Abstract Body (Do not enter title and authors here): Background
A Type 2 (T2) myocardial infarction (MI) occurs “secondary to ischemia due to either increased oxygen demand or decreased supply,” while a Type 1 MI (T1) is atherothrombotic. Treatment includes correction of the underlying cause and not catheterization. The current study's aim is to assess the patient-centered outcome of days not at home (DNAH) within a year of discharge among older adults hospitalized with T1 and T2 MI, and to evaluate the distribution of non-home days.

Methods
Data for this analysis came from a prospective cohort study of adults ≥75 years old hospitalized with MI at 94 U.S. hospitals and linked to Medicare claims and encounter data. MI type was adjudicated according to the Fourth Universal Definition of MI. Patient characteristics were identified via chart review or self-report. DNAH was defined as the number of days dead or in a hospital, skilled nursing facility (SNF), rehab facility, or hospice. Multivariable-adjusted negative binomial regression was used to evaluate the association between MI type and DNAH in the year after discharge.

Results
Of the 375 participants evaluated in this interim analysis, 264 (70.4%) had T1 MI and 111 (29.6%) had T2 MI. There was no difference in distribution of age, gender, or race. T2 patients were more likely to have heart failure (HF), coronary artery disease (CAD), COPD, and arrythmias. Patients with T2 MI had a median [interquartile range] of 5 [0-71] DNAH in the year after discharge, compared with 2 [0-10] DNAH among patients with T1 MI (p = 0.008). After adjusting for age and comorbidities, T2 patients had 137% more DNAH (IRR = 2.37, 95% CI = 1.43, 3.94, p < 0.001) than T1 patients. The number of days dead or in SNF was significantly higher among patients with T2 MI compared with T1 MI, whereas the association between MI type and increase in days readmitted was borderline (p = 0.06). In the multivariable model, age, HF, and CAD were significantly associated with more DNAH, but COPD and arrhythmias were not.

Conclusion
Our findings demonstrate that older patients with T2 MI have more days not at home, attributable to death, SNF stays, and to a lesser extent, rehospitalization. Interestingly, accounting for comorbidities did not significantly attenuate this association. Further studies are needed to develop guidelines for medical teams, including evaluating how receipt of cardiac interventions impacts home days in older patients with T1 and T2 MI.