Why Women Are Twice as Likely as Men to Develop Alzheimer's: The Key Reason

"Different Chromosomal Structure and Menopause Compared to Men"
Sharp Drop in Hormone Secretion... Analysis Suggests Link to Cognitive Decline

A study has found that women are about twice as likely as men to develop Alzheimer's disease.

The British media outlet The Independent, citing a statement from the Alzheimer's Association in the United States, reported on July 9 (local time) that "one in three older adults in the U.S. dies from dementia, including Alzheimer's disease, and about two-thirds of patients are women."

Photo to aid understanding of the article. Pixabay.

According to the report, scientists have recently found clues to why women are more likely than men to develop Alzheimer's. The main reasons are the differences in chromosomal structure compared to men, as well as menopause.

Anna Bonkoff, a doctor at Harvard Medical School and Massachusetts General Hospital, said, "When we look at neurological diseases, there is a clear difference in incidence rates between women and men." She explained that while women are more likely to experience multiple sclerosis (MS) or migraines, men are more likely to develop Parkinson's disease or brain tumors.

The X chromosome contains many genes related to brain structure and immune system regulation. Dr. Bonkoff explained that differences in the dosage of these genes may contribute to the disparity in Alzheimer's incidence rates. In particular, research has shown that women tend to survive longer after an Alzheimer's diagnosis, thanks to their second X chromosome.

Women also experience menopause in their 40s or 50s, during which the secretion of major reproductive hormones such as estrogen and progesterone drops sharply. These hormones directly affect brain function, and this change is believed to be associated with cognitive decline.

Dr. Bonkoff noted that menopause is one of the key pieces in understanding the causes of Alzheimer's disease. She added, "Aging itself is an important factor, but there is active research examining what changes occur in the immune system and the brain during menopause."

The U.S. Centers for Disease Control and Prevention (CDC) warns that while some women use hormone replacement therapy (HRT) to alleviate menopausal symptoms, HRT can cause serious side effects such as heart disease, stroke, breast cancer, blood clots, and gallbladder disease.

Professor Rachel of Harvard Medical School reported in March last year that women who received hormone replacement therapy after age 70 showed much higher accumulation of tau protein?a hallmark of Alzheimer's disease?and more severe cognitive decline. Professor Rachel emphasized, "Most current analyses rely on existing data, which has its limitations," and added, "We need new research designs that can track in real time how blood, the brain, and cognitive function change before and after menopause."