The "weekend (WE) effect" defines the association between WE hospital admissions and higher rate of mortality. The aim of this study was to evaluate the relationship between WE effect and renal transplant recipients (RTRs) using the database of the Emilia-Romagna region (ERR), Italy. We included ERR admissions of RTRs ( International Classification of Diseases, Ninth Revision, Clinical Modification [ ICD-9-CM] code V420) between 2000 and 2013. In-hospital mortality, admissions due to cardiovascular events (CVEs), and the Elixhauser score were evaluated on the basis of ICD-9-CM codification. Out of 9063 hospital admissions related to 3648 RTRs (mean age 53 ± 13 years, 62.9% male), 1491 (16.5%) were recorded during the WE. During the follow-up period, 1581 (17.4%) patients deceased and 366 (4%) had CVEs. Length of hospital stay (LOS) was 9.7 ± 12.1 days. Logistic regression analysis showed that only LOS was independently associated with WE admissions (odds ratio: 1594, confidence interval: 1.385-1.833; P < .001). Renal transplant recipients are not exposed to higher risk of adverse outcome during WE admissions. However, WE admissions were characterized by an increased duration of hospitalization.
Keywords: Elixhauser score; ICD-9-CM; cardiovascular events; in-hospital mortality; renal transplant recipients; weekend effect.