A woman’s length of reproductive time (age at menarche to age at menopause) may provide clues to the risk of Alzheimer’s disease (AD), according to a study conducted in Sweden and published in menopause.
Estrogen has been suggested as a possible reason more women than men develop Alzheimer’s disease. The researchers examined long-term relationships between reproductive time and levels of AD biomarkers found in cerebrospinal fluid. The biomarkers the researchers looked for were Aβ42, P-tau, T-tau, and the ratio of Aβ42 / Aβ40.
They used a population-based sample of women without dementia and followed them from 1968 to 1994. All women experienced a natural menopause. The lumbar puncture was performed between 1992 and 1994. The 75 participants were born in 1908, 1914, 1918 and 1922; all but 8 were born in 1918 or 1922.
The researchers used two linear regression models to analyze the relationship between the duration of menstruation and AD biomarkers. The first model had a longer reproductive time with lower Aβ42 levels (β, -14.5; R2, 0.04; P = 0.048) and a lower ratio of Aβ42 / Aβ40 (β, -0.02; R2, 0, 1; P.) Connected = 0.0084).
In the second model, a longer reproductive period was associated with lower Aβ42 levels (β, -19.2; R2, 0.1; P = 0.011), a lower ratio of Aβ42 / Aβ40 (β, -0.02, R2, 0 , 1; P = 0.011) and higher P-tau values (β, -0.03; R2, 0.1; P = 0.011). The researchers found no associations between the length of the reproductive period and levels of CSF-T-tau.
The researchers’ results do not support previous studies that have shown that estrogen has neuroprotective benefits. The researchers found no significant association between age at menopause and AD biomarkers.
The study had limitations, including a small sample size and cumulative turnover. Only 10% of the total eligible sample underwent a lumbar puncture. This sample could generally be younger and healthier than the general population; the group was younger, had an above-average education, and members were less likely to develop dementia compared to non-participants. The researchers also suspected some memory errors.
The study “could suggest that prolonged exposure to endogenous estrogen is linked to elevated levels of AD biomarkers in the preclinical phase of AD,” the researchers concluded. “These results help understand the relationship between indicators of endogenous estrogen and AD. This could explain the higher lifetime risk of AD in women compared to men. “
Disclosure: Some study authors stated links with biotech, pharmaceutical, and / or device companies. For a full list of the author’s disclosures, see the original reference.
J. Najar, T. Hällström, A. Zettergren et al. Reproductive time and preclinical CSF markers for Alzheimer’s disease: a 25-year study. Menopause. Published online July 2, 2021. doi: 10.1097 / GME.0000000000001816
This article originally appeared on Psychiatry Advisor