People with type 2 diabetes or insulin resistance preceding it have an increased risk of developing Alzheimer’s-type changes in the brain, according to a study published in the journal Neurology.
Type 2 diabetes mellitus is a disorder of glucose metabolism that results in too high levels of this sugar in the blood. The disease develops when the tissues of our body lose their ability to respond properly to insulin and do not efficiently absorb glucose from the bloodstream. This phenomenon is known as insulin resistance.
Researchers from the University of Kyushu in Fukoka, Japan, tested whether type 2 diabetes could affect the appearance of changes in the brain typical of Alzheimer’s disease. These are amyloid plaques and neurofibrillary tangles. Research shows that beta-amyloid plaques cause damage to neurons, which in turn leads to symptoms such as memory and behavior disorders and personality changes.
The study included 135 elderly people (mean age 67). They all underwent several tests to help diagnose type 2 diabetes and insulin resistance. These included measurements of fasting glucose, the glucose load test, which measures glucose levels two hours after consuming 75 grams of this sugar, fasting insulin, and a test to detect insulin resistance in tissues.
For the next 10-15 years, the state of health of the respondents was monitored. Alzheimer’s symptoms appeared in 16% of respondents. of them.
After the patients died, biopsies from their brains were examined for the presence of lesions typical of Alzheimer’s.
Plates were present in a total of 65 percent. people. The analysis showed that elevated glucose levels two hours after dosing, high fasting insulin levels and test-confirmed resistance to this hormone were associated with a higher risk of the presence of platelets. These structures were present in 72 percent. people with insulin resistance and in 62 percent. people without this disorder. The relationship was particularly evident in patients with an APOE gene variant that increases the risk of Alzheimer’s disease.
It was not found, however, that disturbances in glucose metabolism were associated with the presence of neurofibrillary tangles in the brains of the examined patients.
The analysis took into account the age and gender of the patients, systolic blood pressure, cholesterol levels, body mass index (BMI), smoking addiction, physical activity and cerebral circulation disorders
According to the authors of the study, future research will help determine whether insulin resistance is the cause of the formation of amyloid plaques in the brain. If so, then by preventing or controlling type 2 diabetes well, one could counter the development of Alzheimer’s, comments lead author Dr Kensuke Sasaki.
Type 2 diabetes is closely related to an excessively caloric diet, being overweight and lack of exercise. The number of people suffering from this form of diabetes is growing at an alarming rate in the world, which is why the World Health Organization (WHO) has recognized it as a non-infectious epidemic of the XNUMXst century. Alzheimer’s disease, the most serious form of dementia, is also increasing as the population ages. Therefore, further research into the relationship between these two conditions is very important, the researchers conclude. (PAP)