In-Hospital Management and Outcomes of Patients With Acute Myocardial Infarction and Influenza

Patients with influenza infection are at increased risk of acute myocardial infarction (AMI). There are limited data on the short-term prognosis and management of patients with AMI and concomitant influenza. We examined the National Inpatient Sample from 2010 to 2014 for adult patients with a diagnosis of AMI. Patients were stratified into those with or without concomitant influenza. In-hospital therapies and outcomes were compared between groups in unadjusted and adjusted analyses. Standardized differences of >10% and p values <0.05 were considered significant. Propensity matching was performed using a caliper radius of 0.01*sigma. Of 4,285,641 patients with a discharge diagnosis of AMI, 12,830 had concomitant influenza. Patients with influenza were older, had a higher burden of co-morbidities, and more often presented with non-ST elevation AMI (90% vs 74%) as compared with those without influenza. Coronary angiography (23% vs 54%) and revascularization (11% vs 41%) were less often pursued in AMI patients with influenza. Patients with AMI and influenza had elevated in-hospital mortality (14%) and multiorgan failure (33%). In a propensity-matched analysis of 23,415 patients, in-hospital mortality (odds ratio [OR] 1.26; p = 0.01), acute kidney injury (OR 1.36; p <0.01), multiorgan failure (OR 1.81; p <0.01), length-of-stay, and hospital costs were significantly higher in those with influenza. In conclusion, patients with AMI and concomitant influenza have an adverse in-hospital prognosis as compared with those without influenza.