PROTEIN-INTAKE AND GLOMERULAR HYPERFILTRATION IN INSULIN-TREATED DIABETICS WITHOUT MANIFEST NEPHROPATHY

Protein intake in relation to glomerular filtration rate (GFR) and uri nary albumin excretion (UAE) has been studied in 96 insulin-treated di abetic patients, 20-40 years of age and without nephropathy. They had diastolic brood pressures (DBP) not exceeding 90 mmHg and a GFR exceed ing -2 SD of the age-related value. They were without medications exce pt for insulin. There were no significant differences in protein intak e between diabetic patients with and without hyperfiltration (1.18 +/- 0.26 g/kg/d vs 1.21 +/- 0.42 g/kg/d, p = 0.75) or between diabetic pa tients with or without increased UAE (1.16 +/- 0.41 g/kg/d vs 1.24 +/- 0.37 g/kg/d, p = 0.37). No relations were found between protein intak e and GFR or UAE in the whole sample, but a positive relation was foun d between UAE and protein intake in patients with increased UAE. Prote in intake correlated with UAE in hyperfiltrators who use tobacco (n = 8, r = 0.85, p = 0.01), but not in non-users (n = 11, r = 0.24, p = 0. 48). In conclusion our findings give no support for a relation between high protein intake and glomerular hyperfiltration in insulin-treated -diabetic patients. However, in contrast to none-users of tobacco, a p ositive relation was found between UAE and protein intake in tobacco u sers with hyperfiltration.