An Age-Related Decrease in Creatinine Clearance Is Associated with an Increase in Number of Falls in Untreated Women But Not in Women Receiving Calcitriol Treatment

Decreased calcitriol production due to impaired renal function may be a significant risk factor for falls in normal aging population.The objective of the study was to examine the association between creatinine clearance (CrCl) and the incidence of falls and fallers in groups treated with placebo, calcitriol, estrogen therapy (ET)/estrogen + progestin therapy (HT), and calcitriol + ET/HT.This was a 3-yr, double-blind, placebo-controlled study designed to test the efficacy of calcitriol and ET/HT on bone loss and falls with analysis by intention to treat and post hoc.The study was conducted at an academic outpatient center.Four hundred eighty-nine normal elderly women aged 65-77 yr; 415 women completed the study.Subjects were randomized to placebo, calcitriol 0.25 mug twice a day, ET daily (conjugated equine estrogens 0.625 mg), HT (conjugated equine estrogen 0.625 mg + medroxyprogesterone acetate 2.5 mg) and calcitriol + ET/HT.Cumulative number of falls and fallers were compared between groups with 24-h urine CrCl less than 60 and 60 ml/min or greater.Calcitriol treatment decreased the number of fallers and falls. Low CrCl less than 60 ml/min was a predictor of the number of falls per person but not fallers in the placebo group (P = 0.007). In the low CrCl group (60 ml/min), the rate of falls decreased on calcitriol by 53% [95% confidence interval (CI) -71% to -22%; P = 0.003], calcitriol + ET/HT by 61% (95% CI -76% to -37%; P = 0.001), and ET/HT by 25% (95% CI: -55% to +24%; not significant). Calcitriol reduced the rate of falls by 30% (95% CI -49% to -4%; P = 0.027) in the CrCl 60 ml/min or greater group.Calcitriol treatment decreases falls in all subjects but especially in elderly women with decreased renal function (60 ml/min) and frequent fallers.