CAC score as a possible criterion for administration of angiotensin converting enzyme inhibitors and/or angiotensin receptor blockers: the MultiEthnic Study of Atherosclerosis.

INTRODUCTION: Several trials have demonstrated that angiotensin converting enzyme inhibitors (ACEIs) decrease cardiovascular (CV) mortality rates in patients with heart failure; however, the Prevention of Events with Angiotensin-Converting Enzyme Inhibition (PEACE) and European Trial on Reduction of Cardiac Events with Perindopril in Stable Coronary Artery Disease (EUROPA) trials failed to show significant similar preventive effects in normal ejection fraction patients. We evaluated the baseline coronary artery calcium (CAC) score as a predictor of the effects of ACEIs/angiotensin receptor blockers (ARBs) on outcomes among normal ejection fraction participants.

METHODOLOGY: Of 6814 MultiEthnic Study for Atherosclerosis population participants (after exclusion of the patients temporarily using ACEIs and/or ARBs during follow-up), we evaluated 2906 participants who never used ACEIs/ARBs and 368 (8.7%) participants who constantly used them during all baseline and follow-up examinations. In the population studied, 53.9% were men, aged 60.8±10.0 years, who had no apparent clinical CV disease. We compared CV event rates and multivariable-adjusted hazard ratios after stratifying by ACEI/ARB use and stratifying CAC scores by category (0, 1-399, and ≥400).

RESULTS: The event rates varied from 1.8 to 41.2/1000 person years among the CAC groups. Among the participants with a 1-399 CAC score, ACEI/ARB users had significantly lower event rates than nonusers (4.9 vs. 8.2, respectively). Hazard ratio in the adjusted model was 3.1 (95% confidence interval 1.14-8.78, P<0.05). There was no significant event rate difference between ACEI/ARB users and nonusers among other CAC groups.

CONCLUSION: The use of ACEIs/ARBs was associated with significantly fewer CV events in asymptomatic participants with low to intermediate CAC scores. Thus, better risk stratification in asymptomatic individuals (such as using CAC scores) may assist in proper selection of patients for further CV risk reduction strategies.