Passive Prescription of Secondary Prevention Medical Therapy during Index Hospitalization for Acute Myocardial Infarction Is Prevalent and Associated with Adverse Clinical Outcomes

Abstract

Secondary prevention therapy reduces death and reinfarction after acute myocardial infarction (AMI), but it is underutilized in clinical practice. Mechanisms for this therapeutic gap are not well established. In this study, we have explored and evaluated the impact of passive continuation compared to active initiation of secondary prevention therapy for AMI during the index hospitalization. For this purpose, we have analyzed 1083 consecutive patients with AMI to a tertiary referral hospital in Hong Kong and assessed discharge prescription rates of secondary prevention therapies (aspirin, beta-blockers, statins, and ACEI/ARBs). Multivariate analysis was used to identify independent predictors of discharge medication, and Kaplan–Meier survival curve was used to evaluate 12-month survival. Overall, prescription rates of aspirin, beta-blocker, statin, and ACEI/ARBs on discharge were 94.8%, 64.5%, 83.5%, and 61.4%, respectively. Multivariate analysis showed that prior use of each therapy was an independent predictor of prescription of the same therapy on discharge: aspirin (odds ratio (OR) = 4.8, 95% CI = 1.9–12.3, $P<0.01$ ), beta-blocker (OR = 2.5, 95% CI = 1.8–3.4, $P<0.01$ ); statin (OR = 8.3, 95% CI = 0.4–15.7, $P<0.01$ ), and ACEI/ARBs (OR = 2.9, 95% CI = 2.0–4.3, $P<0.01$ ). Passive continuation of prior medication was associated with higher 1-year mortality rates than active initiation in treatment-naïve patients (aspirin (13.7% vs. 5.7%), beta-blockers (12.9% vs. 5.6%), and statins (11.0% vs. 4.6%); all $P<0.01$ ). Overall, the use of secondary prevention medication for AMI was suboptimal. Our findings suggested that the practice of passive continuation of prior medication was prevalent and associated with adverse clinical outcomes compared to active initiation of secondary preventive therapies for acute myocardial infarction during the index hospitalization.