Effectiveness of Calcifediol in Improving Muscle Function in Post-Menopausal Women: A Prospective Cohort Study

Introduction: The role of vitamin D supplementation on muscle function and physical performance is still debated. Calcifediol is an available treatment for hypovitaminosis D, particularly for extra-skeletal effects. Aim of this prospective cohort study was to evaluate the effectiveness of calcifediol on serum levels of 25(OH)D₃, appendicular muscle strength, physical performance, and prevention of falls in post-menopausal women. Methods: We recruited post-menopausal women aged ≥50 years, referring to an outpatient service for the management of osteoporosis over a 18-month period. We included women with a diagnosis of osteoporosis and/or vitamin D deficiency [serum levels of 25(OH)D₃ <30 ng/ml]. All the participants received calcifediol (20 μg, 4 oral drops/day) for a 6-month period. We evaluated at the baseline and after 6 months the following outcomes: serum levels of 25(OH)D₃, appendicular muscle strength, using the Isometric Hand Grip Strength Test and the Knee Isometric Extension Strength Test, physical performance, using the Short Physical Performance Battery (SPPB) and the 4-m gait speed (4MGS), and the risk of falls (percentage of fallers and recurrent fallers and mean number of falls). A sub-analysis was performed in patients with vitamin D deficiency. Results: We enrolled 113 post-menopausal women, mean aged 68.01 ± 9.13 years. After 6 months of treatment, there was a significant increase in serum levels of 25(OH)D₃ (p < 0.001), appendicular muscle strength (p < 0.001), and physical performance (p = 0.002 at SPPB and p = 0.010 at 4MGS, respectively). At 6 months, the percentage of fallers was lower, although not significantly (p = 0.078), whereas there was a significant reduction both in percentage of recurrent fallers and in the mean number of falls (p < 0.001 and p = 0.020, respectively). Conclusion: Calcifediol was significantly effective in improving serum levels of 25(OH)D₃ and muscle function and in reducing the percentage of recurrent fallers and the mean number of falls in a cohort of post-menopausal women.