Hysterectomy, Oophorectomy and Risk of Dementia: A Nationwide Historical Cohort Study

Although statistically significant, the association between premenopausal hysterectomy and early-onset dementia is uncertain due to study limitations. Premenopausal bilateral oophorectomy is associated with a higher risk, suggesting a dose effect of premature estrogen deficiency on dementia. The age-dependent effect suggests that the younger brain is probably more vulnerable to estrogen deficiency.