title: Early motor developmental milestones and schizophrenia: A systematic review and meta-analysis.
abstract: The neurodevelopmental hypothesis of schizophrenia proposes that impaired brain development is a cause of the illness. Early motor developmental milestones, such as learning to walk, are predictors of later schizophrenia but studies have not been systematically reviewed. The aim of the present systematic review and meta-analysis was to explore the association between early motor developmental milestones and the risk of adult schizophrenia. In addition, we updated a systematic review on motor function and risk of schizophrenia. The PubMed, PsycINFO and Scopus databases were searched for original research articles published up to July 2015. Motor milestones were measured between ages 0 and 13years. Random effect meta-analysis calculated effect estimates (Hedges' g) for the association between individual motor milestones and schizophrenia risk. An electronic database and selected articles reference list search identified 5990 articles after removing duplicates. Sixty-nine full text articles were assessed for eligibility of which six were included in the review. Five studies provided sufficient data for meta-analyses. The following motor milestones were significantly associated with adult schizophrenia risk: walking unsupported (g=0.46; 95% CI 0.27-0.64; p<0.001), standing unsupported (g=0.28; 0.16-0.40; p<0.001) and sitting unsupported (g=0.18; 0.05-0.31; p=0.007). Results for the milestones 'holding head up' and 'grabbing object' were not statistically significant. Delayed walking, sitting and standing unsupported were associated with adult onset schizophrenia. The findings emphasise the importance of timely achievement of these motor milestones in childhood and can contribute to the identification of individuals at risk of psychosis.
authors.affiliation: Center for Life Course Health Research, University of Oulu, Oulu, Finland; Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland. Electronic address: svetlana.filatova@oulu.fi.
authors.forename: S
authors.initials: S
authors.lastname: Filatova
authors.affiliation: Institute of Clinical Medicine (Psychiatry), University of Eastern Finland, Kuopio, Finland; Departments of Psychiatry, Kuopio University Hospital, Kuopio, South-Savonia Hospital District, Mikkeli, North Karelia Central Hospital, Joensuu, SOSTERI, Savonlinna, SOTE, Iisalmi, Lapland Central Hospital, Rovaniemi, Finland.
authors.forename: H
authors.initials: H
authors.lastname: Koivumaa-Honkanen
authors.affiliation: Information Studies, Faculty of Humanities, University of Oulu, Oulu, Finland.
authors.forename: N
authors.initials: N
authors.lastname: Hirvonen
authors.affiliation: Klinik und Poliklinik für Psychiatrie und Psychotherapie der Universität, Leipzig, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Freeman
authors.affiliation: Department of Medical Informatics, Biometry and Epidemiology - IBE, Chair for Public Health and Health Services Research, Research Unit for Biopsychosocial Health, LMU Munich, Germany.
authors.forename: I
authors.initials: I
authors.lastname: Ivandic
authors.affiliation: Neuroscience Research Unit, University of Oulu, Oulu, Finland; PEDEGO Research Unit, Child Psychiatry, University of Oulu, Finland; Clinic of Child Psychiatry, University Hospital of Oulu, Finland.
authors.forename: T
authors.initials: T
authors.lastname: Hurtig
authors.affiliation: Department of Psychiatry, University of Cambridge, Cambridge, UK; Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK.
authors.forename: G M
authors.initials: GM
authors.lastname: Khandaker
authors.affiliation: Department of Psychiatry, University of Cambridge, Cambridge, UK; Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK.
authors.forename: P B
authors.initials: PB
authors.lastname: Jones
authors.affiliation: Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland; Neuroscience Research Unit, University of Oulu, Oulu, Finland; Department of Psychiatry, Oulu University Hospital, Oulu, Finland.
authors.forename: K
authors.initials: K
authors.lastname: Moilanen
authors.affiliation: Center for Life Course Health Research, University of Oulu, Oulu, Finland; Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Miettunen
mesh_terms: D000293:Adolescent; D002648:Child; D002657:Child Development; D002675:Child, Preschool; D002658:Developmental Disabilities / Q000150:complications / Q000503:physiopathology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D009048:Motor Skills; D012559:Schizophrenia / Q000150:complications / Q000503:physiopathology*
keywords: Childhood; Delay; Early development; Motor milestones; Psychosis