“Do not test” vitamin D: new directive from the Endo company

BOSTON — New guidelines from the Endocrine Society call for limiting vitamin D supplementation beyond the recommended daily intake to specific risk groups and recommend against routine 25-hydroxyvitamin D (25(OH)D) testing ) in healthy individuals.

The evidence-based paper was presented June 3, 2024 at the Endocrine Society Annual Meeting and simultaneously published in the Journal of Clinical Endocrinology and Metabolism. He advises people who may benefit from vitamin D supplementation to include:

1. Children aged 1 to 18 years to prevent rickets and potentially reduce the risk of respiratory tract infections
2. Pregnant people to reduce the risk of maternal and fetal or neonatal complications
3. Adults over 75 years old to reduce the risk of mortality
4. Adults with prediabetes to reduce the risk of type 2 diabetes

In these groups, the recommendation is for daily (rather than intermittent) empirical vitamin D supplementation in excess of what was recommended in 2011 by the National Academy of Medicine (NAM), then the Institute of Medicine ( IOM): 600 IU. /d for people aged 1 to 70 years and 800 IU/d for people aged over 70 years. The document acknowledges that the optimal dose for these populations is not known, but it provides the dose ranges that were used in the trials cited as evidence for the recommendations.

In contrast, the document advises against consuming more vitamin D than the recommended daily intake for most healthy adults under the age of 75 and advises against testing blood levels of vitamin D in the general population, including those with obesity or darker complexion.

The guideline’s author, Anastassios G. Pittas, MD, professor of medicine at Tufts University School of Medicine in Boston, said: Medscape Medical News“This guideline refers to people who are otherwise healthy and there is no clear indication for vitamin D, such as people with already established osteoporosis. This guideline does not apply to them.”

Pittas also noted, “There is not a single question or answer about the role of vitamin D in health and disease, which is what people often want to know.” There are many questions and we cannot answer them all. »

Panel chair Marie B. Demay, MD, professor of medicine at Harvard Medical School, said: Medscape Medical News that indeed, the panel was limited by the lack of randomized clinical trial evidence to answer many important questions. “There is little data regarding defining optimal levels and optimal intake of vitamin D to prevent specific diseases… What we really need are large-scale clinical trials and biomarkers to be able to predict the outcome of the disease before it occurs.”

Overall, Demay said: “The recommendations are that populations adhere to the Recommended Dietary Intakes (NAM/IOM), and some populations will likely benefit from intake levels above (those). »

Asked to comment, session moderator Clifford J. Rosen, MD, director of clinical and translational research and senior scientist at the Maine Medical Center Research Institute, Scarborough, Maine, noted that vitamin D screening is quite common in clinical practice, but the recommendation against it makes sense.

“When clinicians measure vitamin D, they are then forced to decide what to do. That’s where questions about levels come in. And that’s a big problem. So what the panel is saying is is not to screen… This really gets to the heart of the problem, because we have no data that screening improves quality of life… Screening is probably not worth it in any group ‘age.

Rosen, author of the 2011 NAM/IOM Dietary Reference Intakes, said that since then, new data have been published regarding the role of vitamin D in mortality in people over 75, the benefit in children in regarding respiratory diseases, and the potential benefit of vitamin D during pregnancy. “Otherwise, I think we’re repeating a lot of the same things that we’ve been talking about since I was on the IOM panel 15 years ago… But I think the level of evidence and the rigor with which they have done are truly impressive. “.

However, Simeon I. Taylor, MD, professor of medicine at the University of Maryland in Baltimore, expressed disappointment that the document was limited to healthy people. “While recognizing the challenges of managing vitamin D status in patients with multiple diseases, (such as) chronic kidney disease or inflammatory bowel disease, the new guidelines do not provide sufficient guidance to practicing physicians on how to manage these complex patients.”

Additionally, Taylor said the guidelines “do not explicitly consider literature suggesting that alternative testing strategies might provide more relevant information about vitamin D status. As does variation in thyroid-binding globulin levels convinced endocrinologists not to rely on measuring total thyroxine; Interindividual variation in vitamin D-binding protein levels should be taken into account when interpreting measurements of total 25(OH)D levels. It would have been useful to explicitly consider the possible value of measuring vitamin indices independent of vitamin D binding protein. D status.”

Taylor also raised the same point as an audience member during the question-and-answer period regarding patients with osteoporosis or osteopenia. “The value and usefulness of the new guidelines would be greatly enhanced by providing guidance on how to approach this important and very broad group of individuals.”

Taylor said the paper has “several strengths, including its recognition of major limitations in the quality of relevant evidence derived from clinical trials.”

In an accompanying commentary, the guideline authors address issues of skin pigmentation and race as they relate to vitamin D metabolism, writing:

Pittas and Demay have no disclosures relevant to this clinical practice guideline. Rosen has no disclosures. Taylor is a consultant for Ionis Pharmaceuticals.

Miriam E. Tucker is a freelance journalist based in the Washington, DC area. She contributes regularly to Medscape, and other work appears in The Washington PostNPR Blows blog and Diatribe. She is on X (formerly Twitter) @MiriamETucker.