What factors modify the effect of monthly bolus dose vitamin D supplementation on 25-hydroxyvitamin D concentrations?. Issue 201 (July 2020)

• Record Type: Journal Article
• Authors: Wu, Zhenqiang; Camargo, Carlos A.; Reid, Ian R.; Beros, Angela; Sluyter, John D.; Waayer, Debbie; Lawes, Carlene M.M.; Toop, Les; Khaw, Kay-Tee; Scragg, Robert
• Is Part Of: Journal of steroid biochemistry and molecular biology. Issue 201(2020)
• Publication Date: 2020-07
• Subjects: Randomized controlled trial -- 25-Hydroxyvitamin D -- Vitamin D supplementation -- Effect modification; Steroid hormones -- Periodicals; Biochemistry -- Periodicals; Hormones -- Periodicals; Molecular Biology -- Periodicals; Hormones stéroïdes -- Périodiques; Steroid hormones; Periodicals; 572.579
• DOI: 10.1016/j.jsbmb.2020.105687
• Languages: English
• ISSNs: 0960-0760

Abstract

Highlights: The 25(OH)D response to vitamin D supplementation differs between studies. There is little research on factors that modify the 25(OH)D response to vitamin D. We investigated effect modifiers in participants in a vitamin D supplement trial. Age, sex, 25(OH)D, BMI and sun exposure modify the 25(OH)D response to vitamin D. Abstract: The increasing use of vitamin D supplements has stimulated interest in identifying factors that may modify the effect of supplementation on circulating 25-hydroxyvitamin D (25(OH)D) concentrations. Such information is of potential interest to researchers, clinicians and patients when deciding on bolus dose of vitamin D supplementation. We carried out a large randomized controlled trial of 5110 adults aged 50–84 years, of European/Other (84%), Polynesian (11%) and Asian (5%) ethnicity, to whom we gave a standard dose of vitamin D3 supplements (200, 000 IU initially, then 100, 000 IU monthly) which was taken with high adherence. All participants provided a baseline blood sample, and follow-up blood samples were collected at 6 months and annually for 3 years in a random sample of 441 participants, and also at 2 years in 413 participants enrolled in a bone density sub-study. Serum 25(OH)D was measured by LC/MSMS. Mixed model analyses were carried out on all 854 participants providing follow-up blood samples in multivariable models that included age, sex, ethnicity, body mass index (kg/m 2 ), tobacco smoking, alcohol intake, physical activity, sun exposure, season, medical prescription of high-dose vitamin D3 (Cal.D.Forte tablets), asthma/COPD and the study treatment (vitamin D or placebo). The adjusted mean difference in 25(OH)D in the follow-up points between vitamin D supplementation and placebo groups was inversely related (all p for interaction <0.05) to baseline 25(OH)D, BMI, and hours of sun exposure, and higher in females, elders, and those with high frequency of alcohol, medical prescription of vitamin D, and asthma/COPD. The mean difference was not significantly related to ethnicity ( p = 0.12), tobacco ( p = 0.34), and vigorous activity ( p = 0.33). In summary, these data show that vitamin D status, BMI, sun exposure hours, sex and asthma/COPD modify the 25(OH)D response to vitamin D supplementation. By contrast, ethnicity, tobacco smoking, and vigorous activity do not.