Endothelial function and serum lipids in the course of developing microalbuminuria in insulin-dependent diabetes mellitus

Changed endothelial function and dyslipidemia are features of insulin-dependent diabetes mellitus complicated with clinical nephropathy. The time relationship between the appearance of these abnormalities is however not well known. We have therefore studied the coincidence of microalbuminuria, endothelial dysfunction and dyslipidemia during a 10 year prospective study of 209 insulin-dependent diabetic patients with normal urinary albumin excretion. Twenty-three patients developed progressing microalbuminuria defined as a median urinary albumin excretion > 30 mg/24-h in two consecutive years and a progression rate in albuminuria higher than 5% per year. Thirty patients who remained normoalbuminuric throughout the observation period were randomly selected to obtain a control group with comparable degree of glycaemic control. The mean level of von Willebrand factor before onset of microalbuminuria tended to be higher in patients developing microalbuminuria than in the control group (NS), but there was no increase in von Willebrand factor in the patients who developed microalbuminuria. Total cholesterol did not change, but a significant decrease in high density lipoprotein cholesterol was observed in patients who developed microalbuminuria. In conclusion, the study demonstrated coincidence of microalbuminuria and decreasing high density lipoprotein cholesterol, but no coincidence between onset of microalbuminuria and endothelial dysfunction assessed by von Willebrand factor.