ABSTRACT ORGANIZATION OF HOSPITAL NURSING AND READMISSIONS IN SURGICAL MEDICARE PATIENTS Chenjuan Ma Matthew D. McHugh Linda H. Aiken Hospital readmissions are prevalent and costly, particularly among older adults. They have been targeted as a field for improving quality of care and reducing healthcare cost. Nursing is a critical factor in determining the quality of patient care. Despite increasing evidence linking nursing to various patient outcomes; there is an absence of research examining the nursing-readmission relationship. The purpose of this study is to identify the association between organization of hospital nursing and readmissions in surgical Medicare patients. Three organizational features of hospital nursing were studied, nurse work environment, nurse staffing, and nurse education. A secondary analysis was completed using a multi-state nurse survey, Medicare patient discharge data, and American Hospital Association annual survey, collected in 2006-2007. A sample of 220,914 Medicare patients and 23,090 nurses from 528 hospitals in four states (CA, FL, NJ, and PA) were analyzed. Survey responses from the study nurses were used to construct the hospital level measures of nurse work environment, patient-to-nurse ratio, and nurse education preparation. The outcome of interest is 30-day readmissions. Cross-tabulations examined readmissions by patient, hospital, and nursing characteristics. Multivariate logistic regressions estimated the effects of work environment, nurse staffing, and nurse education on 30-day readmissions when adjusting for patient and hospital characteristics as well as considering clustering of patients within each hospital. The overall rate of 30-day readmission was 10% in surgical patients. In bivariate analysis, being black, sicker, and previously hospitalized increased the risk for 30-day readmissions; patients discharged from larger, teaching, and urban hospitals had higher 30-day readmission rates. In multivariate analysis, one standard deviation worse of the work environment score or adding one additional patient per nurse each was significantly associated with an increase of 3% in patients' likelihood of 30-day readmission. The significant association between work environment and readmission persisted when adjusting for nurse staffing. This study suggests that readmissions are not uncommon among surgical older patients and worth more attention. This study provides the first evidence that better nurse work environment and lower patient-to-nurse ratio are significantly associated with lower risk of surgical readmissions. Improving hospital work environment and nurse staffing may reduce readmissions in surgical older patients.