Beyond ONTARGET: angiotensin-converting enzyme inhibition and angiotensin II receptor blockade in combination, a lesser evil in some?Diabetes Obes Metab 2010; 12(12):1072-8DO
Following the recent Ongoing Telmistartan Alone and in Combination With Ramipril Global Endpoint Trial (ONTARGET) finding of adverse renal outcomes, dual renin-angiotensin blockade has fallen out of favour, despite antihypertensive and antiproteinuric efficacy. However, in high-risk severe hypertension, not studied in ONTARGET, whether combination treatment should be withheld or withdrawn is not clear. We examine the renal effects of angiotensin-converting enzyme inhibitor (ACE-I) and angiotensin II receptor blocker (ARB) monotherapy versus combination therapy in patients with type 2 diabetes and varying degrees of hypertension.
Subjects attending a hospital diabetes centre were selected as case (combination therapy, n = 120) and control (monotherapy, n = 480). Subjects were matched for age, gender, ethnicity, estimated glomerular filtration rate (eGFR), blood pressure (BP) and study duration. Patients were stratified by BP, hypertension stage 1 (BP < 160/100, n = 506) and stage 2 (≥160/100, n = 94), and by treatment group. Data were analysed for the primary renal outcome of eGFR decline ≥20 ml/min, over a median of 3.7 years.
In keeping with the ONTARGET study, for stage 1 hypertension, combination treatment is significantly worse than monotherapy for the primary outcome of eGFR decline ≥20 ml/min (20 vs. 10.7%, p = 0.01). In contrast, for stage 2 hypertension, this endpoint was reached less often for combination versus monotherapy (12.0 vs. 23.2%, p = 0.2). Combination treatment was also not detrimental in patients with proteinuria or eGFR < 60 ml/min and was associated with fewer macrovascular events.
Given that hypertension control is paramount and in the spirit of primum non nocere, these data are reassuring should clinicians choose to use ACE-I and ARB combination therapy in the very hypertensive diabetic patient.