Polyunsaturated Fatty Acids in Newborn Bloodspots: Associations With Autism Spectrum Disorder and Correlation With Maternal Serum Levels.

We conducted a population-based case-control study to examine newborn polyunsaturated fatty acid (PUFA) levels in association with autism spectrum disorder (ASD) and assess PUFA correlation across two time points. ASD cases (n = 200) were identified through the Department of Developmental Services and matched to live-birth population controls (n = 200) on birth month, year (2010-2011), and sex. Nonesterified PUFAs were measured by isotope dilution liquid chromatography-high resolution mass spectrometry from archived newborn dried blood spots and maternal mid-pregnancy serum samples. Crude and adjusted conditional logistic regression models were used to examine the association between neonatal PUFA levels, categorized in quartiles and according to distributional extremes, and ASD. Cubic splines were utilized to examine nonlinear relationships between continuous neonatal PUFAs and ASD. The correlation between neonatal and maternal levels was examined using Pearson correlation coefficients. In adjusted analyses of neonatal PUFA levels, no clear trends emerged, though there was an elevated odds ratio of ASD for the third quartile of linoleic acid, relative to the first (adjusted odds ratio = 2.49, 95% confidence interval: 1.31, 4.70). Cubic spline analysis suggested a nonlinear association between linoleic acid and ASD, though this was not robust to sensitivity analyses. While individual PUFAs were significantly correlated with one another within a given time point, aside from docohexaseanoic acid, PUFAs were not correlated across maternal and neonatal samples. Overall, our findings do not support an association between neonatal PUFA levels and ASD. Future work should confirm and expand these findings by examining associations with phenotypic subgroups and considering PUFAs in other time points. LAY SUMMARY: In this study, we examined whether levels of fats known as polyunsaturated fatty acids, measured in newborns, were related to later child diagnosis of autism spectrum disorder (ASD). Overall, we did not find strong evidence for hypothesized reduction in risk of ASD based on newborn levels of these fats. Future studies in larger samples and considering other time points may be useful to explain whether these fats are important in brain development related to ASD. Autism Res 2020, 13: 1601-1613. © 2020 International Society for Autism Research, Wiley Periodicals, Inc.