The Menopause Charity
Can HRT help protect against Alzheimer’s and Dementia?
Body-identical HRT has already been shown to help reduce the long-term risk for women of osteoporosis, heart disease and even colon cancer. Now, new research coming out of America has shown that women who took transdermal, body-identical estrogen and progesterone were 73 per cent less likely to get dementia and other brain-degenerating diseases.[i]
It’s an amazing, and heartening figure, since two out of three Alzheimer’s patients are female, and it is becoming increasingly clear to neurologists and menopause specialists that keeping your brain in good health – by replacing hormones, eating well, and taking regular exercise – lowers the chances of the amyloid plaques which cause Alzheimer’s building up in the brain. Think of it as similar to keeping your teeth clean and healthy to avoid plaque building up and causing decay.
[i] https://alz-journals.onlinelibrary.wiley.com/doi/full/10.1002/trc2.12174
A massive American study of women’s health records
The new observational American research was led by Dr Roberta Diaz Brinton of Arizona University, and studied the health insurance records of almost 400,000 women over 45 for ten years. Even women using the older oral combined HRT showed a 42 per reduced risk of neuro-degenerative diseases like Alzheimer’s and Parkinson’s Disease, but women on transdermal estrogen had a 73 per cent reduction in dementia, and a 55 per cent reduction in Multiple Sclerosis compared to women not using HRT. The longer women stayed on HRT, the better the results.
Dr Brinton says: “The critical factor is starting treatment when you have menopausal symptoms.” The idea is to replace hormones as they start to fall, as brain changes begin in perimenopause. Giving HRT suddenly, years afterwards when estrogen receptors have shut down, is often too late. Brinton says symptoms like hot flushes and memory loss are “the canary in the coal mine”, and women who experience serious symptoms should consider HRT or other estrogen replacement early on.
Early hysterectomy and oophorectomy increase dementia risk
The protective powers of body-identical HRT make sense when you look at what happens to women who have early hysterectomies or oophorectomies – removal of the uterus and the ovaries – and lose their hormones. A new analysis of patients in the UK Biobank shows that women who have hysterectomies slightly increase their risk of dementia, and women who lost their ovaries double their risk of dementia[i] – unless they take HRT.
Is there a “critical window” for starting HRT?
In Brinton’s observational study, women were started by their doctors on HRT for symptoms during menopause – but in previous clinical trials including the Women’s Health Initiative, post-menopausal women who had no symptoms were given HRT, and the average starting age was 63. The WHI HRT included the synthetic progestogen medroxyprogesterone acetate, and women showed a small increase in dementia.[ii] “These clinical trials were conducted in postmenopausal women with no menopausal symptoms and who had aged passed the “critical window” for efficacy of hormone therapy to impact estrogenic action in the brain,” says the Brinton report. Also, the women in the WHI trial were not on body-identical HRT.
A recent British analysis of medical records showed using HRT did not increase dementia, and indeed estrogen-only therapy reduced dementia.[iii] The study was mostly on older forms of HRT, and did not include the new body-identical progesterone. Interestingly, pills which included the progestogen dydrogesterone, which has a better safety profile than most synthetic progestogens, also decreased dementia risk.
Are women on HRT generally healthier?
There is the “healthy user bias” as women who take HRT are more likely to be better educated, healthier, and less economically deprived. But in Brinton’s observational study, all the women insured were relatively healthy, with similar mortality risks.
What happens to the brain in menopause?
Paying attention to the risks of dementia early could be a no-brainer for women, as studies of the perimenopausal and menopausal brain show the effects of deprivation of hormones. Dr Brinton has worked alongside Dr Lisa Mosconi, author of The XX Brain, studying brain scans of women before and after menopause. “Menopause impacts human brain structure, connectivity, energy metabolism, and amyloid-beta deposition,” they concluded in research in Nature[iv], and the changes begin in perimenopause, when most women are in their forties.
So forewarned is forearmed.
[i] https://www.healio.com/news/womens-health-ob-gyn/20220406/study-shows-certain-reproductive-factors-increase-dementia-risk-in-women
[ii] https://jamanetwork.com/journals/jama/fullarticle/196628
[iii] https://www.bmj.com/content/374/bmj.n2182
[iv] https://www.nature.com/articles/s41598-021-90084-y
