O rim na síndrome metabólica

Abstract

Introduction: Studies concerning the influence of the metabolic syndrome on renal hemodynamics in non-diabetic patients are scarce. Objectives: The objective of this study was to evaluate metabolic and renal parameters in patients with metabolic syndrome before and after weight loss. Material and methods: Thirty five patients with metabolic syndrome were evaluated before and after 3 months on a hypocaloric diet in order to achieve at least 5% of body weight loss. At baseline as well as after 3 months on diet, samples for fasting glucose, glucose 2 hours after a 75g oral glucose load, insulin, uric acid and lipid profile were collected. Among renal parameters, microalbuminuria and creatinine clearance were measured before and after acute protein overload to estimate the renal functional reserve. Results: Two groups were constituted: patients that reached the goal of weight loss (responder group, n=14) and patient that did not lose weight (non-responder group, n=22). In the responder group, there was reduction of the microalbuminuria from 109±123.2 mg/24h (median=163 mg/24h) to 10±6.1 mg/24 h (median=10.4 mg/24h), in the basal period and after weight loss, respectively (p=0.01). The creatinine clearance was 122±66.5 ml/min, in the basal period and 117±45.0ml/min, after acute protein overload (p=0.443). After weight loss, these values were 93±35.6 ml/min and 96±41.7ml/min, before and after acute protein overload, respectively (p=0.776). After weight loss besides the significant reduction on basal creatinine clearance (122±66.5 ml/min vs 93±35.6 ml/min) (p=0.001), there were increase in HDL cholesterol levels from 42.8±11.7 to 51.8±10.8 (p=0.039), and reduction in triglycerides levels from 189±79.4 mg/dl to 142±77.8 mg/dl (p=0.031), uric acid from 5±1.2 mg/dl to 4±1.1 mg/dl (p=0.057) and HOMA-IR, from 3.0±2.1 to 1.6±0.7, in the baseline and after weight loss, respectively (p=0.057). In the non-responder group, microalbuminuria was 78±79 mg/24 h (median=174 mg/24 h) and 78±86 mg/24 h (median=97 mg/24 h), in the baseline and after three months (p=0.99). The baseline creatinine clearance was 102±29.9 ml/min and 96±24.2ml/min (p=0.125) before and after acute protein overload, respectively. After 3 months, creatinine clearance before and after acute protein overload were 98±31.8 ml/min and 86±31.1 ml/min, respectively (p=0.355). Differently from responders, in non-responders group, the baseline creatinine clearance did not modify throughout the study (102±29.9 ml/min vs 98±31.8 ml/min) (p=0.95). In the same way, the metabolic parameters, HDL cholesterol (43±8.4 vs. 41±9.8 mg/dl), triglycerides (206±98.0 vs. 224±140.5 mg/dl), uric acid (5±0.9 vs. 5±1.2 mg/dl) and HOMA-IR (3.4±2.8 vs. 2.3±2.6) were similar at the baseline and after 3 months on hypocaloric diet. Conclusion: Non-diabetic individuals with metabolic syndrome presented high prevalence of microalbuminuria and glomerular hyperfiltration, which were attenuated by weight loss.