VITamin D and OmegA-3 TriaL (VITAL): Fractures, Vitamin D and Genetic Markers

The VITamin D and OmegA-3 TriaL (VITAL; NCT 01169259) is a randomized clinical trial in 25,871 U.S. men and women investigating whether taking daily dietary supplements of vitamin D3 (2000 IU) or omega-3 fatty acids (Omacor® fish oil, 1 gram) reduces the risk of developing cancer, heart disease, and stroke in people who do not have a prior history of these illnesses. This ancillary study is being conducted among participants in VITAL and will examine (1) whether vitamin D reduces incident total, non-vertebral fractures, and hip fractures and (2) whether this reduction is modified by vitamin D levels

The VITAL: Vitamin D, Fractures, and Genetic Markers is an ancillary study of the parent VITAL trial (VITamin D and OmegA-3 TriaL). The study will require the adjudication of all self-reported incident fracture events among 25,871 men and women. Findings from this ancillary study will inform clinical practice on the role(s) of vitamin D supplements in fracture prevention. This proposal will generate important positive or informative negative results about effects of supplemental vitamin D3 alone on fracture risk, while also elucidating the relative importance of vitamin D biomarkers and genetic variations in vitamin D-related pathways on bone. Findings from the proposed ancillary study have the potential for major clinical as well as public health impact for both men and women in the U.S.

Omacor, 1 capsule per day. Each capsule of Omacor contains 840 milligrams of marine omega-3 fatty acids (465 mg of eicosapentaenoic acid [EPA] and 375 mg of docosahexaenoic acid [DHA]).

To determine whether vitamin D supplementation will reduce incident total, non-vertebral, and hip fractures according to annual questionnaires, medical record review, and fracture adjudication.

To determine whether baseline vitamin D levels and genetic variation in vitamin D-related pathways modify effects of vitamin D supplements on fractures.

LeBoff MS, Yue AY, Copeland T, Cook NR, Buring JE, Manson JE. VITAL-Bone Health: rationale and design of two ancillary studies evaluating the effects of vitamin D and/or omega-3 fatty acid supplements on incident fractures and bone health outcomes in the VITamin D and OmegA-3 TriaL (VITAL). Contemp Clin Trials. 2015 Mar;41:259-68. doi: 10.1016/j.cct.2015.01.007. Epub 2015 Jan 24.

LeBoff MS, Chou SH, Murata EM, Donlon CM, Cook NR, Mora S, Lee IM, Kotler G, Bubes V, Buring JE, Manson JE. Effects of Supplemental Vitamin D on Bone Health Outcomes in Women and Men in the VITamin D and OmegA-3 TriaL (VITAL). J Bone Miner Res. 2020 May;35(5):883-893. doi: 10.1002/jbmr.3958. Epub 2020 Jan 30.

LeBoff MS, Chou SH, Ratliff KA, Cook NR, Khurana B, Kim E, Cawthon PM, Bauer DC, Black D, Gallagher JC, Lee IM, Buring JE, Manson JE. Supplemental Vitamin D and Incident Fractures in Midlife and Older Adults. N Engl J Med. 2022 Jul 28;387(4):299-309. doi: 10.1056/NEJMoa2202106.

Chou SH, Murata EM, Yu C, Danik J, Kotler G, Cook NR, Bubes V, Mora S, Chandler PD, Tobias DK, Copeland T, Buring JE, Manson JE, LeBoff MS. Effects of Vitamin D3 Supplementation on Body Composition in the VITamin D and OmegA-3 TriaL (VITAL). J Clin Endocrinol Metab. 2021 Apr 23;106(5):1377-1388. doi: 10.1210/clinem/dgaa981.

LeBoff MS, Murata EM, Cook NR, Cawthon P, Chou SH, Kotler G, Bubes V, Buring JE, Manson JE. VITamin D and OmegA-3 TriaL (VITAL): Effects of Vitamin D Supplements on Risk of Falls in the US Population. J Clin Endocrinol Metab. 2020 Sep 1;105(9):2929-38. doi: 10.1210/clinem/dgaa311.