Combination therapy with angiotensin-converting enzyme inhibitors (ACE inhibitors) and angiotensin II receptor blockers (ARB) has been stressed for its comprehensive blocking of the renin-angiotensin-aldosterone (RAAS) system, but evidence is lacking in settings like population-based follow-up studies in the real world.Design and Method:
This study compared the effectiveness of ACE inhibitors and ARB on stroke prevention in patients with hypertension and type 2 diabetes mellitus. Using Taiwan's National Health Insurance claims data, we identified 5445 subjects aged 18 years and older who had newly diagnosed hypertension in 1997-2010 and then developed type 2 diabetes during the screening period. Among them, 2161 patients took ACE inhibitors, 1703 ARBs alone, 165 both, and 1416 neither.Results:
During the follow-up period, stroke incidence rate was lowest (23.02 per 1000 person-years) in the ARB group, followed by the Neither group, the ACEI group and the Both group (24.06, 30.23, and 37.86 per 1000 person-years, respectively). Compared with patients in the Neither group, the adjusted hazard ratios (HRs) were 1.27 (95% CI 1.02–1.58) in the ACEI group, 0.95 (95% CI 0.74–1.22) in the ARB group, and 1.56 (95% CI 0.99–2.47) in the Both group. In a dosage-effect sub-analysis, greater reduction in stroke risk was observed in patients treated with high dosage ARBs (adjusted HR = 0 42, 95% CI 0 24–0 75) as compared with those in the Neither group.Conclusions:
ARBs may be considered as a first-line antihypertensive drug for patients with both hypertension and diabetes. As compared with those in the ACEI group, patients in the ARB group had a significant 25% lower stroke hazard, whereas this benefit was not seen in the Both group. Thus, the addition of ACE inhibitors to ARBs may offer no additional benefit or even neutralize it with respect to stroke prevention in patients with hypertension and diabetes.