Walter A Rocca1, Brandon R Grossardt, Lynne T Shuster. 1. Division of Epidemiology, Department of Health Sciences Research, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA. rocca@mayo.edu
Abstract
BACKGROUND: The concept of neuroprotective effects of estrogen in women remains controversial. OBJECTIVE: To explore the timing hypothesis in relation to cognitive aging and dementia. METHODS: We reviewed existing literature, conducted some reanalyses, and combined results graphically. RESULTS: Current evidence suggests that estrogen may have either protective effects or harmful effects on the brain depending on age, type of menopause (natural versus surgical), or stage of menopause. The comparison of women with ovarian conservation versus women who underwent bilateral oophorectomy provided evidence for a sizeable neuroprotective effect of estrogen in women in the premenopausal years (most commonly before age 50 years). Several case-control studies and cohort studies also showed a neuroprotective effect in women who received estrogen treatment in the early postmenopausal phase (most commonly at ages 50-60 years). However, recent clinical trials showed that women who initiated estrogen treatment in the late postmenopausal phase (ages 65-79 years) experienced an increased risk of dementia and cognitive decline. CONCLUSION: The neuroprotective effects of estrogen depend on age, type of menopause, and stage of menopause (timing hypothesis). Copyright 2010 S. Karger AG, Basel.
BACKGROUND: The concept of neuroprotective effects of estrogen in women remains controversial. OBJECTIVE: To explore the timing hypothesis in relation to cognitive aging and dementia. METHODS: We reviewed existing literature, conducted some reanalyses, and combined results graphically. RESULTS: Current evidence suggests that estrogen may have either protective effects or harmful effects on the brain depending on age, type of menopause (natural versus surgical), or stage of menopause. The comparison of women with ovarian conservation versus women who underwent bilateral oophorectomy provided evidence for a sizeable neuroprotective effect of estrogen in women in the premenopausal years (most commonly before age 50 years). Several case-control studies and cohort studies also showed a neuroprotective effect in women who received estrogen treatment in the early postmenopausal phase (most commonly at ages 50-60 years). However, recent clinical trials showed that women who initiated estrogen treatment in the late postmenopausal phase (ages 65-79 years) experienced an increased risk of dementia and cognitive decline. CONCLUSION: The neuroprotective effects of estrogen depend on age, type of menopause, and stage of menopause (timing hypothesis). Copyright 2010 S. Karger AG, Basel.
Authors: W A Rocca; J H Bower; D M Maraganore; J E Ahlskog; B R Grossardt; M de Andrade; L J Melton Journal: Neurology Date: 2007-08-29 Impact factor: 9.910
Authors: Sally A Shumaker; Claudine Legault; Stephen R Rapp; Leon Thal; Robert B Wallace; Judith K Ockene; Susan L Hendrix; Beverly N Jones; Annlouise R Assaf; Rebecca D Jackson; Jane Morley Kotchen; Sylvia Wassertheil-Smoller; Jean Wactawski-Wende Journal: JAMA Date: 2003-05-28 Impact factor: 56.272
Authors: Sally A Shumaker; Claudine Legault; Lewis Kuller; Stephen R Rapp; Leon Thal; Dorothy S Lane; Howard Fillit; Marcia L Stefanick; Susan L Hendrix; Cora E Lewis; Kamal Masaki; Laura H Coker Journal: JAMA Date: 2004-06-23 Impact factor: 56.272
Authors: Caroline C Smith; Lindsey C Vedder; Amy R Nelson; Teruko M Bredemann; Lori L McMahon Journal: Proc Natl Acad Sci U S A Date: 2010-10-25 Impact factor: 11.205
Authors: Jennifer Weuve; Eric J Tchetgen Tchetgen; M Maria Glymour; Todd L Beck; Neelum T Aggarwal; Robert S Wilson; Denis A Evans; Carlos F Mendes de Leon Journal: Epidemiology Date: 2012-01 Impact factor: 4.822