and it seems that clustering of individual risk factors is more plausibly associated with risk for developing CKD than a unique biologic phenomenon.