Nationwide frequency and association of heart failure on stroke outcomes in the United States

Abstract

Background: Few studies of the effect of heart failure (HF) on stroke outcomes have been published. This study was designed to determine the association of co-existing HF with in-hospital length-of-stay (LOS), cost, and mortality among acute stroke patients admitted to hospitals in the United States (US).

Methods and results: All patients with a primary diagnosis of stroke admitted to the US hospitals in calendar years 1995 and 2005 were extracted using the National Inpatient Sample (NIS) database. Patients were categorized based on a secondary diagnosis of HF. Patients' demographics, LOS, in-hospital death, disposition, and hospitalization costs were determined. The odds ratio of in-hospital mortality rates for stroke patients with HF were 2.5 (95% CI: 2.4-2.7) and 2.2 (95% CI: 2.0-2.3) in 1995 and 2005, respectively, compared to those without HF. Stroke patients with HF also stayed longer in the hospital in both years studied, though a general decline in LOS was observed in 2005. The estimated increase in total hospitalization cost for stroke patients with HF was $1,100 (20% difference, 95% CI: 18%-23%) and $1,300 (18% difference, 95% CI: 16%-20%) for 1995 and 2005, respectively.

Conclusions: The results of our study suggest that there is an association between co-existing HF and mortality in stroke patients. Stroke patients with HF appear to have a higher mortality rate, longer LOS, and higher hospitalization cost compared to those without HF. The mechanism of higher stroke mortality and morbidity in patients with HF requires further investigation to identify modifiable factors and to tailor better treatment options.