Microalbuminuria and increased plasma prorenin. Prevalence in diabetics followed up for four years.

When urinary albumin excretion was measured by radioimmunoassay, most diabetics excreted more albumin than nondiabetic subjects. Microalbuminuria was defined as an albumin excretion greater than 30 mg/g of urinary creatinine, more than twice the upper limit of normal. Intermittent microalbuminuria was found in 20% of patients with insulin-dependent diabetes mellitus (IDDM) or non-insulin-dependent diabetes mellitus (NIDDM). Continuous microalbuminuria occurred in a similar percentage of patients with NIDDM, but less frequently in patients with IDDM. Rigorous control of glycemia was followed by cessation of microalbuminuria in nearly half of these patients. Microalbuminuria was associated with an increased incidence of other microvascular complications, as well as a distinctly higher plasma prorenin value in IDDM. Hypertension of 160/100 mm Hg or above was accompanied by increased albumin excretion and lower plasma prorenin values than in normotensive diabetics.