Association between Vitamin D Deficiency and Prognosis after Hip Fracture Surgery in Older Patients in a Dedicated Orthogeriatric Care Pathway

OBJECTIVES: Vitamin D deficiency is common in patients undergoing hip fracture surgery (HFS) and has been found to be associated with poor post-operative outcome in other settings. This study aimed to analyze the association between vitamin D status and prognosis after HFS. DESIGN: Observational, prospective, single-center study. SETTING AND PARTICIPANTS: All patients admitted in a peri-operative geriatric unit between 2009 and 2020 for HFS were included. MEASUREMENTS: A moderate vitamin D deficiency was defined by a vitamin D level between 25 and 75 nmol/l and a severe deficiency by a vitamin D level <25 nmol/l. Primary endpoint was mortality 6 months after surgery. Secondary endpoints were bacterial infections and delirium during hospitalization. Odds ratio (OR) and 95% confidence interval (95%CI) were computed using logistic regression models with adjustment for confounders. RESULTS: 1197 patients were included (median age 87 years, IQR [82-91]). Median vitamin D level was 55 nmol/l (IQR [30-75 nmol/l]). Moderate and severe vitamin D deficiencies were reported in 53% and 21% of patients, respectively. There was no significant association between moderate or severe vitamin D deficiencies and 6-month mortality (OR 0.91, 95%CI [0.59-1.39], and OR 1.31, 95%CI [0.77-2.22], respectively), bacterial infection (OR 0.89, 95%CI [0.60-1.31] and OR 1.55, 95%CI [0.99-2.41], respectively), nor delirium (OR 1.03, 95%CI [0.75-1.40], and OR 1.05, 95%CI [0.70-1.57], respectively). CONCLUSION: Vitamin D deficiency was not associated with mortality, bacterial infection or delirium after HFS. Our results suggest that comorbidities, functional status and post-operative complications are the main determinants of post-operative outcome after HFS.