Patients with Controlled Diabetes Often Over-Tested, Over-Treated

October 13th, 2016

ROCHESTER, MN – Physicians who too often test patients with type 2 diabetes contribute to over-treatment with hypoglycemic drugs, according to a new study.

The report, published recently in The British Medical Journal (BMJ,) discusses the U.S. trend of over-testing glycated hemoglobin (HbA1c) levels in adult patients with type 2 diabetes.

The study team from the Mayo Clinic argued that over-testing not only adds unnecessary expense and time burden for patients and providers, but it also results in over-treatment, which increases potential health complications.

However, physicians might just be following guidelines as best they can, according to the authors. The study points out that professional societies and regulatory bodies aren’t specific on type 2 diabetes monitoring and treatment protocols. While lower thresholds of testing frequencies often are discussed, the definition of “too much” isn’t offered.

The study advises that for adult patients who are not using insulin, have stable glycemic control within the recommended targets, and have no history of severe hypoglycemia or hyperglycemia, checking once or twice a year is sufficient.

The prevalence in practice is much higher, however, according to study results. Using de-identified administrative, pharmacy, and laboratory data from the OptumLabs Data Warehouse (OLDW) from 2001 to 2011, the researchers examined a national cohort of 31,545 non-pregnant adults with controlled noninsulin-treated type 2 diabetes. Slightly more than half of them achieved and maintained the recommended less than 7% HbA1c level and were tested three or four times a year, while 6% were tested five or more times.

Excessive testing increased the odds of over-treatment with one or more drugs, despite normal HbA1c levels. Specifically, compared with guideline-recommended testing, excessive testing was associated with treatment intensification by an odds ratio of 1.35.

"Our findings are concerning, especially as we focus more on improving the value of care we deliver to our patients -- not only ensuring maximal benefit, but also being mindful of waste, patient burden, and healthcare costs," lead investigator Rozalina McCoy, MD, a Mayo Clinic primary care physician and endocrinologist, explained in a press release. "As providers, we must be ever vigilant to provide the right testing and treatment to our patients at the right times -- both for their well-being and to ensure the best value in the healthcare we provide."

According to study authors, potential reasons for more frequent testing include:

• clinical uncertainty;
• misunderstanding of the nature of the test – i.e., not realizing that HbA1c represents a three-month average of glycemic control;
• a misplaced desire for more comprehensive care;
• fragmentation of care;
• efforts to meet regulatory demands such as a performance metrics; or
• internal performance tracking.

The study also found that patients receiving bundled testing, such as cholesterol, creatinine, and HbA1c tests in the same day, were less likely to be over-tested.