EFFECTS OF LONG-TERM ENALAPRIL TREATMENT ON PERSISTENT MICROALBUMINURIA IN WELL-CONTROLLED HYPERTENSIVE AND NORMOTENSIVE NIDDM PATIENTS

OBJECTIVE- To determine whether long-term treatment with an angiotensi n-converting enzyme (ACE) inhibitor has a beneficial effect on the uri nary microalbumin excretion and renal function in non-insulin-dependen t diabetes mellitus (NIDDM) patients, enalapril (5 mg/day) was adminis tered for 48 months. RESEARCH ESIGN AND METHODS- Fifty-two patients wi th NIDDM who had persistent microalbuminuria in the range of 20-300 mg /24 h, serum creatinine <106.1 mu M (1.2 mg/dl), supine systolic blood pressure (BP) <150 mmHg, supine diastolic BP <90 mmHg, and HbA(1c) <1 0% were divided into four groups. Twenty-six patients with normotensio n were divided at random into two groups; one group received enalapril (5 mg/day) (NE group), the other did not receive enalapril (NC group) . In the same way, 26 other patients who were already well-controlled with nifedipine (30 mg/day) over a long-term period (4-6 years) were d ivided at random into two groups; one received enalapril (5 mg/day) (H E group), the other did not receive enalapril (HC group). RESULTS- Aft er 48 months, urinary albumin excretion (HE) was markedly reduced in g roup NE from 102.4 X/divided by 1.3 to 55.5 X/divided by 1.3 mg/24 h ( P < 0.005), whereas no significant change occurred in group NC. In the well-controlled hypertensive groups, a significant reduction in UAE o ccurred in group HE (P < 0.05), whereas no significant change occurred in group HC. No changes in creatinine clearance, BP, or blood glucose control were seen during the study.CONCLUSIONS- Treatment with enalap ril for 48 months may have a beneficial effect on the decline of micro albumin excretion in NIDDM patients.