ects of completed and incomplete pregnancies on the risk of Alzheimer disease

Objective To investigate the effects of completed pregnancy with childbirth and incomplete pregnancy without childbirth on the late-life cognition and the risk of Alzheimer disease (AD) in women. Methods Using the pooled data of 3,549 women provided by 2 population-based cohort studies, we conducted logistic regression analyses to examine retrospectively the associations of completed and incomplete pregnancy with the risks of mild cognitive impairment and AD. For women without dementia, we also conducted analyses of covariance to examine the associations of completed and incomplete pregnancy with Mini-Mental State Examination (MMSE) score. Results Grand multiparous women who experienced ≥5 completed pregnancies showed an ≈1.7-fold higher risk of AD than those who experienced 1 to 4 completed pregnancies (odds ratio [OR] 1.68, 95% confidence interval [CI] 1.04–2.72), while those who had incomplete pregnancies showed half the level of AD risk compared with those who never experienced an incomplete pregnancy (OR 0.43, 95% CI 0.24–0.76 for 1 incomplete pregnancy; OR 0.56, 95% CI 0.34–0.92 for ≥2 incomplete pregnancies). In women without dementia, the grand multiparous had worseMMSE scores than those with 1 to 4 completed pregnancies (p < 0.001), while those who experienced ≥1 incomplete pregnancies had better MMSE scores than those who never experienced an incomplete pregnancy (p = 0.008). Conclusions Grand multiparity was associated with high risk of AD, while incomplete pregnancy was associated with low risk of AD in late life. *These authors contributed equally to this work. From the Department of Brain and Cognitive Sciences (H.J., K.W.K.), Seoul National University College of Natural Sciences; Department of Psychiatry (J.B.B., J.W.H., D.Y.L., K.W.K.), Seoul National University, College of Medicine; Department of Neuropsychiatry (J.B.B., J.W.H., K.W.K.), Seoul National University Bundang Hospital, Seongnam, South Korea; Department of Neurology (E.D.), Faculty of Medicine, University of Thessaly, Larissa; Department of Social Medicine, Psychiatry and Neurology (N.S.), National and Kapodistrian University of Athens, Greece; Department of Neurology (N.S.), Columbia University, New York, NY; Centre for Healthy Brain Ageing (P.S.S., D.M.L.) and Dementia Collaborative Research Centre (P.S.S.), University of New South Wales, Sydney, Australia; Department of Psychiatry (T.H.K.), Yonsei University Wonju Severance Christian Hospital; Department of Psychiatry (K.P.K.), Dongguk University Gyeongju Hospital; Department of Psychiatry (B.J.K.), Gyeongsang National University, School of Medicine, Jinju; Department of Neuropsychiatry (S.G.K.), Soonchunhyang University Bucheon Hospital; Department of Psychiatry (J.L.K.), School of Medicine, Chungnam National University, Daejeon; Department of Psychiatry (S.W.M.), School of Medicine, Konkuk University and Konkuk University Chungju Hospital; Department of Neuropsychiatry (J.H.P.), Jeju National University Hospital; Department of Psychiatry, School of Medicine (S.-H.R.), Konkuk University and Konkuk University Medical Center, Seoul; Department of Neuropsychiatry (J.C.Y.), Kyunggi Provincial Hospital for the Elderly, Yongin; Department of Neuropsychiatry (D.Y.L.), Seoul National University Hospital; Department of Neuropsychiatry (D.W.L.), Inje University Sanggye Paik Hospital, Seoul; Department of Psychiatry (S.B.L., J.J.L.), Dankook University Hospital, Cheonan; Department of Psychiatry (J.H.J.), Kangwon National University, School of Medicine, Chuncheon, South Korea; Department of Nutrition and Dietetics (M.Y.), Harokopio University, Athens; Laboratory of Cognitive Neuroscience (M.H.K.), School of Psychology, Aristotle University of Thessaloniki; School of Medicine (G.M.H.), University of Thessaly, Larissa; Athens Association of Alzheimer’s Disease and Related Disorders (P.S.), Marousi, Greece; and Department of Neurology (G.M.H), Medical School, University of Cyprus, Nicosia, Cyprus. Go to Neurology.org/N for full disclosures. Funding information and disclosures deemed relevant by the authors, if any, are provided at the end of the article. Copyright © 2018 American Academy of Neurology e1 Copyright a 2018 American Academy of Neurology. Unauthorized reproduction of this article is prohibited. Published Ahead of Print on July 18, 2018 as 10.1212/WNL.0000000000006000