Vitamin D Point-of-Care Testing: Faster, Simpler & More Cost-Effective

While Vitamin D is typically recognized for boosting tooth and bone health and warding off osteoporosis, studies are now finding that it can also protect us from malignancy, cardiovascular disease, diabetes, and bone disorders. Genome-wide analysis has also shown that Vitamin D plays a role in the expression of more than 200 human genes.

Uncovering Vitamin D Deficiency
Vitamin D deficiency has been found to be more widespread than previously thought. This deficiency has sparked creation of new guidelines for defining Vitamin D insufficiency and deficiency, along with recommended daily intake.

While this awareness has made testing more prevalent, its standardization is the result of advances in technology, immunoassay methods and automation. Today’s rapid, quantitative analytical techniques are faster, more cost-effective and more adaptable to a Point-of-Care setting—a win for both physicians and patients.

Recent studies have shown that a substantial percentage of the U.S. population has blood levels of 25-OH Vitamin D that approach the cut-off for Vitamin D insufficiency. This risk is multiplied when you use certain therapeutic drugs, including long-term steroids, antiepileptic drugs, L-thyroxine, gonadotropin-releasing hormone agonists, chronic lithium therapy, thiazolidinediones for diabetes, as well as antifungals, AIDS medications, and antacids.

Recommended Vitamin D Intake and Blood Levels
Daily Vitamin D3 intake recommended by the Institute of Medicine of the National Academies:

• 600 IU/day for everyone up to age 70
• 800 IU/day for everyone 71 years and older

These amounts correspond to a serum 25-OH Vitamin D level of at least 20 ng/mL.3. In addition, the Endocrine Society Task Force defines sufficient 25-OH Vitamin D as 25-50 ng/mL.

Advantages of Today’s Advances in Testing
In the past, Vitamin D has been quantified through competitive binding, using either high performance liquid chromatography (HPLC) or radioimmunoassay (RIA). For large reference laboratories, LC-MS/MS has become the gold standard. The high cost of the equipment and the staff training required make it unsuitable for point-of-care testing.

Wide availability of HPLC test kits has made HPLC-based Vitamin D analysis much more streamlined and affordable.

Advantages of immunoassay-based testing include:

• Results which correlate more closely with LC-MS/MS than the results of HPLC-based assays
• Easy-to-use, cost-effective kits are available that quickly and accurately measure 25-OH Vitamin D in plasma or serum.
• Reimbursements are available for each test conducted in-house by physician practices in the U.S., providing a faster return on the practice’s investment.
• Immediate results of monitored 25-OH Vitamin D levels make for better patient care and significantly enhance efficiencies for the physician’s practice

The precision and accuracy of today’s automated immunoassays have been shown to equal that of a centralized lab. Requiring no specialized expertise, they offer rapid results in 15 minutes or less - rather than hours later if the sample was sent out for testing.

Thanks to on-demand testing, physicians only need one face-to-face visit to test for deficiency and treat it, or monitor Vitamin D levels and adjust supplementation as needed - saving time for both the patient and the physician. This point-of-care testing allows the patient to receive proper supplementation more promptly, guards against the consequences of deficiency, and leads to greater patient satisfaction.