Severe Reduction of Renal Function in Hypertensives and/or Diabetics Induced by Angiotensin-Converting Enzyme Inhibitors

Lazaro Gotloib, MD, Department of Nephrology, Central Emek Hospital, 18101 Afula (Israel) Dear Sir, Some clinical studies postulated that angiotensin-converting enzyme inhibitors (ACEI) alone or in combination with diuretics have a renal protective effect in hypertensive patients with either moderately or severely impaired renal function [ 1 ] as well as in insulin-dependent diabetics with ne-phropathy [2]. Even though some investigators reported detrimental effects of ACEI upon renal function in diabetics [3] and in patients with serum creatinine levels > 1.5 mg/dl [4], other authors postulated that these drugs can be safely administered in both clinical situations [5]. The purpose of this report is to present 14 patients referred to our clinic because of mild to severe renal failure which developed within approximately 10 weeks after starting therapy with ACEI. The observations were made on 10 male and 4 female patients with a mean age of 68.21 ± 12.09 years, all of them with a history of arterial hypertension for a mean period of 14 ± 9 years; 6 patients also suffered from insulin-dependent diabetes for long periods oftime(mean23 ± 8 years). The patients showed high mean serum creatinine levels (table 1), and even though the blood pressure was effectively controlled (table 1) by using different combinations of drugs like αmethyldopa, prazosin hydro-chloride, nifedipine, and ß-blockers with thiazides, this therapy was changed to ACEI, the main goal being to delay the deterioration of the kidney function. The mean dosage of captopril was 41.07 ± 20.04 (range 12.5-75) mg/day in 7 patients, whereas that of enalapril was 18.60 ± 10.30 (range 10-40) mg/day in the other 7. Diuretics (thiazides or furosemide) were prescribed to all patients. This therapy was maintained for periods ranging from 2 to 10 (mean ± SD 3.4 ± 0.9) weeks, when patients were referred to our clinic because of significantly higher levels of serum creatinine (table 1). Hyperkalemia was detected in 10 cases. Dialysis was started in 2 patients. One of them had a partial recovery of the renal function (serum creatinine 398 μmol/ 1), whereas the other one started CAPD. Three months after interrupting ACEI, the mean serum creatinine levels remained significantly higher than those observed when using the other antihypertensive drugs. The blood pressure did not significantly change with either therapeutic approach (table 1).