The results of a large study suggest that menopausal hormone therapy is linked to a higher dementia and Alzheimer’s rate.1✅ JOURNAL REFERENCE
DOI: 10.1136/bmj-2022-072770
An increase in the rate was observed in individuals making use of menopausal hormone therapy long term, as well as in those making use of them short term at about 55 years or younger.
Menopausal hormone therapy, commonly known as HRT, is used to alleviate typical menopausal symptoms which include night sweats and hot flashes. Treatments include tablets that contain estrogen only, or a combination of progestogen and estrogen, as well as skin patches, creams, and gels.
Observational studies have revealed that continued use of menopausal hormone therapy is linked to the risk of dementia, which confirms the large Women’s Health Initiative Memory Study results.
But the impact of using menopausal hormone therapy short term around the menopause age, as is currently advised, still has to be thoroughly investigated. The impact of different treatment regimens on dementia risk is also uncertain.
The researchers wanted to fill these knowledge gaps by evaluating the connection between the use of combined estrogen and synthetic progestogen known as progestin treatment and the development of dementia based on the kind of hormone treatment, how long used, and age when used.
The researchers identified 5,589 dementia cases making use of national registry data and 55,890 age-matched controls free of dementia between 2000 and 2018 from women between the ages of 50 and 60 in 2000 without any dementia history and no underlying reason that prevented menopausal hormone therapy use.
Other relevant factors such as thyroid disease, diabetes, hypertension, income, and education were also considered.
The diagnosis age was 70 years on average. Before being diagnosed, 1,782 cases and 16,154 controls had received estrogen-progestin treatment from an age of 53 years on average. The duration of use was 3.6 years for controls and 3.8 years for cases on average.
The results reveal that, in comparison to individuals who had never made use of treatment, individuals who had received estrogen-progestin treatment had a 24% increase in the rate of developing dementia and Alzheimer’s, even in women who had been given treatment at 55 years or younger.
Higher rates were seen with longer use, which ranged from 21% for 12 months or less to 74% for over 12 years. The increase in dementia rate was comparable between continuous daily estrogen and progestin treatment and cyclic treatment of daily estrogen with progestin used 10 to 14 days a month. Progestin therapy on its own and vaginal estrogen on its own weren’t linked to dementia.
Cause can’t be established as this is an observational study, and vascular dementia wasn’t able to be isolated from other kinds of dementia or tablets be distinguished between other methods of taking hormone therapy, which include patches.
It also can’t be ruled out that women making use of hormone therapy are predisposed to dementia as well as menopausal vasomotor symptoms such as night sweats and hot flashes.
This was however a large study with a long follow-up time using high-quality treatment data.
The researchers were also able to examine continuous and cyclic hormone formulations separately, and also the age when menopausal hormone therapy started and treatment duration, allowing for analysis of a significant overlooked aspect of this topic such as dementia risk in individuals using menopausal hormone treatment short term around the age of onset of menopause.