A common procedure used by women to alleviate menopausal symptoms may actually elevate their risk of developing dementia, a new observational study has revealed.
With approximately 44 percent (pdf) of women resorting to estrogen and progestin hormone replacement therapy (HRT) to counter hot flashes, night sweats, mood changes, and other menopause-related side effects, the findings have sparked discussions among experts, urging a thorough investigation into the potential implications for women’s health.
HRT Increased Dementia Risk in Women Aged 50 to 60 Within 20 Years
The new study analyzing data from over 60,000 Danish women found links between HRT and increased risk of dementia. The research examined medical records of nearly 5,600 women aged 50 to 60 diagnosed with dementia or Alzheimer’s between 2000 and 2018, comparing them to over 55,000 women without these conditions.
The findings showed exposure to commonly prescribed HRT containing estrogen and progestin was associated with a greater incidence of overall dementia, late-onset dementia, and Alzheimer’s disease. Longer HRT use also correlated with higher dementia risk.
On average, dementia diagnosis occurred around age 70. Even short-term HRT use appeared to increase dementia rates for those starting treatment at 55 or younger.
Women Shouldn’t Stop Hormone Therapy: Expert
“The bottom line” is that this study had multiple flaws and “no changes should be made in clinical practice based on the findings,” Dr. Stephanie Faubion, medical director of The North American Menopause Society, a nonprofit organization aiming to help women during midlife, told The Epoch Times.
This study’s primary limitation lies in its observational nature, which can establish associations between variables but cannot prove causation like a randomized control trial (RCT). Some menopausal symptoms that prompt HRT usage are also linked to increased dementia risk.
Potential confounding factors in the study may be responsible for a “spurious signal for higher dementia risk” in younger women using HRT for either short or long durations, according to Menopause Society experts.
“Confounding by indication may also affect observational findings because vasomotor symptoms, particularly during sleep, are associated with a higher volume of white matter hyperintensity—a marker of poor brain vascular health,” they told The Epoch Times in an email. Poor brain vascular health is reduced blood flow to different areas of the brain, leading to damage that contributes to cognitive decline.
“The benefits of hormone therapy continue to outweigh the risks for most women who are under the age of 60 years and within 10 years of menopause onset,” Dr. Faubion said.
HRT Timing Impacts Alzheimer’s Risk, Contradicting Previous Studies
The new study presents conflicting findings on the relationship between HRT and Alzheimer’s risk.
It contradicts other recent research that found early HRT use around menopause onset might reduce Alzheimer’s risk in some women.
The study by Mass General Brigham (MGB), published in the Journal of the American Medical Association, found early menopause to be a risk factor for Alzheimer’s dementia, but women prescribed HRT around this time did not show increased dementia risk.
MGB researchers used positron emission tomography (PET) neuroimaging to link Alzheimer’s-related proteins (beta-amyloid and tau) to age at menopause and HRT use. This indicates that delaying HRT initiation may have adverse cognitive effects.
The findings support administering hormone therapy close to menopause onset rather than years after.
The association between abnormal levels of beta-amyloid and tau was much more robust in those with earlier menopause onset, even after adjusting for causes of premature menopause, such as smoking, removal of the ovaries, and genetic risk factors for Alzheimer’s, the study found.
“When it comes to hormone therapy, timing is everything,” Dr. JoAnn Manson, chief of the Division of Preventive Medicine at Brigham and Women’s Hospital and coauthor of the study, said in a press statement.