No abstract

This study suggests that long-term dietary protein restriction beneficially reduces albuminuria and renal hemodynamics in IDDM patients with mildly elevated albuminuria. Systemic BP counteracts these effects even in the absence of hypertension. Suboptimal compliance limits diet efficacy.

All recipes contained larger amounts of allergenic foods than previously validated. These recipes increase the range of validated recipes for use in DBPCFCs in adults and children.

Diabetic nephropathy is one of the most serious complications of diabetes mellitus. Nephropathy develops in approximately 35 % of diabetic patients [1].Preventive measures include good metabolic control and rigorous antihypertensive treatment, preferably by renin-angiotensin system (RAS) blocking agents [2]. Early abnormalities preceding overt nephropathy include microalbuminuria, a rise in blood pressure and an increase in intraglomerular pressure [3,4]. Volume expansion is probably relevant in these processes because renal sodium excretion is known to be blunted in diabetic patients [5,6,7,8,9], an effect that might be mediated by the sodium retaining effects of insulin [10,11].Considering the abnormalities in extracellular volume, dietary sodium restriction would seem a logical form of treatment. However, low sodium intake acti- Diabetologia (2002) Abstract Aims/hypothesis. Type I (insulin-dependent) diabetes mellitus is associated with an increased extracellular volume. Sodium restriction might seem a logical form of treatment but data on its renal effects is conflicting. We therefore studied the effects of sodium restriction on renal haemodynamics in uncomplicated Type I diabetes mellitus. Methods. Uncomplicated Type I diabetic patients (n = 24) and matched control subjects (n = 24) were studied twice in random order: after a week of 50 mmol or after 200 mmol sodium intake, respectively. The diabetic patients were studied under normoglycaemic clamp conditions. Glomerular filtration rate and effective renal plasma flow were measured as the clearances of iothalamate and hippuran, respectively. Results. During liberal sodium intake, glomerular filtration, effective renal plasma flow and filtration fraction were similar between the diabetic patients and the control subjects. Sodium restriction decreased the effective renal plasma flow in both groups, whereas glomerular filtration rate only decreased in the control subjects. Consequently, in the diabetic patients, the filtration fraction was increased on low sodium (4.1 8.4 %, p < 0.05 vs liberal sodium). As a consequence, filtration fraction (24.0 2.6 vs 22.1 2.0 %, p < 0.05) and glomerular filtration (119 14 vs 110 13 ml/min, p < 0.05) were higher in the diabetic patients than in the control subjects during sodium restriction. Conclusion/interpretation. Short-term moderate sodium restriction induces relative hyperfiltration in uncomplicated Type I diabetes. This could indicate an increased intraglomerular pressure. Sodium restriction could be an unfavourable preventive approach in diabetes mellitus but its long-term effects are not known. [Diabetologia (2002) 45:535±541]