Importance: The increased social and economic burdens for osteoporosis-related fractures worldwide make the prevention of such injuries a major public health goal. Previous studies have reached mixed conclusions regarding the association between calcium, vitamin D, or combined calcium and vitamin D supplements and fracture incidence in older adults.
Objective: To investigate whether calcium, vitamin D, or combined calcium and vitamin D supplements are associated with a lower fracture incidence in community-dwelling older adults.
Data Sources: The PubMed, Cochrane library, and EMBASE databases were systematically searched from the inception dates to December 24, 2016, using the keywords calcium, vitamin D, and fracture to identify systematic reviews or meta-analyses. The primary randomized clinical trials included in systematic reviews or meta-analyses were identified, and an additional search for recently published randomized trials was performed from July 16, 2012, to July 16, 2017.
Study Selection: Randomized clinical trials comparing calcium, vitamin D, or combined calcium and vitamin D supplements with a placebo or no treatment for fracture incidence in community-dwelling adults older than 50 years.
Data Extraction and Synthesis: Two independent reviewers performed the data extraction and assessed study quality. A meta-analysis was performed to calculate risk ratios (RRs), absolute risk differences (ARDs), and 95% CIs using random-effects models.
Main Outcomes and Measures: Hip fracture was defined as the primary outcome. Secondary outcomes were nonvertebral fracture, vertebral fracture, and total fracture.
Results: A total of 33 randomized trials involving 51?145 participants fulfilled the inclusion criteria. There was no significant association of calcium or vitamin D with risk of hip fracture compared with placebo or no treatment (calcium: RR, 1.53 [95% CI, 0.97 to 2.42]; ARD, 0.01 [95% CI, 0.00 to 0.01]; vitamin D: RR, 1.21 [95% CI, 0.99 to 1.47]; ARD, 0.00 [95% CI, -0.00 to 0.01]. There was no significant association of combined calcium and vitamin D with hip fracture compared with placebo or no treatment (RR, 1.09 [95% CI, 0.85 to 1.39]; ARD, 0.00 [95% CI, -0.00 to 0.00]). No significant associations were found between calcium, vitamin D, or combined calcium and vitamin D supplements and the incidence of nonvertebral, vertebral, or total fractures. Subgroup analyses showed that these results were generally consistent regardless of the calcium or vitamin D dose, sex, fracture history, dietary calcium intake, and baseline serum 25-hydroxyvitamin D concentration.
Conclusions and Relevance: In this meta-analysis of randomized clinical trials, the use of supplements that included calcium, vitamin D, or both compared with placebo or no treatment was not associated with a lower risk of fractures among community-dwelling older adults. These findings do not support the routine use of these supplements in community-dwelling older people.
Prophylactic calcium and Vitamin D are frequently taken by healthy older adults without osteoporosis to prevent fracture. Often, my patients will self-initiate these vitamins. While there is no clear association between calcium supplements and the risk of heart attack or stroke (harm), this meta-analysis demonstrates there is no clear association with fracture reduction (benefit) either. As physicians, we now have data to further reduce our patients` pill burden and save money by skipping calcium and Vitamin D.
As a general internist, I found this meta-analysis of 51,145 patients both well done and convincing. It demonstrated that neither calcium, vitamin D, nor calcium plus vitamin D prevented hip vertebral and non-vertebral fractures in community-dwelling adults.
Hopefully, this comprehensive review can help convince practitioners to prescribe less Ca/VitD in low-risk patients.
Extremely dense manuscript with tables most of which would be better placed in a supplement.
This is the second recent major meta-analysis to conclude that Ca and vis D supplementation appear not to prevent osteoporotic fractures. This appears to have been a well-constructed meta-analysis, but the conclusion has to be qualified by the fact that the average age of participants was > 70. Without reviewing each RCT, it remains unknown what percentage of the participants already had osteoporosis or what their mean BMD was, but the older age of the participants would suggest that the prevalence of low BMD was high. Despite generally longer trial lengths (~ 4 y), Ca and/or vit D may be too little, too late to have a clinically meaningful impact when administered when BMD has reached a critically low level. To me, the more important question is whether these treatments, individually or in combination, can mitigate bone loss and thus prevent osteoporotic fractures when started at or before menopause.