Relationship between length of hospitalary stay and early readmission

BACKGROUND: TO analyze the relationship between lenght of hospitalary stay and early readmission rate. To assess the hypothesis that those admissions with the lowest lenght of stay are associated with higher early readmission rate. PATIENTS AND METHODS: Retrospective study of 35,902 hospital admissions. A single admission was selected randomly for each patient. The readmission risk during 31 days were related with length of stay level. Logistic regression model was applied to adjusting by other variables (age, sex, admission year, emergency admission, patient residence, payer). RESULTS: The early readmission rate is lower in the admissions with low outlier lenght of stay than with not outlier lenght of stay (5.8% vs 9.8%). After adjusting for other variables the odds ratio is under 1 but not statically significant (0.90; 0.80-1.02). Admissions with high lenght of stay outlier haver higher early readmission rate (10.4%), with adjusted odds ratio of 1.14 (1.02-1.27). CONCLUSIONS: Admissions with lowest lenght of stay did not have a high early readmission risk.