Survival Analysis of Hospital Stay after Acute Stroke, Puerto Rico Cardiovascular Surveillance Study

BACKGROUND: Stroke is a leading cause of death, placing a heavy burden on society at a cost of $38.6 billion annually.  Length of stay is the major determinant of cost during acute stroke hospitalization.  This study evaluated the relationship between length of stay and destination after discharge as outcomes measures of 518 stroke patients at six hospitals in four metropolitan municipalities and Mayagüez, during year 2011.

METHODS:   This secondary analysis was based on data from the Puerto Rico Cardiovascular Surveillance Study. Prolonged hospital stay was defined as hospitalization for longer than 12 days after admission.  Comparisons of proportions between groups of length of stay were based on Pearson’s Chi-square test.  Survival probabilities were determined using Kaplan-Meier curves and log-ranks test.  Multivariate Cox proportional hazards models were fitted to identify predictors of length of stay.

RESULTS:   Prolonged hospital stay was recorded in 77 (14.9%) patients.  Female gender and being discharged to a Rehabilitation Facility were significantly more frequent among patients with Prolonged hospital stay.  Male patients had a higher probability of being discharged within the first 70 days; however, patients discharged to Rehabilitation Facility showed the lowest probability.  Elderly patients showed a decreased Hazard-Ratio of discharge.  A significant difference between diagnosis groups with regard to length of stay was also observed (c² 25.6, p<0.001).  Those patients with intra-cerebral hemorrhage were least likely to have shorter length of stay.

CONCLUSIONS:   The survival distribution of length of stay in hospital was influenced by gender, age and discharge destination.  Future studies plan to identify clinical predictors for Prolonged hospital stay.