OBJECTIVES: Compared to patients with an authorized discharge, patients who self-discharge AMA may be at higher risk for a future hospital readmission. Thus, the cost of discharges AMA may be alternatively examined by considering readmissions costs. The objective of this study is to estimate the relationship between discharges AMA and hospital readmissions costs in the cardiovascular disease (CVD) setting. METHODS: This cross-sectional study uses confidential inpatient hospital discharge data covering the period between January 2000 and December 2005. The outcome variables captured cost of readmissions for a CVD-related condition following an index CVD-related admission. The covariate of interest was an indicator variable for a discharge AMA in the index hospitalization. The difference in the cost of readmissions (at 7-, 31-, 180-, and 365- day intervals) following formal discharges and discharges AMA was examined using Heckman sample selection models and log linear models. The Heckman sample selection model was found to provide a better representation of the data generation process. RESULTS: The sample included 443,049 patients, of which 24,823 (5.6%) were readmitted to the same hospital. Approximately 1% of the patients who were readmitted to the hospital during the study period left AMA on the index admission while 0.87% of those who were not readmitted left AMA (p<0.001). The cost of the first readmission within 180 days was 9% (p=0.03) higher for patients discharged AMA on index admission compared to those who were discharged formally. The cost of all readmissions within 180 days and 365 days were 10% (p=0.02) and 9% (p=0.02) higher for patients discharged AMA on index admission compared to those who were discharged formally. CONCLUSIONS: A self-discharge AMA among patients admitted for CVD is associated with higher readmissions costs when readmissions occur within 6 months or 1 year.