Correlation of admitted nursing home residents’ hospital length of stay and vitamin D levels

OBJECTIVE: To determine the relationship between low vitamin D levels and hospital length of stay in nursing home residents who were admitted to acute medical floors in an urban community teaching hospital. METHODS: This prospective cohort study used multiple regression analysis for patients transferred from nursing homes to the hospital. On admission, patients’ serum 25(OH)D levels were obtained by blood draw using partially purified lipid extracts via a competitive protein binding assay. We defined low levels of serum 25(OH)D as <30 ng/ml. Patient medical histories were compiled by retrospective chart review and/or patient interview. Medical histories were analyzed with special emphasis on history of falls, osteoporosis, comorbidities, medication profile, and hospital length of stay. RESULTS: The mean serum 25(OH)D level for 71 patients (N = 71) was 22.69 ng/ml (±SD 10.967); the median, 23 ng/ml. Low serum concentrations of 25(OH)D were recorded in 51 patients (72%) all of whom had a longer mean hospital length of stay (13.72 days ± SD 10.778) than the 20 patients with higher vitamin D levels (7.72 days ± SD 4.070). CONCLUSION: Low vitamin D levels in nursing home residents admitted to a community hospital were directly associated with increased hospital length of stay.