Effects of Bisphosphonates and Calcium plus Vitamin-D Supplements on Cognitive Function in Postmenopausal Osteoporosis§

Background: Postmenopausal osteoporosis has been linked to accelerated cognitive decline; however, little is known about the effects of medical treatment on cognitive functions. Material and Methods: In this prospective study, we evaluated the effects of bisphosphonate treatment and calcium plus vitamin D supplementation on cognitive functions in 45 women with postmenopausal osteoporosis who were started on medical treatment. The medications included alendronate, zoledronic acid, risedronate, or ibandronic acid along with a low or high dose of calcium plus vitamin D supplements. The cognitive function was assessed by the mini-mental state examination (MMSE) test. All subjects underwent bone mineral density (BMD) measurement via dual-energy X-ray absorptiometry at baseline and at study completion. Results: The mean T-score improved significantly at 1 year, except for neck of the femur area. The mean MMSE score did not change significantly at 12 months (26.40 ± 2.07 vs. 26.48 ± 2.07; p = 0.513), with no difference among bisphosphonates combined with calcium plus vitamin D. Higher dose (1200 mg/800 U/day) of calcium plus vitamin D supplementation tended to have a greater improvement as compared with lower dose (600 mg/400 U/day) (Δ MMSE: 0.11 ± 0.72 vs. −0.14 ± 0.69). Conclusions: Cognitive functions in the women remained unaltered, whereas bone BMD T-scores were significantly improved at the 12th month after the administration of bisphosphonates and calcium plus vitamin D supplements. Higher doses of calcium plus vitamin D supplements were likely to have better cognitive effects as compared with lower doses.