The FDA Announces New, Tighter Home and Healthcare Facility Standards for Blood Glucose Meter Accuracy
By Adam Brown
On January 7, the FDA announced updated standards for the accuracy of blood glucose monitors for use in both the home and healthcare facility settings. These standards – while only a draft at this point – are much tighter than the previous standards, especially for hypoglycemia and outlier values. Should they be adopted, the new requirements will raise the bar on meter accuracy in both settings. The current proposal will require that:
For home use meters, 95% of all measured blood glucose meter values must be within 15% of the reference value (a laboratory measurement); and
99% of meter values must be within 20% of the reference value
In practice, this means that home use blood glucose meters will not be able to reach the market if they produce outlier measurements – unreliable, inaccurate data points that are more than 20% off – more than 1% of the time. Additionally, patients will be able to feel confident that their blood glucose measurement is accurate (within 15%) at least 19 times out of 20, and within 20% of the true value 99 out of 100 times. The previous standards (ISO 2003) used much looser cutoffs – within 15 mg/dl (for values <75 mg/dl) and within 20% (for values >75 mg/dl). ISO 2003 standards also did not put any limits on the 5% of outlier results. Overall, we think the updated home use standards should make patients safer through the tightened requirements for outliers and hypoglycemia. With all of this progress, we still look forward to seeing a post-market surveillance program to ensure products are meeting the accuracy levels with which they were approved.
The story is a bit different for devices used in healthcare facilities, where FDA surprised many by very dramatically raising the bar on meter accuracy:
For devices used in healthcare facilities (e.g., hospitals), 99% of measured values must be within 10% of the reference value for values >70 mg/dl and within 7 mg/dl for values <70 mg/dl.
No individual result can be more than 20% off (>70 mg/dl) or 15 mg/dl off (<70 mg/dl) from the reference method.
While ever greater meter accuracy in healthcare facilities seems like a no brainer from a patient perspective, experts believe that these standards stretch beyond the limits of current technology. At the recent EASD Diabetes Technology Conference, Dr. David Sacks (NIH, Bethesda, MD) commented that “these are incredibly stringent [standards]… I think that it’s going to be very difficult for manufacturers to meet these criteria.” He added that if the FDA doesn't make them more lax, "there will be no glucose meters approved in the future.” One of the main problems is that laboratory reference devices have their own level of error – around 2% - and the FDA guidance leaves no room for the inherent imprecision of these reference methods. In fact, we have heard that many laboratory reference machines would not even meet the new requirement for 99% of values within 10%. Most experts also believe that the previous CLSI hospital standards are stringent enough – 95% of measured values must fall within 12.5% (>100 mg/dl) or 12.5 mg/dl (<100 mg/dl). In our view, further improvements in accuracy above and beyond the CLSI standards are not likely to dramatically enhance patient safety in healthcare facilities.
These extremely stringent healthcare facility standards are a major concern, since advances in hospital glucose meters beyond accuracy are critical to improving patient outcomes. For instance, we see lots of potential for next-gen meters used in healthcare settings to save nursing time and incorporate greater connectivity, better user interfaces, and anti-infection features. If no meter can meet these new accuracy requirements for healthcare facilities, we will not see any of these innovations make it to the market.
We are glad to see the FDA trying to improve glucose meters and look forward to formal adoption of the standards in whatever form they ultimately take. While the home use accuracy standards are fairly reasonable and should enhance patient safety, we expect to hear pushback against the new healthcare facility standards. Currently, the draft standards are open for public comment here until April 7, 2014; we encourage you to submit any comments or concerns. –AW/AB