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. 2019 Sep;58(9):866-875.
doi: 10.1016/j.jaac.2018.11.017. Epub 2019 Mar 6.

Recurrence Risk of Autism in Siblings and Cousins: A Multinational, Population-Based Study

Stefan N Hansen  1 , Diana E Schendel  2 , Richard W Francis  3 , Gayle C Windham  4 , Michaeline Bresnahan  5 , Stephen Z Levine  6 , Abraham Reichenberg  7 , Mika Gissler  8 , Arad Kodesh  9 , Dan Bai  10 , Benjamin Hon Kei Yip  10 , Helen Leonard  3 , Sven Sandin  11 , Joseph D Buxbaum  7 , Christina Hultman  12 , Andre Sourander  13 , Emma J Glasson  3 , Kingsley Wong  3 , Rikard Öberg  12 , Erik T Parner  14
Affiliations

Recurrence Risk of Autism in Siblings and Cousins: A Multinational, Population-Based Study

Stefan N Hansen et al. J Am Acad Child Adolesc Psychiatry. 2019 Sep.

Abstract

Objective: Familial recurrence risk is an important population-level measure of the combined genetic and shared familial liability of autism spectrum disorder (ASD). Objectives were to estimate ASD recurrence risk among siblings and cousins by varying degree of relatedness and by sex.

Method: This is a population-based cohort study of livebirths from 1998 to 2007 in California, Denmark, Finland, Israel, Sweden and Western Australia followed through 2011 to 2015. Subjects were monitored for an ASD diagnosis in their older siblings or cousins (exposure) and for their ASD diagnosis (outcome). The relative recurrence risk was estimated for different sibling and cousin pairs, for each site separately and combined, and by sex.

Results: During follow-up, 29,998 cases of ASD were observed among the 2,551,918 births used to estimate recurrence in ASD and 33,769 cases of childhood autism (CA) were observed among the 6,110,942 births used to estimate CA recurrence. Compared with the risk in unaffected families, there was an 8.4-fold increase in the risk of ASD following an older sibling with ASD and a 17.4-fold increase in the risk of CA following an older sibling with CA. A 2-fold increase in the risk for cousin recurrence was observed for the 2 disorders. There also was a significant difference in sibling ASD recurrence risk by sex.

Conclusion: The present estimates of relative recurrence risks for ASD and CA will assist clinicians and families in understanding autism risk in the context of other families in their population. The observed variation by sex underlines the need to deepen the understanding of factors influencing ASD familial risk.

Keywords: autism; familial risk; longitudinal; multinational; recurrence.

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Conflict of interest statement

Disclosures:

No other conflicts of interest or financial disclosures were reported.

Figures

Figure 1.
Figure 1.
Combined Relative Recurrence Risks for ASD and CA Among Siblings and Cousins Stratified by Degree of Relatedness.
See this image and copyright information in PMC

References

    1. Elsabbagh M, Divan G, Koh YJ, et al. Global Prevalence of Autism and Other Pervasive Developmental Disorders. Autism Res 2012;5(3):160–79. - PMC - PubMed
    1. Xu G, Strathearn L, Liu B, Bao W. Prevalence of Autism Spectrum Disorder Among US Children and Adolescents, 2014–2016. JAMA 2018;319(1):81–82. - PMC - PubMed
    1. American Psychiatric Association. 2013. Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA: American Psychiatric Association.
    1. Schendel DE, Grønborg TK, Parner ET. The genetic and environmental contributions to autism: looking beyond twins. JAMA 2014;311(71):1738–9. - PubMed
    1. Rosenberg RE, Law JK, Yenokyan G, McGready J, Kaufmann WE, Law PA. Characteristics and concordance of autism spectrum disorders among 277 twin pairs. Arch Pediatr Adolesc Med 2009;163(10):907–14. - PubMed

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