Fertility and number of children in patients with Alzheimer's disease

Abstract

Oestrogen therapy has been suggested to have protective effects against Alzheimer's disease. The effects of natural exposure to oestrogen in cognitive disorders have rarely been studied. Assuming that nulliparous women have a higher exposure to natural oestrogen, it could be hypothesised that these women might have a lower risk of Alzheimer's disease than women who have had children. The fertility and number of children in 106 women with a diagnosis of Alzheimer's disease was examined and compared with that of 189 female subjects from two control groups with subjects without dementia. As additional control, the same comparisons were carried out for 40 male patients with Alzheimer's disease and 105 male control subjects. In female subjects, having had children was found to be associated with a diagnosis of Alzheimer's disease. This was not the case in male subjects. The number of children did not seem to affect the risk of Alzheimer's disease, neither in female nor in male subjects. Natural exposure to oestrogen seems to reduce the risk of Alzheimer's disease in women.

Influence of Variation in the Follicle-Stimulating Hormone Receptor Gene (FSHR) and Age at Menopause on the Development of Alzheimer’s Disease in Women

“…These findings suggest a mild resistance of the receptor coded by AS/AS genotype to the FSH, which in turn may lead to a subfertility status, as shown by some clinical studies for the AS/AS genotype [19,29]. The observation that the FSHR genotype possibly associated with lower fertility may confer a protection against AD is in line with previous observations that fertility represents a risk factor for AD in women [14,15,16,17,18]. In this case, the role of fertility in AD pathogenesis would be mediated by alterations in hormone levels induced by pregnancy and childbirth [15].…”

“…Previous investigations have shown that fertility, or genes involved in regulating fertility, may influence AD susceptibility in women [12,13,14,15,16,17,18]. The focus of the present study was to determine a role for FSHR as a potential AD risk factor.…”

“…Furthermore, polymorphisms of genes involved in estrogen metabolism, such as estrogen nuclear receptor genes (ESR1 and ESR2) or aromatase gene (CYP19), may modulate susceptibility to AD [1,9,10,11] and influence the age at AD onset (AAO) [12] or the course of the disease (cognitive decline) specifically in women [13]. Among non-genetic factors, past fertility (measured as parity/nulliparity or number of children) has been associated with the risk and/or the AAO in women, as well as with cognitive decline or with AD neuropathological lesions (density of neuritic plaques and neurofibrillary tangles) [14,15,16,17,18]. …”

Reproductive History and Risk of Cognitive Impairment in Elderly Women: A Cross-Sectional Study in Eastern China

“…We found that women with 5 or more times of full-term pregnancies had worse cognitive function, compared with those who had fewer times of full-term pregnancies. Previous studies generally supported that despite the high levels of estrogen during pregnancy, women with more parity were associated with the higher risk of cognitive impairment [10][11][12]27] and AD [28][29][30], due to lower circulating estrogen over lifetime than women with fewer parity or nulliparity [25,31]. In contrast, our results is the first to find that women with 3 or more times of incomplete pregnancies were not associated with the decline in cognitive performance compared with women who had fewer times of incomplete pregnancies.…”

Caractéristiques démographiques de sujets atteints de la maladie d’Alzheimer et de leurs familles

“…Nous avons retracé quatre études évaluant la fécondité dans les familles où la MA était présente. Heston et al (1981) ainsi que Ptok et al (2002) Notre analyse du rapport de masculinité a révélé des résul-tats intéressants. Les fratries des cas contiennent un excès de filles quand on les compare aux fratries des témoins.…”