Equivalent Reduction of Proteinuria in Hypertensives by either Nifedipine GITS or Enalapril: Disparate Effects on Neurohormones and Ambulatory Blood Pressure and the Influence of Salt

Abstract

Objective: We compared the efficacy of two classes of antihypertensive therapy on ambulatory blood pressure control and proteinuria in patients with hypertension. Furthermore, we determined the effects of the interaction of these therapies on neurohormonal activation and of the patients’ ambient sodium intake on the outcomes. Methods: Sustained-release nifedipine (nifedipine gastrointestinal therapeutic system, GITS) 30-120 mg/day was compared in a double-blind sequential randomized placebo-controlled trial with enalapril 5-30 mg/day regarding office and 24-hour blood pressure control, plasma renin activity, noradrenaline and adrenaline levels and 24-hour urinary protein and sodium in 46 elderly nondiabetic hypertensive patients in a 16- to 18-week trial. Results: Both nifedipine GITS and enalapril controlled ambulatory blood pressure during the day and at peak effect. Nifedipine GITS controlled ambulatory blood pressure during the early morning surge and at night time as well. Nifedipine GITS increased plasma renin activity and noradrenaline by 50 and 20%, respectively, compared to the 150 and 0% change produced by enalapril. Both nifedipine GITS and enalapril reduced proteinuria by 37%. Patients had increasing levels or proteinuria proportional to higher ambient sodium intake (r = 0.48; p < 0.01). This effect was accentuated during nifedipine GITS therapy as compared to enalapril. Conclusion: Nifedipine GITS was superior to enalapril in controlling ambulatory blood pressure, but they were equivalent in reducing proteinuria (37%). They had disparate effects on neural activation and the duration of action. Raised protein excretion appears to be associated with raised sodium intake. This was apparent especially during nifedipine XL therapy.

Microalbuminuria in essential hypertension

“…[25][26][27][28] These conflicting results could be due to the different actions of the short-acting and the long-acting (GITS) formulation of this drug. In a first investigative series we evaluated the effect of short-acting nifedipine and captopril fixed doses on UAE.…”

Sympatholytic therapy in primary hypertension: a user friendly role for the future

“…Thus, with both verapamil and diltiazem, there may be an initial increase in sympathetic nervous system tone, but shortly thereafter, there is a reduction of noradrenergic tone. 15 On the other hand, the dihydropyridine, nifedipine, appears to yield a reflex increase in neural tone, after both immediate 16 and sustained 17 release preparations. Unlike the other dihydropyridine calcium antagonists, amlodipine appears to have less stimulating properties on the central and peripheral sympathetic nervous system (SNS).…”