(English) Long-term Effects of Dietary Protein Restriction and ACE-inhibitors on Micro-albuminuria in Normotensive Type 1 Diabetics

Diagnostic and Consultative Center „St. Luka" – Sofia *Clinic of Endocrinology, Alexandrov's Hospital – Sofia

 

Abstract:

Potein intake restriction in type 1 diabetes patients with microalbuminuria (MA) has been found to reduce elevated glomerular filtration rate and albuminuria regardless of glycemic control and blood pressure. ACE inhibitors given to normoten-sive individuals also account for delayed progress of diabetic renal damage and blunted increases in MA.

A randomized parallel study is conducted to evaluate the effect of 3-year-long protein restric¬tion and ACE inhibitor treatment on MA in nor¬motensive type 1 diabetes patients. Twenty-four diabetics (10 men and 14 women) are randomly selected, and distributed in groups as follows: low protein diet (group 1), given ACE inhibitor (2), or intensive insulin regimen (3). The mean age of the patients is: 40,5 ± 8,1, 42,2 ± 8,1, and 45,8 ± 13,0 years, respectively for group 1, 2 and 3.

Food intake is assayed by 24-hour diet re¬calls, with the reported protein intake validated by urine urea nitrogen.

After 36-month observation, reported pro¬tein intake is 0,75 g/kg bw in group 1, 0,92 g/kg bw in group 2, and 0,89 g/kg bw in group 3. Albu¬min excretion rate at endpoint: 94,5 /^g/min, 72,0 //g/min, and 83,0 ^g/min for the three groups, re¬spectively – without any significant differences be¬tween the groups. Blood pressure remains stable throughout the study period. Glycemic control, evaluated by HbAlc level: 9,46 ±2,0%, 9,7 ± 2,3%, and 8,2 ± 1/3% respectively, for the three groups.

The patients reported a sufficient reduction of protein intake, but it failed to result in a signifi¬cant MA reduction. Presumably, the patients be¬ing examined were unable to comply with the diet prescribed for a continuous period of time.

The obtained results are in support of the hypothesis that ACE inhibitors reduce MA inde¬pendently of glycemic control.

 

Keywords: microalbuminuria, protein restriction, ACE inhibitors, diabetes mellitus type 1, normotension.