Effect of calcium and vitamin D supplementation on bone mineral density in women aged 65–71 years: a 3-year randomized population-based trial (OSTPRE-FPS)
The Osteoporosis Risk Factor and Prevention-Fracture Prevention Study (OSTPRE-FPS) was a randomized population-based open trial (n = 593). The supplementation group (n = 287) received daily cholecalciferol 800 IU + calcium 1,000 mg for 3 years while the control group (n = 306) received neither supplementation nor placebo. Daily vitamin D and calcium supplementation have a positive effect on the skeleton in ambulatory postmenopausal women. Vitamin D deficiency is common in the elderly, and vitamin D levels are associated with low bone mineral density (BMD). The working hypothesis was that vitamin D and calcium supplementation could prevent bone loss in ambulatory postmenopausal women. The OSTPRE-FPS was a randomized population-based open trial with a 3-year follow-up in 3,432 women (aged 66 to 71 years). A randomly selected subsample of 593 subjects underwent BMD measurements. The supplementation group (n = 287) received daily cholecalciferol 800 IU + calcium 1,000 mg for 3 years while the control group (n = 306) received neither supplementation nor placebo. In the intention-to-treat analysis, total body BMD (n = 362) increased significantly more in the intervention group than in the control group (0.84% vs. 0.19%, p = 0.011). The BMD change differences at the lumbar spine (p = 0.372), femoral neck (p = 0.188), trochanter (p = 0.085), and total proximal femur (p = 0.070) were statistically nonsignificant. Analyses in compliant women (≥80% of use) resulted in stronger and statistically significant effects at the total body and femoral regions. Daily vitamin D and calcium supplementation have a positive effect on the skeleton in ambulatory postmenopausal women with adequate nutritional calcium intake.