Abstract
OBJECTIVE: (1) To confirm that vitamin D deficiency, defined as serum 25-hydroxyvitamin D (25OHD) concentration < 25 nmol/L, was associated with long length-of-stay (LOS) among older inpatients admitted to geriatric acute care unit; and (2) to examine which combination of risk factors of longer LOS including vitamin D deficiency best predicted longer LOS. STUDY DESIGN AND SETTING: Based on a prospective cohort study with a 25-day follow-up on average, 531 consecutive older inpatients (mean age 85.0±7.2 years, 59.1% women) admitted to the geriatric acute care unit of Angers University Hospital, France, were included. RESULTS: Linear regression models showed that male gender (P<0.025), delirium (P<0.015) and vitamin D deficiency (P<0.001) were independently associated with a longer LOS. The highest risk of a longer LOS was shown while combining vitamin D deficiency with male gender (Odds ratio (OR)=3.70 with P< 0.001). The risk increased significantly while delirium was associated with these two baseline characteristics (OR=4.76 with P=0.001). Kaplan-Meier distributions of discharge differed significantly between participants who had or not the combination of the 3 criteria (P<0.007). CONCLUSIONS: Vitamin D deficiency, delirium and male gender were significant risk factors for a longer LOS in the studied sample of older inpatients.