The Disappearing Seasonality of Autism Conceptions in California
Open accessAbstract
BACKGROUND: Autism incidence and prevalence have increased dramatically in the last two decades. The autism caseload in California increased 600% between 1992 and 2006, yet there is little consensus as to the cause. Studying the seasonality of conceptions of children later diagnosed with autism may yield clues to potential etiological drivers. OBJECTIVE: To assess if the conceptions of children later diagnosed with autism cluster temporally in a systematic manner and whether any pattern of temporal clustering persists over time. METHOD: We searched for seasonality in conceptions of children later diagnosed with autism by applying a one-dimensional scan statistic with adaptive temporal windows on case and control population data from California for 1992 through 2000. We tested for potential confounding effects from known risk factors using logistic regression models. RESULTS: There is a consistent but decreasing seasonal pattern in the risk of conceiving a child later diagnosed with autism in November for the first half of the study period. Temporal clustering of autism conceptions is not an artifact of composition with respect to known risk factors for autism such as socio-economic status. CONCLUSION: There is some evidence of seasonality in the risk of conceiving a child later diagnosed with autism. Searches for environmental factors related to autism should allow for the possibility of risk factors or etiological drivers that are seasonally patterned and that appear and remain salient for a discrete number of years.
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Children conceived during winter months, when sun exposure is limited and vitamin D status is lower, were reported to have a higher risk of developing autism later in life than those conceived during summer months.
“Children conceived during the winter months, when sun exposure is limited and vitamin D status is lower, were reported to have a higher risk of developing autism later in life than those conceived during the summer months [74].”
From Vitamin D and Autism Spectrum Disorder: A Literature Review (2016) · cites this paper as [74]
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Research works printed but not linked: 2
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- Authors
- Mazumdar, S., Liu, K.-Y., Susser, E., & Bearman, P.
- Affiliations
- Columbia University (US)
- New York State Psychiatric Institute (US)
- Corresponding author
- Mazumdar, Soumya
- Venue
- PLoS ONE
- Publisher
- Public Library of Science (PLoS)
- Published
- 2012-07-30
- Volume
- 7
- Issue
- 7
- Pages
- e41265
- ISSN
- 1932-6203 (ISSN-L)
- PMC
- PMC3408493
- OpenAlex
- W2010152846
- Cited by
- 15
- References
- 65
- Citations by year
- 2023: 2 · 2017: 4 · 2016: 2 · 2015: 2 · 2014: 3 · 2013: 2
- FWCI
- 1.15
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Locations
- PLoS ONE (publishedVersion, cc-by)
- Europe PMC (PubMed Central) (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- RePEc: Research Papers in Economics (submittedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- ANU Open Research (Australian National University) (submittedVersion, cc-by)
- Columbia Academic Commons (Columbia University)
- Funders
- National Institutes of Health (DP1OD003635)
- Eunice Kennedy Shriver National Institute of Child Health and Human Development (R24HD041022)
- Topics
- Life Sciences › Neuroscience › Cognitive Neuroscience › Autism Spectrum Disorder Research
- Social Sciences › Psychology › Clinical Psychology › Family and Disability Support Research
- Health Sciences › Medicine › Psychiatry and Mental health › Child Nutrition and Feeding Issues
- Keywords
- autism spectrum disorder, seasonal variation, conception timing, temporal clustering, autism incidence, autism etiology, environmental risk factors, California
- MeSH terms
- Autistic Disorder, California, Female, Humans, Male, Models, Biological, Monte Carlo Method, Risk, Seasons, Cluster Analysis, Likelihood Functions, Logistic Models, Odds Ratio
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