Autism (or autism spectrum disorder [ASD]) is an often disabling childhood neurologic condition of mostly unknown cause. It is commonly diagnosed at 3 or 4 years of age.We explored whether there was an association of any analytes measured by newborn screening tests with a later diagnosis of ASD. A database was compiled of 3-5 year-old patients with any ASD diagnosis in the Texas Medicaid system in 2010-2012. Two controls (without any ASD diagnosis) were matched to each case by infant sex and birth year/month. All study subjects were linked to their 2007-2009 birth and newborn screening laboratory records, including values for 36 analytes or analyte ratios. We examined the association of analytes/ratios with a later diagnosis of ASD. Among 3,258 cases and 6,838 controls, seven analytes (e.g., 17-hydroxyprogesterone, acylcarnitines) were associated with a later ASD diagnosis. In this exploratory study, an ASD diagnosis was associated with 7 of 36 newborn screening analytes/ratios. These findings should be replicated in other population-based datasets. K E Y W O R D Sautism, autism spectrum disorder, case control study, epidemiology, newborn screening 1 | BACKGROUND In 2012, the prevalence of autism spectrum disorder (ASD) among 8-year old children within the United States was 1 in 68, or roughly 1.5%. Estimates suggest that ASD appears to have increased over Abbreviations: 95% CI, 95% confidence interval; aOR, adjusted odds ratio; ASD, autism spectrum disorder; CAH, 17-hydroxyprogesterone; CHS, Center for Health Statistics; CO, free carnitine; CO/(C16 + C18), free carnitine (hexadecanoylcarnitine +octadecanoylcarnitine); C18, octadecanoylcarnitine; C5, isovalerylcarnitine; C8, octanoylcarnitine; C4DC, methylmalonylcarnitineC6DCadipylcarnitine; DSHS, Department of

Autism (or autism spectrum disorder [ASD]) is an often disabling childhood neurologic condition of mostly unknown cause. We previously explored whether there was an association of ASD with any analyte measured in the first newborn screening blood test. Here we explore the second screen. Our matched case–control study examined data on 3–5 year‐old patients with any ASD diagnosis in the Texas Medicaid system in 2010–2012. Subjects were linked to their 2007–2009 newborn screening blood test data, which included values for 36 analytes or analyte ratios. Data were available for 3,005 cases and 6,212 controls. The most compelling associations were evident for fatty acid oxidation analytes octanoylcarnitine (C8) and octanoylcarnitine/acetylcarnitine (C8/C2). Their adjusted odds ratios comparing 10th versus first analyte deciles were between 1.42 and 1.54 in total births, term births, and males. C8 was consistent with first screen results. Adipylcarnitine (C6DC), an organic acid analyte, showed opposite results in the two screens. Several other analytes exhibiting significant associations in the first screen did not in the second. Our results provide evidence that abnormal newborn blood levels of some carnitines may be associated with risk of later ASD, possibly related to their involvement with mitochondrial function in the developing brain.

The purpose of this study was to compare National Immunization Survey (NIS) vaccine coverage rates with Texas Retrospective Immunization Survey (TRIS) vaccine coverage levels. Up-to-date rates for children 19 through 35 months of age as of October 1, 1994, were calculated for single vaccines and two vaccine combinations. The TRIS weighted statewide up-to-date rates for 4-3-1 and 4-3-1-3 were 66 percent and 60 percent, respectively, versus 71 percent and 68 percent for the NIS. Existing retrospective survey procedures can be modified to produce results that may be compared with the NIS.