RELATIONSHIP BETWEEN FAT INTAKE AND GLOMERULAR-FILTRATION RATE IN NORMOTENSIVE INSULIN-DEPENDENT DIABETIC-PATIENTS

Glomerular hyperfiltration is a candidate marker for diabetic nephropa thy in insulin-dependent diabetic patients since it can reflect elevat ed glomerular capillary pressure, a cause of glomerulosclerosis. We st udied the potential contribution of several dietary components to glom erular hyperfiltration during a cross-sectional study of 110 consecuti ve normotensive, non-proteinuric insulin-dependent patients with respe ct to glomerular filtration rate (GFR) and food intake. GFR was measur ed using the Cr-51-EDTA plasma disappearance technique. Glomerular hyp erfiltration was defined as GFR > 137 ml.min(-1) 1.73 m(-2) (mean + 2 SD of age-matched healthy controls). Food intake was recorded with a c omputer-assisted programme. Thirteen patients displaying glomerular hy perfiltration ingested more protein (1.60 +/- 37 vs 1.38 +/- 0.34 g.kg (-1) body weight.day(-1); p = 0.032) and more fat (1.70 +/- 0.54 vs 1. 39 +/- 0.44 g.kg(-1) body weight.day(-1); p = 0.022) than other subjec ts, al though their total energy intakes were similar. Univariate regr ession ana lysis showed that GFR was positively related to both protei n (r = 0.28; p = 0.003) and fat (tau = 0.25; p = 0.007) intakes and ne gatively related to age (r = -0.29; p = 0.002). Stepwise multivariate regression analysis indicated 2 independent determinants for GFR: age (F = 15.26) and fat intake (F = 13.15). Excess fat intake may contribu te to glomerular hyperfiltration in insulin-dependent diabetes.