The number of patients who needs for dialysis
therapy is increasing rapidly among the older population. Although control of
hypertension can delay or arrest the progression of
renal failure, there are lacking of studies about
antihypertensive treatment of
chronic renal failure in the elderly. We have studied the effects of treating
hypertension with a
calcium antagonist,
benidipine, on renal function and blood pressure in 58 patients (mean age: 71 +/- 9) with
hypertension and
chronic renal insufficiency (the levels of
creatinine ranging from 1.5 to 4.0 mg/dl). The underlying disease included glomerulopathies (in 33),
diabetic nephropathy (in 15), and other causes (in 10). Forty two patients who had been treated with other
antihypertensive drugs other than
angiotensin converting enzyme (
ACE) inhibitors,
antihypertensive drugs were withdrawn 2 weeks before the entry. At the entry, patients should have sitting systolic blood pressure (SBP) of above 160 mmHg and diastolic blood pressure (DBP) of above 90 mmHg. In total, both SBP and DBP decreased from 169/95+/-12.5/8.9 to 148/81+/-16.1/8.0 mmHg (p<0.001) with remaining the serum
creatinine levels from 2.2+/-0.8 vs 2.4+/-1.3 mg/dl (P>0.05). Retrospective analysis revealed that in 4 of 4 patients treated with
benidipine and 2 of 3 patients with
benidipine and
ACE inhibitors with systolic blood pressure more than 160 mmHg at the end of the study, the levels of serum
creatinine increased from 2.5+/-0.3 to 2.8+/-0.4 with significance (P<0.05). If systolic blood pressure was reduced less than 159 mmHg, 38 of 48 patients did not show any deterioration of renal function. Compared to the significance of SBP in preserving renal function, DBP did not associate with the changes in renal function. No patients died during the study. One patient had
transient ischemic attack and one patient had
stroke in
benidipine treated group. One patient had
angina pectoris in
benidipine-
ACE inhibitors treated group. The results of our trial seem to give some support for the idea that long-acting
calcium antagonists such as
benidipine are renoprotective through reduction of SBP in the elderly people with
hypertension and
chronic renal insufficiency. However, if systolic blood pressure was not reduced below 160 mmHg throughout a year, the substantial declines in renal function would be expected.