The metabolic syndrome is related to albuminuria in Type 2 diabetes

AIMS: To determine the relationships between metabolic syndrome (MetS), diabetic nephropathy (DN) and renal function in Type 2 diabetes. METHODS: In a clinic-based cohort of 1314 Type 2 diabetic patients (58% male; age 62 +/- 10 years), we analysed MetS, detected DN and estimated glomerular filtration rate (eGFR). RESULTS: Prevalence of both microalbuminuria and macroalbuminuria were higher in subjects with MetS than in those without. Prevalence of DN (microalbuminuria and macroalbuminuria) increased with the number of MetS components. eGFR was lower in subjects with MetS than in those without (87 +/- 23 vs. 92 +/- 20 ml/min per 1.73 m2; P < 0.001). The lowest eGFR values were found in those with four or more components of the MetS. Prevalence of low eGFR increased with the stage of DN and was affected by MetS only in normoalbuminuric patients. MetS was independently associated with DN, also after adjustment for confounders [odds ratio (OR) 2.82, confidence interval (CI) 1.93, 4.11] and the presence of low eGFR in the model (OR 2.74, CI 1.87, 4.01). Similarly, MetS was a predictor of low eGFR (OR 1.93, CI 1.11, 3.36), but after adjustment for DN, the association was lost. Finally, MetS per se was independently associated with DN, but not with low eGFR after adjustment for all of the individual components of the MetS. CONCLUSIONS: This study suggests a close and independent association between MetS and renal impairment. However, it is unclear whether and to what extent treating MetS by an intensive multifactorial therapeutic approach will prevent or delay progression to renal failure.