The Prevalence and Impact of Evidence-Based Medications on Cardiovascular and Cerebrovascular Outcomes in Patients with Acute Coronary Syndrome Post-Revascularization in Oman

Objectives: International cardiovascular guidelines recommend prescribing a combination of five evidence-based medications (EBM) for acute coronary syndrome (ACS) patients post-revascularization. This study aims to assess the prevalence and impact of prescribing the full (five medications) versus partial (four medications or fewer) EBM combination on major adverse cardiovascular and cerebrovascular events (MACCE) in patients with ACS post-revascularization. Methods: Data from patients with ACS who had revascularization between January 2016 and September 2021 were collected retrospectively. Patients were then followed up until March 2022 for MACCE. Results: The full EBM combination was prescribed to 70% of the patients. However, after taking into account the presence of contraindications and clinical factors, the actual adherence to the guidelines was 95%. Patients who received the full EBM combination were younger (58 versus 62 years; p = 0.0 and 3) and had lower rates of chronic kidney disease (11% versus 41%; p < 0.001) and heart failure (9% versus 20%; p = 0.012) when compared to patients who received the partial EBM. Compared to the partial EBM group, the full EBM group was associated with lower MACCE rates (54% versus 37%, p = 0.012). After employing the propensity score technique utilizing the 1:1 nearest neighbor matching method without replacement, the univariate findings were further re-affirmed with those on full EBMs (compared to those on partial EBMs) associated with a significant reduction in the MACCE rate (average treatment effect of −25%; 95% confidence interval: −10–−40%; p = 0.001). Conclusions: The full EBM utilization was significantly high in our setting and in line with international guidelines. The full EBM combination was predominantly prescribed in younger and less comorbid patients and was associated with lower MACCE rates. The findings were further reaffirmed by the propensity score matching method.