An estimated 25 percent of people older than 65 have type 2 diabetes, a condition in which the body cannot produce enough insulin to effectively manage blood sugar.
Insulin plays an important role in the brain, and people with prediabetes and diabetes are at increased risk of Alzheimer’s disease and cognitive decline.
Delivering insulin to the brain in the form of spray through the nose has shown to improve verbal memory and has emerged as a potential treatment for cognitive decline in the elderly.
Recently, a team of scientists at Beth Israel Deaconess Medical Center (BIDMC) has assessed the long-term effects of intranasal insulin (INI) on cognition and gait in people with and without type 2 diabetes mellitus.
“Walking speed is an important clinical predictor of well-being in the elderly that correlates with cognitive decline, hospitalizations, disability, and death,” said corresponding author Vera Novak, MD, Ph.D., of the Department of Neurology at BIDMC and an associate professor of neurology at Harvard Medical School.
At baseline, participants with diabetes walked slower and had worse cognition than the participants without diabetes, who served as a clinical reference for a normal aging population.
Inhaled Insulin Fights Against Forgetfulness
Researchers enrolled 223 participants ages 50 to 85-years-old with and without diabetes and assessed their normal and dual-task walking speeds, attention, memory and executive function, and mood using a battery of validated tests.
Half of the participants with diabetes and half without diabetes were treated with insulin, delivered intranasally via an electronic atomizer once daily. The other participants were given an inactive placebo (sterile saline) that was also delivered intranasally.
After 24-weeks of treatment participants with diabetes who received INI had faster-walking speeds during treatment and post-treatment than participants with diabetes who received a placebo.
The INI-treated participants with diabetes also demonstrated increased cerebral blood flow in the frontal lobe, and lower plasma insulin and insulin resistance compared to the placebo group, while the INI-treated participants without diabetes showed improved decision making and verbal memory.
The consistency of the trends in the data carries great implications for potential early intervention using INI to prevent or slow down the progression toward Alzheimer Disease’s related dementia.
With the increasing number of younger people having pre-diabetes, this finding on the beneficial effect of INI deserves more attention and definitive confirmation in a larger trial.
The treatment was not associated with any serious or moderate adverse events. Intranasal insulin treatment was safe in participants with type 2 diabetes treated with subcutaneous insulins.
Source: Medindia