MINNEAPOLIS — Diabetes can raise the risk of Alzheimer’s disease more than sixfold, warns new research.
Good control of blood sugar protects against the devastating mental disorder, say scientists. Older patients who were admitted to the hospital for both high or low levels were over six times more likely to develop it.
“For people with diabetes, both severely high and low blood sugar levels are emergencies and both extremes can largely be avoided,” says lead author professor Rachel Whitmer, of California University, Davis, in a statement. “However, when they do occur, they can lead to coma, increased hospitalization and even death.”
Diabetes is considered a risk factor for dementia by reducing blood flow to the brain. Experts estimate a third of cases could be prevented with simple lifestyle changes.
“People with type 1 diabetes are living longer than before, which may place them at risk of conditions such as dementia,” says Whitmer. “If we can potentially decrease their risk of dementia by controlling their blood sugar levels, that could have beneficial effects for individuals and public health overall.”
The study analyzed episodes of high or low blood sugar resulting in hospital emergencies, hyperglycemia and hypoglycemia, respectively. The latter can lead to unconsciousness, and the former to cardiovascular disease and blindness.
Participants admitted at some point for both complications were up to six times more likely to develop dementia — years later. Those who suffered just one of the extremes were also more prone.
Researchers tracked 2,821 participants, with an average age of 56, for seven years. Of those, 335 (12 percent) and 398 (14 percent) had a history of severe high and low blood sugar, respectively, and 87 (three percent) both. Over the study, 153 cases of dementia were diagnosed — about five percent of the population.
The risk more than doubled — and rose by 75 percent — among those with high or low blood sugar events, respectively. And it soared more than six times for those who experienced both compared to peers who had neither, after accounting for age, sex and ethnicity.
“Our findings suggest exposure to severe glycemic events may have long-term consequences on brain health and should be considered additional motivation for people with diabetes to avoid severe glycemic events throughout their lifetime,” adds Whitmer.
She points out participants only counted as having dementia if they had been diagnosed. Many cases go undiagnosed, suggesting the risks may be even higher.
Severe glycemic events can occasionally occur in the more common Type 2 form, caused by unhealthy diets and lack of exercise.
SWNS writer Mark Waghorn contributed to this report.