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Searching for very early precursors of autism spectrum disorders: the Hamamatsu Birth Cohort for Mothers and Children (HBC)

Published online by Cambridge University Press:  23 April 2010

K. J. Tsuchiya ,
K. Matsumoto ,
S. Suda ,
T. Miyachi ,
H. Itoh ,
N. Kanayama ,
K. Hirano ,
T. Ohzeki  and
N. Takei
K. J. Tsuchiya*
Affiliation:
Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan Department of Child Development, United Graduate School of Child Development, Osaka University, Kanazawa University and Hamamatsu University School of Medicine, Hamamatsu, Japan
K. Matsumoto
Affiliation:
Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan
S. Suda
Affiliation:
Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan
T. Miyachi
Affiliation:
Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan
H. Itoh
Affiliation:
Department of Obstetrics and Gynaecology, Hamamatsu University School of Medicine, Hamamatsu, Japan
N. Kanayama
Affiliation:
Department of Obstetrics and Gynaecology, Hamamatsu University School of Medicine, Hamamatsu, Japan
K. Hirano
Affiliation:
Department of Paediatrics, Hamamatsu University School of Medicine, Hamamatsu, Japan
T. Ohzeki
Affiliation:
Department of Child Development, United Graduate School of Child Development, Osaka University, Kanazawa University and Hamamatsu University School of Medicine, Hamamatsu, Japan Department of Paediatrics, Hamamatsu University School of Medicine, Hamamatsu, Japan
N. Takei
Affiliation:
Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan Department of Child Development, United Graduate School of Child Development, Osaka University, Kanazawa University and Hamamatsu University School of Medicine, Hamamatsu, Japan Division of Psychological Medicine, Institute of Psychiatry, King’s College London, De Crespigny Park, London SE5 8AF, UK
*
Address for correspondence: Dr K. J. Tsuchiya, Handayama 1 Higashiku, Hamamatsu 431-3192, Japan. (Email tsuchiya@hama-med.ac.jp)
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Abstract

Autism spectrum disorders (ASD) are life-long neurodevelopmental conditions. The pathophysiology is poorly understood, and the clinical diagnosis can only be made through behavioural assessments. The prevalence of ASD has increased eight-fold over the last three decades. Paralleling this rise, research interest in the disorder has been accumulating, centering on two aspects: risk factors that would explain the increase in prevalence, and precursors that could predict an emergence of ASD prior to 2 years of age. As regard factors responsible for the increased prevalence, an increasing trend of low birthweight (4.2% in 1980 v. 9.6% in 2006 at Japan) and advanced paternal age at birth are potentially implicated. To explore these issues, and to yield an early diagnostic algorithm for ASD, the authors initiated the ongoing Hamamatsu Birth Cohort for Mothers and Children (HBC) in 2007. The strengths of the HBC include frequent, direct face-to-face assessments of all the participating mothers and children during the first 4 years of life (12 assessments); this depth of assessments will disclose subtle changes in the developmental domains of individuals with ASD, which might otherwise be overlooked.

A total of 1200 pregnant women are to be recruited by the end of 2010. Assembled information comprises a range of variables related to the mother’s characteristics and child development. The comprehensiveness of the HBC will provide an informative data source that will elucidate early trajectories of children with ASD in addition to revealing detailed, developmental properties of typically developing children.

Keywords

autismbirth cohort studychild developmentJapanlow birthweightparental age
Type
Original Articles
Information
Journal of Developmental Origins of Health and Disease , Volume 1 , Issue 3 , June 2010 , pp. 158 - 173
Copyright
Copyright © Cambridge University Press and the International Society for Developmental Origins of Health and Disease 2010

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