Call for Research
Vitamin D tests are widely administered despite questions about their benefit for people who do not appear likely to be deficient of it.
The Endocrine Society’s newly released practice guideline recommends against routine testing of blood vitamin D levels in the general population.
Laboratory testing has increased over the years owing to studies reporting associations between blood vitamin D [25(OH)D] levels and a variety of common disorders, including musculoskeletal, metabolic, cardiovascular, malignant, autoimmune, and infectious diseases, wrote Marie B. Demay, MD, of Harvard Medical School in Boston, and coauthors in the new guideline. It was published on June 3 in The Journal of Clinical Endocrinology & Metabolism.
‘”Although a causal link between serum 25(OH)D concentrations and many disorders has not been clearly established, these associations have led to widespread supplementation with vitamin D and increased laboratory testing for 25(OH)D in the general population,” they wrote.
It’s uncertain that “any putative benefits of screening would outweigh the increased burden and cost, and whether implementation of universal 25(OH)D screening would be feasible from a societal perspective,” Dr. Demay and coauthors added.
They noted that the influential US Preventive Services Task Force also has raised doubts about widespread use of vitamin D tests.
The USPSTF has a somewhat different take from the Endocrine Society. The task force in 2021 reiterated its view that there is not enough evidence to recommend for or against widespread vitamin D testing for adults. The task force gave this test an I grade, meaning there is insufficient evidence to weigh the risks and benefits. That’s the same grade the task force gave it in 2014.
The USPSTF uses a grade of D to recommend against use of a test or service.
In an interview with this news organization, John Wong, MD, vice chair of the USPSTF, reiterated his group’s call for more research into the potential benefits and harms of vitamin D screening.
One of the challenges in addressing this issue, Dr. Wong noted, has been the variability of test results. Therefore, efforts such as the CDC’s VDSCP in improving test quality may help in eventually building up the kind of evidence base needed for the task force to offer a more definitive judgment on the tests, he said.
Wong acknowledged it must be frustrating for clinicians and patients to hear that experts don’t have the evidence needed to make a broad call about whether routine vitamin D tests are beneficial.
“We really would like to have that evidence because we recognize that it’s an important health question to help everybody in this nation stay healthy and live longer,” Dr. Wong said.
A version of this article appeared on Medscape.com.