Curriculum · Elderly / Community care
Hypoglycaemia and cognitive decline in older adults with diabetes
What it is
In an older adult with diabetes who shows signs of mild neurocognitive impairment, hypoglycemia is one possible contributor to the condition. While it is unknown whether minor hypoglycemic events can contribute to dementia, major events have been associated with a greater risk of dementia. That is the reason the diabetes therapy itself, and not only the cognition, is looked at when such signs appear.
Causes and risk
The sulfonylurea glyburide carries a risk of significant hypoglycemia, especially in elderly patients. Glyburide in particular is listed on the Beers Criteria, and two things are said of it: first, it has the potential to cause prolonged hypoglycemia, which is what puts it on the list; second, it is a sulfonylurea, and sulfonylureas are generally added in patients with metformin failure, with weight gain and hypoglycemia as their main side effects. So it is the drug to look for on the list of an older patient with new cognitive signs, and everything else on the drug table is written the other way: metformin is weight neutral with a low risk of hypoglycemia; DPP-IV inhibitors such as sitagliptin have a low risk of hypoglycemia, are weight neutral and can be used in renal insufficiency; pioglitazone has a low risk of hypoglycemia when used alone or with metformin; and the GLP-1 receptor agonist such as exenatide has a low hypoglycemia risk when used alone or with metformin. So in an older patient on more than one agent, the sulfonylurea is the name that explains the hypoglycemia.