The impact of surveillance method and record source on autism prevalence: collaboration with Utah Maternal and Child Health programs.

With the increasing number of Utah children identified with autism spectrum disorders (ASDs), information on the prevalence and characteristics of these children could help Maternal Child Health (MCH) programs develop population building activities focused on prevention, screening, and education. The purpose of this study is to describe Utah's autism registry developed in collaboration with state MCH programs and assess the impact of different record-based surveillance methods on state ASD prevalence rates. The study was conducted using 212 ASD cases identified from a population of 26,217 eight year olds living in one of the three most populous counties in Utah (Davis, Salt Lake, and Utah) in 2002. ASD prevalence was determined using two records based approaches (administrative diagnoses versus abstraction and clinician review) by source of record ascertainment (education, health, and combined). ASD prevalence ranged from 7.5 per 1000 (95% CI 6.4-8.5) to 3.2 per 1000 (95% CI 2.5-3.9) varying significantly (P < .05) based on method and record source. The ratio of male-to-female ranged from 4.7:1 to 6.4:1. No significant differences were found between the two case ascertainment methods on 18 of the 23 case characteristics including median household income, parental education, and mean age of diagnosis. Broad support is needed from both education and health sources as well as collaboration with MCH programs to address the growing health concerns, monitoring, and treatment needs of children and their families impacted by autism spectrum disorders.

Communication disorders: prevalence and comorbid intellectual disability, autism, and emotional/behavioral disorders.

PURPOSE: To determine a population-based estimate of communication disorders (CDs) in children; the co-occurrence of intellectual disability (ID), autism, and emotional/behavioral disorders; and the impact of these conditions on the prevalence of CDs. METHOD: Surveillance targeted 8-year-olds born in 1994 residing in 2002 in the 3 most populous counties in Utah (n = 26,315). A multiple-source record review was conducted at all major health and educational facilities. RESULTS: A total of 1,667 children met the criteria of CD. The prevalence of CD was estimated to be 63.4 per 1,000 8-year-olds (95% confidence interval = 60.4-66.2). The ratio of boys to girls was 1.8:1. Four percent of the CD cases were identified with an ID and 3.7% with autism spectrum disorders (ASD). Adjusting the CD prevalence to exclude ASD and/or ID cases significantly affected the CD prevalence rate. Other frequently co-occurring emotional/behavioral disorders with CD were attention deficit/hyperactivity disorder, anxiety, and conduct disorder. CONCLUSIONS: Findings affirm that CDs and co-occurring mental health conditions are a major educational and public health concern.

Predictors of ascertainment of autism spectrum disorders across nine US communities.

Autism spectrum disorders (ASD) prevalence estimates derived from a single data source under-identify children and provide a biased profile of case characteristics. We analyzed characteristics of 1,919 children with ASD identified by the Autism and Developmental Disabilities Monitoring Network. Cases ascertained only at education sources were compared to those identified at health sources. 38 % were education-only. These were older at their earliest evaluation (54.5 vs. 42.0 months, p < 0.001) and earliest ASD diagnosis (62 vs. 53 months, p < 0.001). More lived in census blocks with lower adult education (p < 0.001). Lower educational attainment of adults in census blocks of residence of education-only cases suggests disparities in access to clinical services with the schools providing crucial services to many families.

Prenatal and perinatal factors associated with intellectual disability.

Prenatal and perinatal risk factors associated with intellectual disability (ID) were studied in 8-year-old Utah children from a 1994 birth cohort (N  =  26,108) using broad ascertainment methods and birth records following the most current recording guidelines. Risk factor analyses were performed inclusive and exclusive of children with a known or suspected underlying genetic disorder. Risk factors identified were poly/oligohydramnios, advanced paternal/maternal age, prematurity, fetal distress, premature rupture of membranes, primary/repeat cesarean sections, low birth weight, assisted ventilation greater than 30 min, small-for-gestational age, low Apgar scores, and congenital infection. Although several risk factors lost significance once children with underlying genetic disorders were excluded, socioeconomic variables were among those that maintained a prominent association with increased ID risk.

Autism spectrum disorder reclassified: a second look at the 1980s Utah/UCLA Autism Epidemiologic Study.

The purpose of the present study was to re-examine diagnostic data from a state-wide autism prevalence study (n = 489) conducted in the 1980s to investigate the impact of broader diagnostic criteria on autism spectrum disorder (ASD) case status. Sixty-four (59 %) of the 108 originally "Diagnosed Not Autistic" met the current ASD case definition. The average IQ estimate in the newly identified group (IQ = 35.58; SD = 23.01) was significantly lower than in the original group (IQ = 56.19 SD = 21.21; t = 5.75; p < .0001). Today's diagnostic criteria applied to participants ascertained in the 1980s identified more cases of autism with intellectual disability. The current analysis puts this historic work into context and highlights differences in ascertainment between epidemiological studies performed decades ago and those of today.

Changes in the administrative prevalence of autism spectrum disorders: contribution of special education and health from 2002-2008.

This study examined changes in the administrative prevalence of autism spectrum disorders (ASD) in Utah children from 2002 to 2008 by record source (school and health), age (four, six, and eight), and special education classification. Prevalence increased 100% with 1 in 77 children aged eight identified with ASD by 2008. Across study years and age groups rates were higher when health and school data were combined with a greater proportion of cases ascertained from health. The proportion of children with both a health ASD diagnosis and a special education autism classification did not significantly change. Most children with an ASD health diagnosis did not have an autism special education classification. Findings highlight the growing health and educational impact of ASD.

Sociodemographic risk factors associated with autism spectrum disorders and intellectual disability.

This study examined the hypotheses that (1) sociodemographic risk factors in young children with autism spectrum disorders (ASD) and/or intellectual disability (ID) significantly vary by disability type, and (2) measures of income (mean adjusted gross income, mean federal taxes paid, and mean tax exemptions) significantly increase between 1994 and 2002, and are lower in families with a child with ASD and/or ID compared with the general population. A multiple source surveillance system utilizing a retrospective record review was used to identify ASD and ID cases from a population of 26,108 eight-year-old children born in 1994 and living in Utah in 2002. ASD without ID (ASD-only, n = 99) cases were significantly more likely to be male (P<0.01) and have mothers of White non-Hispanic ethnicity (P = 0.02). ASD with ID (ASD/ID, n = 33) cases were significantly more likely to be male (P<0.01) and have mothers older than 34 years (P = 0.03). ID without ASD (ID-only, n = 113) cases were significantly more likely to have fathers older than 34 years (P<0.01) and were significantly less likely to have mothers with >13 years education (P<0.01). Measures of income for cases at birth and at 8 years of age were not significantly lower than the general population and mean adjusted income of cases significantly increased from birth to 8 years of age. Investigations focused on defining early sociodemographic risk factors by different endophenotypes of ASD may assist in identifying risk factors for this complex group of neurodevelopmental disorders. Aggregate tax information may be a unique resource to utilize for population-based analysis.

Prenatal, perinatal, and neonatal factors associated with autism spectrum disorders.

OBJECTIVE: To investigate prenatal, perinatal, and neonatal risk factors for autism spectrum disorders by using participants identified through broad ascertainment and reliable classification methods. METHODS: The targeted population was 8-year-old children born in 1994 and residing in 1 of the 3 most populous counties in Utah who were identified as having an autism spectrum disorder on the basis of methodology used by the 2002 Autism and Developmental Disabilities Monitoring Network. Of those identified, 132 children (115 boys, 17 girls) had birth certificate records available. Each child was matched by gender and birth year to 100 controls (11 500 boys, 1700 girls) from the birth certificate database in a nested case-control design. Birth certificate records of participants and controls were surveyed for 23 potentially pathologic prenatal, perinatal, and neonatal factors. RESULTS: The prenatal factors that occurred significantly more frequently among children with autism spectrum disorders were advanced maternal age and parity. Increased duration of education among mothers of children with autism spectrum disorders was small but statistically significant. Significant perinatal factors were breech presentation and primary cesarean delivery. When corrected for breech presentation, a known indication for cesarean delivery, the association between primary cesarean delivery and autism spectrum disorders was eliminated. There were no significant associations found between autism spectrum disorders and neonatal factors. CONCLUSIONS: In the absence of other complications suggesting fetal distress, the association between breech presentation and autism spectrum disorders in this study suggests a shared etiology rather than causal relationship. Additional investigation focused on both genetic and environmental factors that link these autism spectrum disorder risk factors individually or collectively is needed.