High Doses of Vitamin D3: No Cardiac Benefits in Seniors

TOPLINE:
Higher doses of vitamin D3 supplementation did not significantly reduce cardiac biomarkers in older adults with low serum vitamin D levels. The STURDY trial found no significant differences in high-sensitivity cardiac troponin I (hs-cTnI) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) between low- and high-dose groups.
METHODOLOGY:
A total of 688 participants aged 70 years or older with low serum 25-hydroxy vitamin D levels (10-29 ng/mL) were included in the STURDY trial.
Participants were randomized to receive one of four doses of vitamin D3 supplementation: 200, 1000, 2000, or 4000 IU/d, with 200 IU/d as the reference dose.
Cardiac biomarkers, including hs-cTnI and NT-proBNP, were measured at baseline, 3 months, 12 months, and 24 months.
The trial was conducted at two community-based research institutions in the United States between July 2015 and March 2019.
The effects of vitamin D3 dose on biomarkers were assessed via mixed-effects tobit models, with participants followed up to 24 months or until study termination.
TAKEAWAY:
Higher doses of vitamin D3 supplementation did not significantly affect hs-cTnI levels compared with the low-dose group (1.6% difference; 95% CI, −5.3 to 8.9).
No significant differences were observed in NT-proBNP levels between the high-dose and low-dose groups (−1.8% difference; 95% CI, −9.3 to 6.3).
Both hs-cTnI and NT-proBNP levels increased in both low- and high-dose groups over time, with hs-cTnI increasing by 5.2% and 7.0%, respectively, and NT-proBNP increasing by 11.3% and 9.3%, respectively.
The findings suggest that higher doses of vitamin D3 supplementation do not reduce markers of subclinical cardiovascular disease in older adults with low serum vitamin D levels.
IN PRACTICE:
“We can speculate that the systemic effects of vitamin D deficiency are more profound among the very old, and there may be an inverse relationship between supplementation and inflammation. It is also possible that serum vitamin D level is a risk marker but not a risk factor for CVD risk and related underlying mechanisms.” wrote the authors of the study.
SOURCE:
The study was led by Katharine W. Rainer, MD, Beth Israel Deaconess Medical Center in Boston. It was published online in the Journal of the American College of Cardiology.
LIMITATIONS:
The study’s community-based population may limit the generalizability of the findings to populations at higher risk for cardiovascular disease. Additionally, the baseline cardiac biomarkers were lower than those in some high-risk populations, which may affect the precision of the assay performance. The study may not have had adequate power for cross-sectional and subgroup analyses. Both groups received some vitamin D3 supplementation, making it difficult to determine the impact of lower-dose supplementation vs no supplementation.
DISCLOSURES:
The study was supported by grants from the National Institute on Aging, the Office of Dietary Supplements, the Mid-Atlantic Nutrition Obesity Research Center, and the Johns Hopkins Institute for Clinical and Translational Research. Rainer disclosed receiving grants from these organizations.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.
 
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