Vitamin D and Postoperative Recovery in Elderly Ribeirinhos-Riverside Amazon Communities with Femur Fractures.

Background/Objectives: Vitamin D deficiency is prevalent in elderly populations and may impact surgical recovery. Despite the equatorial location, vitamin D insufficiency affects many elderly Ribeirinhos in the Brazilian Amazon. This study investigated whether pre-existing vitamin D supplementation influences postoperative outcomes in elderly Ribeirinhos following femur fracture surgery, while examining metabolic parameters and documenting chronic disease prevalence. Methods: This prospective cohort study enrolled 60 elderly Ribeirinhos patients (≥65 years) admitted for femur fracture surgery at the Regional Hospital of Lower Amazon. Twenty-two patients had participated in a vitamin D supplementation program (50,000 IU monthly, 3-6 months) prior to admission; 38 had not. Primary outcomes were hospitalization duration and serum 25-hydroxyvitamin D levels. Secondary outcomes included ionized calcium, blood glucose, and comorbidity documentation. Results: The supplementation group was associated with significantly shorter hospitalization (14.32 ± 0.79 vs. 22.61 ± 0.88 days, p < 0.0001), representing 37% reduction. Vitamin D levels were markedly higher in supplemented patients (50.26 ± 2.55 vs. 21.74 ± 0.84 ng/mL, p < 0.0001). Ionized calcium was elevated in the supplementation group (1.29 ± 0.01 vs. 1.08 ± 0.02 mmol/L, p < 0.001) without hypercalcemia. Blood glucose was lower in supplemented patients (83.8 ± 1.4 vs. 152.2 ± 9.6 mg/dL, p < 0.001). Medical records revealed that 73.3% had hypertension and 31.7% had diabetes, with 25% having both conditions. Conclusions: Pre-existing vitamin D supplementation was associated with reduced hospitalization duration following femur fracture surgery, though causality cannot be inferred due to observational design. Community-based vitamin D programs may warrant further investigation in vulnerable populations, with randomized trials needed.