Dr. Suzuki also pointed out that the American Diabetes Association’s Standards of Medical Care in Diabetes 2019 does not mention age as a consideration in individualizing glycemic targets.
Instead, factors such as risk for hypoglycemia, disease duration, life expectancy, comorbidities, established vascular complications, patient preference, and resources/support systems are listed. “We need to evaluate and assess these factors individually for every patient,” he asserted.
“Older age is very heterogeneous. Some people are very robust and active, while others are sick and frail ... We need to be careful about the active, healthy people because sometimes they need more intensified treatment to prevent complications of diabetes.”
Dr. Suzuki also pointed out that people hold important positions that require good health well into their 60s and 70s. “In many countries, many older individuals with or without diabetes have responsibilities and play important roles in their societies. Diabetes can be a big barrier for them ... Sometimes it requires hospitalizations, and they need to stop business.”
He cited an observational study from a Swedish national database showing a significant difference in hospitalizations for heart failure for older adults with diabetes and HbA1c of between 6% and 7%, compared with 7%-8%, among both men and women aged 71-75 and 61-65 years. In that study, investigators found that poor glycemic control (HbA1c of more than 7%) was associated with an increased risk of hospitalization for heart failure in patients with type 2 diabetes.
“This is, of course, an observational study, so we cannot draw a conclusion, but still, it strongly suggests that lower than 7% may prevent hospitalization for heart failure in elderly people.”
Glycemic variability
Another point is that HbA1c does not reflect glycemic variability, so it’s impossible to tell just from that measure the extent to which an individual is experiencing hypoglycemia – that is, two people can have the same A1c level, yet one experiences frequent hypoglycemia whereas the other never does.
“So, determining treatment based solely on A1c may be risky,” Dr. Suzuki noted.
And recently, the availability of continuous glucose monitoring is shifting the definition of “strict” glycemic control from “average” glucose to “time in range,” which also allows for a determination of the key metric “time below range.”
Recent international guidelines advise that, for older adults, fewer than 1% of readings should be below 70 mg/dL (3.9 mmol/L), compared with fewer than 4% for most other individuals with diabetes.
Thus, “in terms of avoiding hypoglycemia, older adults have a ‘stricter’ range. In other words, less stringency for high-risk people does not always mean broader allowance range in any glycemic profiles,” Dr. Suzuki noted.
However, newer drugs that don’t increase the risk for hypoglycemia are available for patients with type 2 diabetes.
Dr. Suzuki pointed to his own 2018 study demonstrating that the dipeptidyl peptidase‐4 (DPP-4) inhibitor sitagliptin had a greater ability to reduce daily glucose fluctuations in drug-naive Japanese patients with type 2 diabetes, compared with the sulfonylurea glibenclamide.