Serum 25-hydroxyvitamin D in the VITamin D and OmegA-3 TriaL (VITAL): Clinical and demographic characteristics associated with baseline and change with randomized vitamin D treatment
Abstract
Background: The VITamin D and OmegA-3 TriaL (VITAL) is a completed randomized, placebo-controlled trial of vitamin D3 (2000 IU/day) and marine omega-3 (1 g/day) supplements in the primary prevention of cancer and cardiovascular disease. Here we examine baseline and change in 25-hydroxyvitamin D (25(OH)D) and related biomarkers with randomized treatment and by clinical factors. Methods: Baseline 25(OH)D was measured in 15,804 participants (mean age 68 yrs; 50.8% women; 15.7% African Americans) and in 1,660 1-year follow-up samples using liquid chromatography-tandem mass spectrometry and chemiluminescence. Calcium and parathyroid hormone (iPTH) were measured by chemiluminescence and spectrophotometry respectively. Results: Mean baseline total 25(OH)D (ng/mL±SD) was 30.8±10.0 ng/mL, and correlated inversely with iPTH (r=−0.28), p<0.001. After adjusting for clinical factors, 25(OH)D (ng/mL±SE) was lower in men vs women (29.7±0.30 vs 31.4±0.30, p<0.0001) and in African Americans vs whites (27.9±0.29 vs 32.5±0.22, p<0.0001). It was also lower with increasing BMI, smoking, and latitude, and varied by season. Mean 1-year 25(OH)D increased by 11.9 ng/mL in the active group and decreased by 0.7 ng/mL in placebo. The largest increases were noted among individuals with low baseline and African Americans. Results were similar for chemiluminescent immunoassay. Mean calcium was unchanged, and iPTH decreased with treatment. Conclusion: In VITAL, baseline 25(OH)D varied by clinical…
How strong is the evidence?
Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 2 of 5 (High · randomized trial). Randomized trials of a reasonable size are the strongest single-study design. Reported size: 15,804 participants or records.
Read the paper
Related studies
- eggNOG 5.0: a hierarchical, functionally and phylogenetically annotated orthology resource based on 5090 organisms and 2502 viruses
- Online Survival Analysis Software to Assess the Prognostic Value of Biomarkers Using Transcriptomic Data in Non-Small-Cell Lung Cancer
- OptiType: precision HLA typing from next-generation sequencing data
- Nicotinic Cholinergic System and COVID-19: In Silico Identification of an Interaction between SARS-CoV-2 and Nicotinic Receptors with Potential Therapeutic Targeting Implications
- Saccharomyces cerevisiae cells have three Omega class glutathione S-transferases acting as 1-Cys thiol transferases
- Hemolysis at low blood flow rates: in-vitro and in-silico evaluation of a centrifugal blood pump
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.