Thirty-Day Rehospitalizations After Acute Myocardial Infarction: A Cohort Study

Study Questions:

What are the frequency and predictors of rehospitalization within 30 days of myocardial infarction (MI)?

Methods:

The authors assessed the incidence and complications during the initial and subsequent hospitalization of 3,010 patients who were hospitalized in Olmsted County with first-ever MI from 1987 to 2010, and survived to hospital discharge. Manual chart review was performed to determine the cause of all rehospitalizations.

Results:

The mean age of the 3,010 patients was 67 years, and 40% were females. The initial diagnosis was ST-segment elevation MI in 31% of the patients. There were 643 rehospitalizations within 30 days in 561 (18.6%) patients. Overall, 30.2% of rehospitalizations were unrelated to the incident IM, 42.6% were related, and the relationship was unclear in the rest. Angiography was performed in 153 (23.8%) rehospitalizations, and revascularization was performed in 103 (16.0%) rehospitalizations, of which 46 (44.7%) had no revascularization during the index hospitalization. After adjustment for potential confounders, diabetes, chronic obstructive pulmonary disease, anemia, higher Killip class, longer length of stay during the index hospitalization, and a complication of angiography or reperfusion or revascularization were associated with increased rehospitalization risk. The 30-day incidence of rehospitalization was 35% in patients who experienced a complication of angiography during the index MI hospitalization, and 31% in those who experienced a complication of reperfusion or revascularization during the index MI hospitalization, compared with 17% in patients who had reperfusion or revascularization without complications.

Conclusions:

Rehospitalization after MI is related to comorbid conditions, longer length of stay, and complications of angiography and revascularization or reperfusion. Most rehospitalizations were unrelated to the incident MI.

Perspective:

Rehospitalization after MI is common, varies across hospitals, and has recently been designated a quality measure. This study provides a thorough assessment of rehospitalization after MI, and should help guide both care and policy. Since comorbid conditions are the best predictors of readmission, comprehensive discharge planning for these patients should be explored to help reduce the risk of rehospitalization. Most admissions after an MI were not related to the MI, and this finding should temper efforts to link lower readmissions to financial incentives for hospitals.

Keywords: Hospitals, Pulmonary Disease, Chronic Obstructive, Myocardial Infarction, Patient Readmission, Cardiology, Cardiovascular Diseases, Patient Discharge, Hospitalization, Diabetes Mellitus, Length of Stay


< Back to Listings