Additional effect in reduction of albuminuria due to the combination therapy of angiotensin-converting-enzyme inhibitor and angiotensin II type 1 receptor blocker in type 2 diabetic patients with the angiotensinogen 235T allele

Abstract

    We evaluated the combination therapy of angiotensin-converting-enzyme inhibitor (ACE-I) and angiotensin II type 1 receptor blocker (ARB) offered an additional effect in reduction of albuminuria in type 2 diabetic patients with angiotensinogen (AGT) M235T polymorphism. The study subjects were type 2 diabetic patients with nephropathy who were attending Hirosaki University Hospital. Fifteen patients with 235T allele (TT genotype 9, MT genotype 6) were evaluated who had diabetic nephropathy in stage 2 or 3 and already treated with ACE-I. Each patient administrated ARB (20-40 mg of termisartan) in addition to ACE-I for 16 weeks as the combination therapy. The addition of termisartan induced a significant reduction in systolic blood pressure (BP) of 14.0 mmHg and diastolic BP of 5.4 mmHg. The urinary albumin-creatinine ratio (ACR) was also reduced to 48.9 %. There was no significant correlation between the reduction rate of ACR and the antihypertensive response of systolic blood pressure (BP) (rs = 0.1277) and of diastolic BP (rs = 0.1420) by the addition of termisartan. These results indicated that the combination of ACE-I and ARB had an additional effect on urinary albumin excretion in type 2 diabetic patients with AGT 235T allele.