Overtreating glucose levels can take a toll on diabetes patients

July 29, 2016

Mayo Clinic researchers found that beyond overtesting, focus on HbA1C levels can lead to serious harms for patients, especially as more diabetes drugs are needed to keep HbA1C within desired targets.

Beyond overtesting, focus on HbA1C levels can lead to serious harms for patients, especially as more diabetes drugs are needed to keep HbA1C within desired targets, according to a study published online in JAMA Internal Medicine.

This is particularly important for older patients with other medical conditions, according to the authors from Mayo Clinic.

The study was conducted to determine the prevalence of intensive diabetes treatment, particularly among clinically complex and older patients. More importantly, the researchers wanted to assess whether such intensive treatment increases the risk of severe hypoglycemia.

Hypoglycemia is a serious potential complication of diabetes treatment. It worsens quality of life and has been associated with cardiovascular events, dementia and death.

McCoy

“While the link between intensive treatment and hypoglycemia may seem intuitive, it has actually not been previously established among patients not receiving insulin,” said lead author Rozalina G. McCoy, MD, MS, endocrinologist and primary care physician at Mayo Clinic.

The researchers conducted a retrospective analysis of administrative, pharmacy, and laboratory data from the OptumLabs Data Warehouse from January 1, 2001 through December 31, 2013. The study included nonpregnant adults with type 2 diabetes who achieved and maintained a HbA1c of less than 7.0% without the use of insulin and had no episodes of severe hypoglycemia or hyperglycemia in the prior 12 months.

Patients were separated by whether they were considered clinically complex in order to identify patients for whom adding glucose-lowering medications is more likely to lead to treatment-related adverse events, while not providing substantial long-term benefit. Patients were considered clinically complex if they were aged 75 years or older, had end-stage kidney disease or dementia, or had 3 or more serious chronic conditions. Intensive treatment was defined as being treated with more glucose-lowering medications than clinical guidelines consider to be necessary given the HbA1c level.

Of the 31,542 patients in the study, 18.7% of clinically complex patients, and 26.5% of non-complex patients, were treated intensively. Results showed that in patients with low clinical complexity, the risk-adjusted probability of severe hypoglycemia during the study period was 1.02% with standard treatment and 1.3% with intensive treatment. In patients with high clinical complexity, intensive treatment significantly increased the risk-adjusted probability of severe hypoglycemia from 1.74% with standard treatment to 3.04% with intensive treatment.

Based on these results, researchers determined that intensive glucose-lowering therapy significantly increases the risk of severe hypoglycemia among elderly and clinically complex adults with type 2 diabetes. Patients who were younger and did not have any significant illnesses were able to tolerate intensive treatment without an increase in severe hypoglycemia risk.

“We should recognize the harms of intensive treatment and hypoglycemia, particularly when there is little likely benefit of keeping HbA1c low in the setting of limited life expectancy or multiple comorbidities,” said McCoy. “The goal of diabetes care should be achieving blood sugars in a safe range-not too high but also not too low.  It is time that we, as physicians and patients, recognize that high-quality diabetes care should emphasize not only avoiding hyperglycemia but also preventing hypoglycemia.”

McCoy believes that formulary managers have a unique opportunity to identify patients at risk for being over-treated because they know how many medications patients take, what those medications are, and the patients’ HbA1c levels.

“If patients are treated with multiple diabetes medications, formulary managers can alert physicians and patients to discuss whether they had hypoglycemia; whether treatment can be de-escalated safely; how the risk of hypoglycemia can be lowered; and how hypoglycemia can be recognized and treated,” she said.