There’s been a serious buzz in the laboratory community recently (especially among the Point of Care [POC] community) about glucose meters. Most laboratory professionals know that glucose measurements on the average glucometer are not as reproducible as those performed on the average main lab analyzer. Some of the reason for that is simply related to issues around proper sampling and use of the glucometers. However, glucometers are only required by the FDA to have precisions of ±20%. For that reason, glucometers are not recommended to be used for diagnosing disorders, for monitoring critically ill patients, or for maintaining tight glycemic control. And yet, glucometers are routinely used nearly everywhere for all three of these purposes.
Recently, the FDA began to try to get a handle on the utilization of glucometers by coming out with two draft guidance documents (links below). By releasing these documents they have essentially reclassified glucometers into two categories: those suitable for over-the-counter (ie home) use, and those suitable for by prescription or health-care-setting(ie professional) use. The differences include:
- OTC meters – 95% of values within ±15% of reference measurement, 99% within ±20%; Professional – 99% within ±10% or ±7 mg/dL below 70 mg/dL
- OTC meters – AMR 50 – 400 mg/dL; Professional – AMR 10 – 500 mg/dL
- Professional – should also include neonatal studies
- OTC meters – labeling – for use by persons with diabetes for at home monitoring; Professional – labeling – with intended use, but not for use in critically ill or tight glycemic control
Thus the FDA has reiterated that glucometers should not be used for critically ill patients.If they are used for any purpose not specified in the package insert, their use must be classified as a moderate complexity off-label use of the glucometer, requiring the extensive validations specified by CLIA for non-FDA approved tests. These draft guidance documents have already caused the New York State Department of Health to react and send a letter to all laboratory directors stating that “…the use of glucose meters in health fairs, other community screening events, and/or critical care settings must be discontinued” until such time as CLIA validations have been performed. Thus a huge burden has been placed on the POC community in NY to either pull their POC glucometers from their facilities or validate their uses. And the rest of the country is waiting to see how it will all fall out. Glucometers are ubiquitous in the majority of health care settings and it will not be easy to meet the new FDA draft guidelines.
-Patti Jones PhD, DABCC, FACB, is the Clinical Director of the Chemistry and Metabolic Disease Laboratories at Children’s Medical Center in Dallas, TX and a Professor of Pathology at University of Texas Southwestern Medical Center in Dallas.