June 19, 2013
Dementia Linked to Hypoglycemia in Older Patients
With Diabetes

San Francisco—Is the intensive focus on using medications to lower blood sugar causing significant adverse events in older patients?

A new study from the University of California, San Francisco, suggests it could be. Research published by JAMA Internal Medicine found a bidirectional association between hypoglycemic events and dementia in older adults with diabetes mellitus (DM).

Background in the article notes increasing evidence that diabetes may increase the risk for developing cognitive impairment, including Alzheimer’s disease and vascular dementia, and greater research interest on whether DM treatment can prevent cognitive decline.

Noting that, “hypoglycemia commonly occurs in patients with diabetes mellitus (DM) and may negatively influence cognitive performance,” the authors said they embarked on the study because previous research has been inconclusive in the relationship between low blood sugar and dementia.

For the study, researchers looked at 783 older adults with DM, with an average age of 74 years. Over 12 years of follow-up, 61 patients, 7.8%, had a reported hypoglycemic event and 148, 18.9%, developed dementia.

They found that patients who experienced a hypoglycemic event had twice the risk for developing dementia compared with those who did not have a hypoglycemic event—34.4% versus 17.6%. In addition, older adults with DM who developed dementia had a greater risk for having a subsequent hypoglycemic event compared with patients who did not develop dementia, 14.2% versus 6.3%.

“Among older adults with DM who were without evidence of cognitive impairment at study baseline, we found that clinically significant hypoglycemia was associated with a two-fold increased risk for developing dementia … Similarly, participants with dementia were more likely to experience a severe hypoglycemic event,” the authors note, adding that the association remained even after adjustment for age, sex, educational level, race/ethnicity, comorbidities, and other covariates.

“These results provide evidence for a reciprocal association between hypoglycemia and dementia among older adults with DM,” the researchers conclude.

In a commentary accompanying the article, Kasia J. Lipska, MD, MHS, of the Yale University School of Medicine in New Haven, Connecticut, and Victor M. Montor, MD, of the Mayo Clinic in Rochester, Minnesota, said “decisions about the intensity and type of antihyperglycemic therapy must take into account the harms of hypoglycemia.”

“Hypoglycemia is a major adverse consequence of glucose-lowering therapy in patients with type 2 diabetes mellitus (DM),” the commentators write. “For the last decade, DM care guidelines and quality metrics have been almost exclusively focused on prevention of hyperglycemia and its complications. However, target-based glucose lowering can potentially lead to one-size-fits-all clinical practice and result in adverse events. Involving patients in these treatment decisions may favorably shift the current glucose-centric paradigm to a more holistic patient-centered one.”

Noting that age-related changes in renal function and drug clearance could be contributing to the vulnerability to hypoglycemia, they called for efforts to mitigate the risks “to improve quality of life and potentially prevent the associated adverse events.”

U.S. Pharmacist Social Connect