Routine Vitamin D Screening Lacks Benefit

The media has been quick to discuss research findings on vitamin D supplementation’s potential role in combating osteoporosis, correcting deficiency in chronic kidney disease, improving heart health, and extending life, which raises the question of whether patients should be screened routinely for vitamin D deficiency.

The US Preventive Services Task Force (USPSTF) previously recommended against daily supplementation with vitamin D₃ ≤400 IU and calcium carbonate ≤1000 mg to prevent fracture in postmenopausal women, though it supported supplementation in adults aged 65 years or older at risk for falls. Now, the USPSTF has concluded that routine vitamin D screening is not beneficial.

The USPSTF systematically reviewed the potential benefits and harms of vitamin D screening in asymptomatic adults. The team it appointed to analyze existing research looked at 16 randomized trials of screening and treatment for vitamin D deficiency and case—control studies nested within the Women's Health Initiative. Trial participants were community-dwelling, non-pregnant adults aged 18 years and older.

Among the findings published online in the Annals of Internal Medicine were a lack of clinical trials comparing vitamin D screening to no screening, and a lack of consensus on a vitamin D deficiency definition or optimal serum level. The investigators also found that sensitivity and specificity varied by testing method and among laboratories using the same testing methods. In addition, no studies documented harms of screening for vitamin D deficiency.

Still, the USPSTF discovered that vitamin D treatment was associated with:

· Decreased mortality compared with placebo or no treatment—a benefit that disappeared when the investigators excluded trials of institutionalized persons.

· Possible decreased risk for having at least 1 fall and decreased number of falls per person, but no effect on fractures.

Patients treated with vitamin D supplements were not at increased risk for serious adverse events.

The USPSTF concluded that the “evidence on screening for vitamin D deficiency in asymptomatic adults to improve health outcomes is insufficient, and the balance of benefits and harms of screening and early intervention cannot be determined.” However, the agency acknowledged that treating vitamin D deficiency in asymptomatic patients might reduce mortality risk in institutionalized elderly patients, and it might decrease the risk for falls but not fractures.