(HealthDay News) – Patients with type 2 diabetes mellitus (T2DM) who initiate treatment with metformin have a lower risk of developing dementia, according to a study presented at the annual Alzheimer’s Association International Conference, held from July 13–18 in Boston.
Rachel Whitmer, PhD, and colleagues from Kaiser Permanente in Oakland, CA, analyzed the association between T2DM and dementia in 14,891 T2DM patients (≥55 years) in the Kaiser Permanente Diabetes Registry who initiated diabetes monotherapy between 1999 and 2001.
During five years of follow up, 1,487 patients (9.9%) were diagnosed with dementia, of whom 55% had initiated metformin, 25% had initiated sulfonylureas, 14% had initiated thiazolidinediones, and 6% had initiated insulin. Compared with the group taking sulfonylureas, the researchers found that only the group taking metformin had a lower risk of dementia (hazard ratio, 0.79) after adjusting for age, race, education and diabetes duration. Compared with the group taking metformin, the groups taking sulfonylureas, thiazolidinediones, and insulin had an increased risk of dementia (hazard ratios ranging from 1.18–1.28). Further adjusting for glycosylated hemoglobin produced similar results.
“In diabetic patients, those initiating metformin had a five year reduced risk of dementia in comparison to patients initiating other therapies,” Whitmer and colleagues conclude. “These results are preliminary evidence that benefits of insulin sensitizers may extend beyond glycemic control to neurocognitive health.”