[Evaluation of the tolerance and effectiveness of Diltiazem LP 300 mg in hypertensive patients with chronic renal insufficiency].

31 male and female patients, between the ages of 18 and 65 years, presenting mild-to-moderate hypertension (DBP between 95 and 114 mmHg) and stable chronic renal failure (creatinine clearance between 60 and 25 ml/min) after a preinclusion placebo phase were included in a multicentre open study designed to evaluate the clinical, electrocardiographic and laboratory safety, as well as the antihypertensive efficacy of Diltiazem 300 mg Retard, as monotherapy for 3 months, or combined with a diuretic (furosemide) or angiotensin converting enzyme inhibitor (captopril) for 45 days. After an 8-day placebo run-in period, the study consisted of a 45-day phase of strict monotherapy with Diltiazem 300 mg Retard, followed by a final 45-day phase during which either monotherapy was continued (if safety was satisfactory and supine DBP < or = 90 mmHg), or two-agent combination therapy was instituted (when supine DBP was between 91 and 115 mmHg), 6 clinical evaluations were performed during the 3 months of this trial. Overall, 21 patients (mean age: 50 +/- 14 years) completed the study until the 3rd month: 13 remained on monotherapy, and 8 required two-agent combination therapy. Supine and standing systolic and diastolic blood pressures and heart rate were significantly decreased. The number of responding patients controlled (supine DBP < or = 90 mmHg) progressed between D10 (40%) and D90 (57%). The observed adverse events and reasons for drop-outs from the trial for adverse events were mostly related to the vasodilator effects of Diltiazem. The cardiac safety was good, with no significant variation of the PR interval on the ECG (0.15 +/- 0.03 sec on D-8, 0.17 +/- 0.02 sec on D90). No marked modification of blood and urinary laboratory constants (serum electrolytes, blood glucose, liver function tests) was observed during this trial. Renal function, evaluated by creatinine clearance, was not altered by treatment (40.5 +/- 15.2 ml/min on D0, 41.7 +/- 16.9 ml/min on D90). Overall, this study confirmed the good clinical, laboratory and electrocardiographic safety as well as the antihypertensive efficacy of Diltiazem 300 mg Retard administered as monotherapy for 3 months or possibly in combination for 45 days, in hypertensive patients with chronic renal failure.