Vitamin D With or Without Calcium Supplementation for Prevention of Cancer and Fractures: An Updated Meta-analysis for the U.S. Preventive Services Task Force

摘要: Data Synthesis: 19 RCTs (3 for cancer and 16 fracture outcomes) 28 observational studies (for were analyzed. Limited data from suggested that high-dose (1000 IU/d) vitamin D supplementation can reduce the risk total cancer, higher blood 25-hydroxyvitamin (25-[OH]D) concentrations might be associated with increased cancer. Mixed-effects dose– response meta-analyses showed each 10-nmol/L increase in 25-(OH)D concentration was a 6% (95% CI, 3% to 9%) reduced colorectal but no statistically significant dose–response relationships prostate breast Random-effects model meta-analysis combined calcium (pooled relative risk, 0.88 [CI, 0.78 0.99]) older adults, effects differed according study setting: institution (relative 0.71 0.57 0.89]) versus community-dwelling 0.89 0.76 1.04]). One RCT adverse outcomes supplementation, including renal urinary tract stones. Limitations: Most trial participants (aged 65 years) postmenopausal women. Observational heterogeneous limited by potential confounders. Conclusion: Combined may smaller among adults than institutionalized elderly persons. Appropriate dose dosing regimens, however, require further study. Evidence is not sufficiently robust draw conclusions regarding benefits or harms of prevention