Multimorbidity in Patients With Acute Coronary Syndrome Is Associated With Greater Mortality, Higher Readmission Rates, and Increased Length of Stay

OBJECTIVE: The aims of this systematic review were to determine the magnitude and impact of multimorbidity (≥2 chronic conditions) on mortality, length of stay, and rates of coronary intervention in patients with acute coronary syndrome (ACS) and to compare the prevalence of cardiovascular versus noncardiovascular multimorbidities. METHODS: MEDLINE, PubMed, MedlinePlus, EMBASE, OVID, and CINAHL databases were searched for studies published between 2009 and 2019. Eight original studies enrolling patients with ACS and assessing cardiovascular and noncardiovascular comorbid conditions met the inclusion criteria. Study quality was evaluated using the Crowe Critical Appraisal Tool. RESULTS: The most frequently examined cardiovascular multimorbidities included hypertension, diabetes, heart failure, atrial fibrillation, stroke/transient ischemic attack, coronary heart disease, and peripheral vascular disease; the most frequently examined noncardiovascular multimorbidities included cancer, anemia, chronic obstructive pulmonary disease, renal disease, liver disease, and depression. The prevalence of multimorbidity in the population with ACS is high (25%-95%). Patients with multimorbidities receive fewer evidence-based treatments, including coronary intervention and high-dose statins. Patients with multimorbidities experience higher in-hospital mortality (5%-13.9% vs 2.6%-6.1%), greater average length of stay (5-9 vs 3-4 days), and lower rates of revascularization (9%-14% vs 39%-42%) than nonmultimorbid patients. Women, despite being the minority in all sample populations, exhibited greater levels of multimorbidity than men. CONCLUSIONS: Multimorbid patients with ACS are at a greater risk for worse outcomes than their nonmultimorbid counterparts. Lack of consistent measurement makes interpretation of the impact of multimorbidity challenging and emphasizes the need for more research on multimorbidity's effects on postdischarge healthcare utilization.