Abdominal fat predicts Alzheimer’s disease 20 years before symptoms appear

Researchers have linked a certain type of fat deposits to abnormal proteins in the brain that are hallmarks of Alzheimer’s disease. up to 20 years before the first symptoms of dementia appear, according to research presented today at the annual meeting of the Radiological Society of North America (RSNA). The researchers emphasized that lifestyle changes aimed at reducing the amount of this fat may influence the development of Alzheimer’s disease.

Mahsa DolatshahiThe lead author of the study, explains in a statement: “This crucial result was found because we examined the pathology of Alzheimer’s disease as early as middle age, between the ages of 40 and 50, when the pathology of the disease is in the early stages.” . stages and potential modifications such as weight loss and reduction visceral fat

— which accumulate in the deep part of the abdominal cavity, in the space surrounding the organs — are more effective as a means of preventing or delaying the onset of disease,” said the researcher from the Mallinckrodt Institute of Radiology (MIR) at Washington University School of Medicine in St. Louis, Missouri.

Increased amyloid and tau

In the study, scientists focused on the connection between modifiable factors lifestyle-related such as obesity, body fat distribution and metabolic aspects, and Alzheimer’s disease pathology.

“We examined the association of BMI, visceral fat, subcutaneous fat, liver fat fraction, thigh and muscle fat, and insulin and HDL (good cholesterol) resistance with amyloid and tau deposition in Alzheimer’s disease,” said Dr. Dolatshahi.

The results showed that higher levels of visceral fat were associated with amyloid increasewhich explains 77% of the effect of high BMI on amyloid accumulation. Other types of fat do not explain the increase in obesity-related Alzheimer’s disease.

“Our study found that more visceral fat was associated with higher PET levels of two abnormal proteins characteristic of Alzheimer’s disease: amyloid and tau“, stated Dr. Dolatshahi. “To our knowledge, our study is the only one to demonstrate these results in midlife, when our participants are decades away from developing the first symptoms of Alzheimer’s dementia.”

insulin resistance

The study also showed that greater resistance to insulin and lower HDL levels were associated with increased brain amyloid levels. The effect of visceral fat on amyloid pathology was partially reduced in people with higher HDL levels.

In this study, the researchers performed an MRI. magnetic brain And press with cognitively normal middle-aged individuals across a wide range of BMIs and compared total and regional cerebral blood flow on brain MRI in individuals with high and low visceral and subcutaneous fat. The high visceral fat group had lower total cerebral blood flow. No significant differences in cerebral blood flow were observed between the high and low subcutaneous fat groups.