Effect of a six-month therapy with alfacalcidol on muscle power and balance and the number of fallers and falls.

Purpose: In an open observational prospective multicentered study on a cohort of patients with a creatinine clearance of < or = 65 ml/min and diagnosed with the "Esslinger Fall Risk Assessment" to be at an increased risk for falls the effect of daily treatment with 1 microg alfacalcidol (CAS 41294-56-8; Alpha-D3) on muscle power, balance and number of fallers and falls was investigated.

Methods: In this open prospective study on 237 participants recruited in Germany, 16.9% men and 83.1% women with a mean age of 75.9 years and a mean body mass index (BMI) of 26.3 kg/m2 underwent at the beginning and after 3 and 6 months different muscle strength and balance tests such as the Timed-up and Go Test (TUG), the Tandem Stand Test (TST) and the Chair Rising Test (CRT). A successful performance in these tests has been associated with a significantly lower risk for falls and non-vertebral fractures in elderly patients (successful test performance: TUG < 12 s, TST > 10 s, CRT < 10 s).

Results: Controlled for age, gender and BMI, treatment with alfacalcidol was associated with a significantly increased performance in all three muscle and balance tests already after 3 months. This effect increased after six months of therapy and a significant increase in the number of participants who were able to successfully perform the different tests was observed: plus 74.9% for the TUG (p < .0001), plus 112% for the TST (p < .0001) and plus 108% for the CRT (p < .0001). After six months the mean time used for the TUG was decreased by 2.01 s, by 2.29 s for the CRT, and increased by 2.02 s for the TST. Controlled for age, gender, BMI and CrCI, treatment with alfacalcidol for six moths resulted in a significant 48.1% (p _< or = .0001) decrease in the absolute number of fallers and a significant 51.3% (p .0001) decrease in the absolute number of falls, compared to the 6 months prior to alfacalcidol therapy.

Conclusions: Treatment with alfacalcidol increases muscle power and balance as measured with three different muscle power and balance tests and leads to a highly significant decrease in the number of fallers and falls.