Vitamin D Supplementation Improves Muscle Mass, Physical Function, and Quality of Life in Patients With Degenerative Lumbar Disease

Degenerative lumbar disease is a significant contributor to acute or chronic musculoskeletal issues in the elderly, often associated with low serum 25-hydroxyvitamin D (25(OH)D) levels. The effect of vitamin D₂ supplementation on muscle mass, strength, and physical performance remains unclear. This study aimed to determine the effect of vitamin D₂ supplementation on these parameters in patients with degenerative lumbar disease and low vitamin D status. A total of 115 patients with serum 25(OH)D levels < 30 ng/mL were administered 40,000 IU of vitamin D₂ (ergocalciferol) weekly for 6 months. Body composition, serum 25(OH)D, parathyroid hormone (PTH) levels, muscle strength, and physical performance were examined before and after 6 months of vitamin D₂ supplementation. Baseline median serum 25(OH)D was 24.9 ng/mL; 79.1% had vitamin D insufficiency, and 20.9% had vitamin D deficiency. After supplementation, median 25(OH)D increased to 43.1 ng/mL (p < 0.001), with a significant reduction in PTH (p < 0.001). Significant improvements were observed in muscle mass (p = 0.04), balance test (p = 0.01), gait speed (p = 0.009), chair stand test (p < 0.001), short physical performance (p < 0.001), Oswestry disability index (p < 0.001), and visual analog scale (VAS) scores (p < 0.001). Post-supplementation 25(OH)D levels correlated negatively with body mass index (ρ = -0.187, p = 0.045), fat mass (ρ = -0.219, p = 0.019), fat percentage (ρ = -0.199, p = 0.033), and VAS score (ρ = -0.313, p < 0.001). Six months of vitamin D₂ supplementation significantly improved vitamin D status, muscle mass, physical performance, and quality of life in patients with degenerative lumbar disease.