Abstract 43: Readmission for Depression and Suicide Attempt Following Stroke and Myocardial Infarction

Abstract

Introduction: Depression after ischemic stroke (IS) and myocardial infarction (MI) is more common than in the general population and associated with morbidity and mortality. There is a lack of data on the relative risk of depression and suicide attempt (SA) comparing IS to MI, and nationally representative data is needed. Methods: The 2013 Nationwide Readmissions Database contains >14 million U.S. admissions. Using validated International Classification of Disease, 9 th Revision, Clinical Modification Codes in the primary diagnosis position, we identified index admission for IS (weighted n=434,495) and MI (weighted n=539,550) and readmission for depression and SA. To arrive at national estimates, we calculated weighted 30-, 60-, and 90-day readmission rates. We performed Cox Regression to calculate hazard ratios (HR) and 95% confidence intervals (CI) for readmission for depression and SA up to 1 year following IS vs. MI, adjusting for age, depression recorded during the index event, sex, length of stay, income quartile of patient zip code, discharge disposition, alcoholism, estimated severity of illness, and smoking. Results: Readmission rates for depression were consistently higher at 30, 60, and 90 days after IS compared to MI (0.04%, 0.09%, 0.12% vs. 0.03%, 0.05%, 0.07%). There was no significant difference in SA readmissions. The HR for readmission due to depression was 1.62 ([1.37-1.92], p=2.49x10 -8 ) comparing IS to MI in an unadjusted model and 1.49 [1.25-1.79] in a fully adjusted model. History of depression (3.70 [3.07-4.46], p=2.00x10 -16) , alcoholism (2.04 [1.34-3.09], p = 8.16x10 -4) , and smoking (1.38 [1.15-1.64], p = 3.98 x10 -4 ) were associated with increased risk of depression readmission. Age >70 years (0.46 [0.37-0.55], p = 7.66 x10 -15 ) and discharge home (0.69 [0.57-0.83], p = 1.54 x10 -3 ) were associated with reduced risk of depression readmission. Conclusion: In conclusion, IS was associated with a greater hazard of readmission for depression compared to MI but there were no differences for SA. Though both are acute ischemic vascular events, the damage to the brain may contribute to depression pathogenesis, and the greater disability from stroke may contribute to higher rates of depression.