Conditions: Microalbuminuria
Keywords: Microalbuminuria Carotid intima media thickness Endothelial dysfunction Renin angiotensin system Diabetic nephropathy
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 46
Healthy volunteers: no

Brief summary:
The objective of the study is to assess the effect of standard versus aggressive inhibition of the renin-angiotensin system (RAS)in type 2 diabetic patients with microalbuminuria (MA) on; a)progression of microalbuminuria, b)estimated glomerular filtration rate (eGFR), c)endothelial dysfunction (measured by post-hyperemia arterial tonometry) and d)the slowing of the progression of atherosclerotic disease (measured by carotid intima media thickness \[CIMT\]).

Detailed description:
Diabetic patients with confirmed MA (50-300 mg albumin per g creatinine) on a morning spot urine sample were entered into a one to three month run-in phase before randomization. (50 mg/g was used as the lower limit to allow room for improvement to reach normal.) Since hypertension and uncontrolled hyperglycemia will cause MA, blood pressure (BP) and hemoglobin A1c (AIC) levels were reduced to \<130/80 mm Hg and \<8.0%, respectively, during this period. All patients had been on various doses of an angiotensin converting enzyme inhibitor (ACE-I) which were reduced to 10 mg benazepril and BP controlled with other classes of anti-hypertensive drugs (except for angiotensin receptor blockers \[ARB's\]). Glycemia was treated with intensification of their current therapy. MA and BP were measured monthly.

When goal levels of BP and AIC were achieved and MA was still present, patients were randomized to either low dose RAS inhibition (10 mg benazepril) (Standard) or aggressive inhibition of the RAS (Aggressive). MA continued to be measured monthly and the progressive increase in doses of an ACE-I and an ARB was as follows. Benazepril (the ACE-I) - 10 mg to 20 mg to 40 mg to adding losartan (the ARB) -25 mg to 50 mg to 100 mg to increasing benazepril to 80 mg with the goal of returning albumin excretion to normal. Other classes of drugs were reduced as necessary to keep systolic BP \> 100 mm Hg. Serum creatinine and potassium\[K+\] were measured monthly, AIC levels every 3 months and CIMT by ultrasound and endothelial function by post hyperemia and nitroglycerine (NTG) - induced peripheral artery tonometry (PAT) via finger plethysmography every six months.

Arms:
arm 1: Standard low dose inhibition of the RAS with 10 mg of benazepril orally daily to treat microalbuminuria arm 2: 40-80 mg benazepril plus 25-100 mg losartan both orally once or twice daily

Interventions: intervention 1: benazepril intervention 2: benazepril
Intervention descriptions: intervention 1: benazepril 10 mg orally once daily intervention 2: 40-80 mg benazepril plus 25-100 mg losartan orally once or twice daily

Protocol document: