Estrogen Replacement Therapy (ERT) and Alzheimer’s Disease

Estrogen Replacement Therapy (ERT) and Alzheimer’s Disease

Presentation by Huma Erboru

Peer reviewers: Navya Tanniru & Gizem Arslan

Introduction:

Late-onset Alzheimer’s disease is a clinical phenomenon that is characterized by neurodegeneration in the brain and memory loss, and its neurological symptoms usually emerge prior to the onset of clinical symptoms, around the ages of 45-55 (Alzheimer’s Association, 2020). Women make up the 2/3 of the population affected by AD (Chene et al., 2015), most probably due to estrogen loss during the menopause transition state, affecting not only women’s reproductive capabilities but also many neurological mechanisms (Brinton et al., 2015). These neurological disruptions occur in the mechanisms that are most affected by AD, such as hypometabolism (Ding et al., 2013), accumulation of Aβ plaques, which are misfolded amino peptides that are toxic to nerve cells, (Yao et al., 2012), hippocampus and prefrontal cortex deficits (Epperson et al., 2012) and mitochondrial deficiencies (Brinton, 2008).

Estrogen Replacement Therapy (ERT) has been offered as a preventative, if not treating, solution for protecting the brain against changes associated with estrogen deficiency (Brinton, 2004). Although findings are mostly controversial (e.g., Coker et al., 2009), most scientists propose starting the therapy a maximum of 5 years before the onset of menopause (Mielke, Vemuri, & Rocca, 2014), using only the estradiol form of the estrogen (Brinton, 2004) and checking with a doctor for possible side effects. (FDA, 2014) These can contribute to a beneficial outcome of the treatment.

Future Research

More clinical trials conducted with women not on yet in the menopause transition to
assess the effects of starting ERT before neurological disruptions occur
● Identifying at-risk groups, such as women with a first-degree relative diagnosed with
AD, to prevent changes from occurring
● Researching why some women don’t undergo neurological changes associated with
menopause transition to identify resilience factors

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