WASHINGTON — Elderly people with type 1 diabetes were 83% more likely to develop dementia compared with those without the disease, findings from a study that involved more than 400,000 people older than aged 60 years indicate.
Although it’s known that type 2 diabetes increases dementia risk, little was known about the effect of type 1 diabetes on cognitive aging until now.
“Elderly people with type 1 diabetes are a population that is unique from elderly people with type 2 diabetes,” said Rachel Whitmer, PhD, of Kaiser Permanente Division of Research in Oakland, California. “They have a much younger age of diabetes onset, continuous insulin treatment, more frequent severe hypoglycemic episodes, but fewer vascular risk factors.”
To determine the prevalence of new dementia diagnoses, she and colleagues followed 490,344 people aged older than 60 years with no prior history of dementia, who were part of the Kaiser Permanente Northern California health system during a 12 year period. A total of 230 participants had type 1 diabetes. Whitmer and colleagues presented the results at the 2015 Alzheimer’s Association International Conference.
During the follow-up period, dementia was diagnosed in 16% of patients with type 1 diabetes and in 12% of patients without type 1 diabetes.
After adjusting for stroke, peripheral artery disease, and hypertension, those with type 1 diabetes were 61% more likely to develop dementia than those without the disease, the researchers found.
When people with type 2 diabetes were excluded from the comparison group, the relationship between type 1 diabetes and dementia was even stronger, with 73% more likely to develop dementia after adjustment.
“Since management of type 1 diabetes requires vigilance and constant self-care, cognitive impairment poses a particular threat to this vulnerable population,” Whitmer said. “More research is needed to identify risk and protective factors for Alzheimer’s and other dementias in this group that is newly entering the aging population.”
- Whitmer R et al. #5543. “Type 1 Diabetes and Risk of Dementia in Late Life: The Kaiser Diabetes & Cognitive Aging Study.” Presented at: AAIC 2015. June 18-23, 2015; Washington, D.C.