Vitamin deficiency as a risk factor for delirium

PurposeHip fracture patients constitute a frail group and are often at risk of malnutrition. These patients are also at great risk of delirium. We aimed, in a case control study, to assess the relationship between specific hypovitaminoses and the risk of delirium in hip fracture patients.SubjectsBlood was drawn for measurements of vitamins A, B1, B6, B12, C, 25(OH)D, E, and K1, as well as folic acid, in 115 patients upon admission for hip fracture. Delirium was assessed daily preoperatively and 5 days postoperatively (all patients) or until discharge (delirious patients) using the Confusion Assessment Method. Patients with delirium were classified as cases and patients without delirium as controls.ResultsA total of 59 (51%) patients had delirium during their hospital stay. Concentrations of 25(OH)D and vitamin C were significantly lower in cases compared with controls (median nmol/L 25(OH)D: 41 (32–52) vs. 52 (34–77), P = 0.05; mean μmol/L vitamin C: 25 ± 16 vs. 35 ± 20, P = 0.01). A concentration below 50 nmol/L for 25(OH)D was an independent and significant risk factor for delirium (odds ratio = 2.7; 95% confidence interval: 1.04–7.2, P = 0.04) in a multivariate regression analysis adjusted for all registered confounders.Discussion and conclusionVitamin D deficiency may increase the risk of delirium after hip fracture.