Abstract 107: Home Health Care After Discharge is Associated With Less Early Readmissions for Patients With Acute Myocardial Infarction

Abstract

Objective: Home health care (HHC) is a support tool to transition patients after discharge and acute myocardial infarction (AMI) is a significant cause of morbidity and mortality in the U.S. However, little is known regarding the impact of HHC on AMI patients. We sought to identify predictors of readmissions among AMI patients, characteristics of those who receive HHC and investigate the association of HHC with readmission. Methods: We queried the National Readmission Database (NRD) (January 2012 - December 2014), to identify patients discharged after AMI and selected patients who were discharged home with (HHC+) and without HHC (HHC-). We reported national estimates with survey methods with weights provided in our data. After univariate exploratory analyses, we developed a regression model to identify the probability of each patient to receive HHC. From the propensity score, we calculated average treatment on the treated (ATT) weights. These ATT weights were included in the logistic regression model to determine the impact of HHC on readmission after adjusting for available clinical confounders. We considered post-weighting standardized differences <10% as appropriate for our ATT model. To determine clinical factors associated with readmission, we also performed a multi-variable logistic regression with readmission as the end-point. All results were reported as risk ratios (RR) with their 95% confidence intervals (CI). Results: Between January 2012 to December 2014, 406,237 patients were treated for AMI and discharged home with or without HHC. Among these 9.4% (38,215) received HHC. HHC+ patients were older (mean age 77 ± 11 vs 60 ±12 years p<0.001), more likely to be female (53.6% vs. 26.9%, p <0.001), and have cancer (3.7% vs 1.3%, p <0.001), congestive heart failure (5.7% vs. 0.5%, p <0.001), chronic pulmonary disease (23.2% vs. 12.7%, p <0.001), chronic kidney disease (26.9% vs 6.9%, p <0.001), diabetes (35.6% vs. 26.7%, p <0.001), hypertension (70.7% vs. 64.8%, p <0.001) and peripheral vascular disease (14.6% vs 6.4%, p <0.001). Patients readmitted after MI were more likely to be older and have diabetes (RR 1.42, 95% CI 1.37-1.48), CHF (RR 5.89, CI 5.55-6.26) or COPD (RR 1.59, 1.52-1.65). Unadjusted 30-day readmission rate was 20.9% for HHC+ and 8.2% for HHC- patients. Propensity-weighted adjustment for covariates yielded 36,979 HHC+ patients and 37,785 HHC- patients. Adjusted risk rations (RR) for 30-day readmission were computed using ATT weights, and HHC+ patients had significantly lower readmission risk (RR 0.89, 95% CI 0.82 - 0.96) compared to HHC- (RR 1.12, 95% CI 1.04 - 1.21; p < 0.001) Conclusion: In the United States, a small proportion of patients receive home health care after discharge post-AMI. Older, females and those with diabetes or heart failure are more likely to receive home health care. Use of home health care may be associated with lower 30-day readmission rates after AMI.