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.

Twenty-year outcome for individuals with autism and average or near-average cognitive abilities.

Previous studies found substantial variability in adult outcome for people with autism whose cognitive functioning was within the near-average and average ranges. This study examined adult outcome for 41 such individuals (38 men and 3 women) originally identified through an epidemiological survey of autism in Utah. Mean age at the time of their previous cognitive assessment was 7.2 years (SD=4.1, range=3.1-25.9 years) and at follow-up was 32.5 years (SD=5.7 years, range=22.3-46.4 years). Outcome measures included standardized assessments of diagnostic status, cognitive ability, and adaptive behavior. Additional information collected concerned demographic variables, indicators of independence, social relationships, medical and psychiatric conditions, and social service use. Outcomes for this sample were better than outcomes described in previous work on individuals with similar cognitive functioning. For example, half of the participants were rated as "Very Good" or "Good" on a global outcome measure. As in previous studies, there was considerable variability in measured cognitive ability over time. Over half of the sample had large gains or losses of cognitive ability of greater than 1 standard deviation. Cognitive gain was associated with better outcome, as was better adaptive functioning. While all participants had baseline IQs in the nonimpaired range, there was limited evidence to support the use of other early childhood variables to predict adult outcome.

Evidence for linkage on chromosome 3q25-27 in a large autism extended pedigree.

Though autism shows strong evidence for genetic etiology, specific genes have not yet been found. We tested for linkage in a candidate region on chromosome 3q25-27 first identified in Finnish autism families [1]. The peak in this previous study was at D3S3037 (183.9 cM). We tested this region in seven affected family members and 24 of their relatives from a single large extended Utah pedigree of Northern European ancestry. A total of 70 single nucleotide polymorphisms (SNPs) were analyzed from 165 to 204 cM. The maximum NPL-all nonparametric score using SimWalk2snp was 3.53 (empirical p val ue = 0.0003) at 185.2 cM (SNP rs1402229), close to the Finnish peak. A secondary analysis using MCLINK supported this result, with a maximum of 3.92 at 184.6 cM (SNP rs1362645). We tested for alterations in a candidate gene in this region, the fragile X autosomal homolog, FXR1. No variants likely to contribute to autism were found in the coding sequence, exon-intron boundaries, or the promoter region of this gene.

The UCLA-University of Utah epidemiologic survey of autism: Recurrent infections.

Two hundred and forty-one children with autism were ascertained and diagnosed (DSM-III criteria) in an epidemiologic survey of Utah. Pediatric and other pertinent medical records were abstracted for 233 patients and 66 of their siblings without autism for otitis media, upper respiratory, and other infections. A significantly greater number of children with autism had recurrent otitis media, upper respiratory and other infections than their nonautistic siblings. A greater number of children with autisru with recurrent infections had lower IQ scores, seizures, hearing deficits, delayed motor milestones, poorer speech, congenital anomalies, feeding problems, vomiting, diarrhea, and other types of infections than children with autism with mild or no infections. The only significant pre-, peri-, or postnatal risk factors between children with autism with recurrent, mild or no infection was an increase in the maternal-fetal incompatibility (ABO or Rh) in the recurrent infection group. Half the families with more than one child with autism had recurrent infections and 72% of those children with concurrent diseases which effect the CNS had recurrent infections. Methodological limitations are discussed.