Trends in documented co-occurring conditions in children with autism spectrum disorder, 2002-2010

Resting Frontal Gamma Power is Associated with Both Expressive Language and Non-verbal Cognitive Abilities in Young Autistic Children

Previous research links resting frontal gamma power to key developmental outcomes in young neurotypical (NT) children and infants at risk for language impairment. However, it remains unclear whether gamma power is specifically associated with language or with more general cognitive abilities among young children diagnosed with autism spectrum disorder (ASD). The current study evaluates differences in resting frontal gamma power between young autistic and NT children and tests whether gamma power is uniquely associated with individual differences in expressive language, receptive language and non-verbal cognitive abilities in autistic and NT children. Participants included 48 autistic children and 58 age- and sex-matched NT children (ages 22-60 months). Baseline electroencephalography (EEG) recordings were acquired from each participant. Children also completed the Mullen Scales of Early Learning (MSEL). We found that frontal gamma power at rest did not differ between autistic and NT children. Among autistic children, reduced frontal gamma power was significantly associated with both higher expressive language skills and higher non-verbal cognitive skills, controlling for age and sex. The interaction between frontal gamma power and diagnostic status no longer explained unique variance in expressive language skills after controlling for variance associated with non-verbal cognitive skills across autistic and NT children. Together, these findings suggest that reduced gamma power is associated with both better expressive language and non-verbal cognitive skills among young autistic children. Moreover, associations between high frequency neural activity and cognition are not specific to verbal abilities but reflect neural mechanisms associated with general higher-order cognitive abilities in ASD.

Factors Predicting Poor Mental and Physical Health in Parents of Children with Autism Spectrum Disorder: Results from 2016 to 2019 National Survey of Children's Health

Although poor health has been reported in parents of children with autism spectrum disorder (ASD), most studies excluded fathers and focused on mental health. We combined 2016-2019 data from the National Surveys of Children's Health to determine child and parent characteristics that predict poor mental and physical health in fathers (n = 818) and mothers (n = 2111) of children with ASD. For fathers of children with ASD, higher parenting stress was significantly associated with greater odds of poor physical health, whereas racial and ethnic minorities and living at 400% above the federal poverty were significantly associated with lower odds of poor mental health. For mothers of children with ASD, greater child sleep problems were significantly associated with greater odds of poor physical health, and two-parent household living 400% above the poverty line was significantly associated with reported lower odds of poor mental health. Continued efforts to reduce parenting stress and improve child sleep problems, along with expanding existing services and coverages of ASD services, especially for low-income families, may help reduce the burden on these families, preventing adverse future health outcomes in this population.

Distinct Neurodevelopmental Trajectories in Groups of Very Preterm Children Screening Positively for Autism Spectrum Conditions

Very preterm (VPT; < 33 weeks' gestation) toddlers screening positively for autism spectrum conditions (ASC) may display heterogenous neurodevelopmental trajectories. Here we studied neonatal brain volumes and childhood ASC traits evaluated with the Social Responsiveness Scale (SRS-2) in VPT-born toddlers (N = 371; median age 20.17 months) sub-divided into three groups based on their Modified-Checklist for Autism in Toddlers scores. These were: those screening positively failing at least 2 critical items (critical-positive); failing any 3 items, but less than 2 critical items (non-critical-positive); and screening negatively. Critical-positive scorers had smaller neonatal cerebellar volumes compared to non-critical-positive and negative scorers. However, both positive screening groups exhibited higher childhood ASC traits compared to the negative screening group, suggesting distinct aetiological trajectories associated with ASC outcomes.

Maternal risk factors vary between subpopulations of children with autism spectrum disorder

Previous work identified three subgroups of children with ASD based upon co-occurring conditions (COCs) diagnosed during the first 5 years of life. This work examines prenatal risk factors, given by maternal medical claims, for each of the three subgroups: children with a High-Prevalence of COCs, children with mainly developmental delay and seizures (DD/Seizure COCs), and children with a Low-Prevalence of COCs. While some risk factors are shared by all three subgroups, the majority of the factors identified for each subgroup were unique; infections, anti-inflammatory and other complex medications were associated with the High-Prevalence COCs group; immune deregulatory conditions such as asthma and joint disorders were associated with the DD/Seizure COCs group; and overall pregnancy complications were associated with the Low-Prevalence COCs group. Thus, we have found that the previously identified subgroups of children with ASD have distinct associated prenatal risk factors. As such, this work supports subgrouping children with ASD based upon COCs, which may provide a framework for elucidating some of the heterogeneity associated with ASD.

Quantifying the intersection of disability and homelessness in Massachusetts public schools in 2018-2019

BACKGROUND

Homelessness has a major impact on the educational and health trajectories of children. Youth with disabilities may be especially vulnerable to experiencing homelessness, but little epidemiological work has been done to characterize dual disparity. Our goal was to describe the relationship between homelessness and disability among students (age 3-21) receiving public education in Massachusetts in 2018-2019. We evaluated the proportion of students with and without disabilities experiencing homelessness by county and school district.

METHODS

We used publicly available data from the United States and Massachusetts Department's of Education. These data used the McKinney Vento Homelessness Assistance Act definition of homelessness which is a lack of fixed, adequate, and regular housing, and disability was determined by the presence of an individualized education program or individualized family service plan. We calculated percentages of students with and without disabilities experiencing homelessness at the state, county, and district level and calculated and mapped risk of homelessness comparing students and without disability. We also determined the occurrence of disability among those experiencing homelessness.

RESULTS

In Massachusetts public schools, 3.5% of students with disabilities experienced homelessness compared with 2.4% of students without disabilities (relative risk 1.50, 95% CI: 1.47, 1.53). A greater proportion of students with disabilities experienced homelessness compared with students without disabilities in all counties. In sum, 24.8% of students experiencing homelessness had a reported disability.

CONCLUSIONS

In Massachusetts public schools, a greater proportion of students with disabilities experience homelessness compared with students without disabilities, and disability is common among students experiencing homelessness. We hypothesize potential mechanisms, such as the financial cost of disability, that may lead to this finding. Findings support the need for additional funding and interventions for school districts and communities to better serve vulnerable students with disabilities experiencing homelessness.

Fertility rates in women with intellectual and developmental disabilities in Wisconsin Medicaid

BACKGROUND

Women with intellectual and developmental disabilities (IDD) face stigma and inequity surrounding opportunity and care during pregnancy. Little work has quantified fertility rates among women with IDD which prevents proper allocation of care.

OBJECTIVE

Our objective was to cross-sectionally describe fertility patterns among women with and without intellectual and developmental disabilities (IDD) in 10-years of Medicaid-linked birth records.

STUDY DESIGN

Our sample was Medicaid-enrolled women with live births in Wisconsin from 2007 to 2016. We identified IDD through prepregnancy Medicaid claims. We calculated general fertility-, age-specific-, and the total fertility-rates and 95% confidence intervals (95% CI) for women with and without IDD and generated estimates by year and IDD-type.

RESULTS

General fertility rate in women with IDD was 62.1 births per 1000 women with IDD (95% CI 59.2, 64.9 per 1000 women) and 77.1 per 1000 for women without IDD (95% CI: 76.8, 77.4 per 1000 women). General fertility rate ratio was 0.81 (95% CI: 0.7, 0.9). Total fertility was 1.80 births per woman with IDD and 2.05 births per woman without IDD (rate ratio: 0.89 95% CI: 0.5, 1.5). Peak fertility occurred later for autistic women (30-34 years), compared with women with other IDD (20-24 years).

CONCLUSION

In Wisconsin Medicaid, general fertility rate of women with IDD was lower than women without IDD: the difference was attenuated when accounting for differing age distributions. Results highlight the disparities women with IDD face and the importance of allocating pregnancy care within Medicaid.

Food insecurity in households of children with ASD in COVID-19 pandemic: A comparative analysis with the Household Pulse Survey Data using stabilized inverse probability treatment weights

Background

Before the COVID-19 pandemic, households of children on the autism spectrum were more likely to be food insecure than households of children without disabilities. With the unprecedented social, public health, and economic disruption caused by the pandemic, food insecurity has likely increased among families of children on the autism spectrum.

Objective

This analysis aims to compare the prevalence of food insecurity between the Autism Speaks' Food Insecurity Survey (ASFIS) administered during the Fall of 2020 and a nationally representative sample from the Household Pulse Survey (HPS) data collected during a similar timeframe.

Methods

A propensity score analysis was utilized to create stabilized inverse probability treatment weights for adjusting background differences between the two groups. A logistic regression model was computed to estimate the odds of food insecurity in the ASFIS participants compared with those in the HPS data.

Results

After adjusting for background differences, households of children on the autism spectrum in the ASFIS were about four times more likely to be food insecure than households in the general population contained in the HPS data (OR = 3.7; 95% CI: 3.1–4.4).

Conclusions

The breakdown of social and economic supports during the COVID-19 pandemic contributed to a significantly higher likelihood of food insecurity among families of children on the autism spectrum.

Population-Based Psychiatric Comorbidity in Children and Adolescents With Autism Spectrum Disorder: A Meta-Analysis

Psychiatric comorbidity in autism spectrum disorder (ASD) is a subject of critical scientific importance, affecting the quality of life, prognosis, and functional outcomes. The prevalence of psychiatric disorders vary considerably according to variables such as index subject characteristics, study setting, sampling frame, diagnostic methods used, as well as country of geographic origin. To date, most studies comprise clinical or treatment referral samples in tertiary care or subjects enrolled in clinical trials and genetic cohort collections. Such samples carry the potential for overestimation of both the frequency and severity of psychiatric comorbidity. A systematic literature search was performed using PubMed and Web of Science databases restricted to population-based study publications in the English between May 1, 2015, and May 31, 2020. A comprehensive keyword list was generated to investigate co-occurrence of psychiatric disorders in children and adolescents with ASD. A wide range of DSM-5 based disorders such as anxiety, mood, ADHD, intellectual disability/intellectual developmental disorder, eating/feeding, gender dysphoria and sleep-wake disorders were assessed. Initial search revealed a total of 1674 articles after removal of duplicates. Two independent researchers conducted a parallel-blinded screening process to identify the eligible studies based on titles and abstracts; 39 studies were analyzed in the current review. The main findings show prevalence estimates of 22.9% (95% CI: 17.7- 29.2) for intellectual disability; 26.2% (22-31) for attention-deficit hyperactivity disorder; 11.1% (8.6-14.1) for anxiety disorders; 19.7% (11.9-30.7) for sleep disorders; 7% (5.2- 9.3) for disruptive disorders; 2% (1.3- 3.1) for bipolar disorders; 2.7% (1.8- 4.2) for depression; 1.8% (0.4-8.7) for obsessive-compulsive disorder; and 0.6% (0.3-1.1) for psychosis. Psychiatric comorbidity in population-based studies is lower than in clinical and referred samples. However, our results also indicate that the frequency of psychiatric comorbidity in children and adolescents with ASD in the population context is considerable, without the influence of referral bias implicit in clinical and treatment samples. There is a need for better targeted diagnostic tools to detect psychiatric comorbidity in children and youth in future population-based studies, as an essential component in providing care as well as new insights into the nature and mechanisms of its underlying associations.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/prospero/], identifier [CRD42021234464].

Correlates of obesity in adolescents with and without autism spectrum disorder: The 2017-2018 National Survey of Children's Health

BACKGROUND

The prevalence of autism spectrum disorder (ASD) and childhood obesity are increasing, and youth with ASD are at an increased risk of obesity compared to typically developing youth. Specific obesity risk factors in adolescents with ASD remain poorly understood.

OBJECTIVE

This study examined correlates of obesity among adolescents with and without ASD using extant 2017-2018 National Survey of Children's Health (NSCH) data.

METHODS

This cross-sectional study examined the co-occurrence of obesity among US adolescents with ASD aged 10-17 years compared to those without ASD, adjusting for sociodemographic characteristics, co-occurring conditions, and relevant covariates, using 2017-2018 NSCH data. Multiple logistic regression was used to compare the odds of obesity among children with mild ASD, moderate/severe ASD, and without ASD.

RESULTS

Odds of obesity were higher in adolescents with ASD compared to adolescents without ASD (cOR 1.9, CI 1.3-2.7). In the adjusted model, the odds of obesity were not significantly higher in those with mild or moderate/severe ASD compared to those without ASD. Odds of obesity were higher for all adolescents who were Hispanic or Black, as well as those with lower household income or with one or more co-occurring conditions.

CONCLUSIONS

The association between obesity and ASD in this study highlights the need for greater attention to nutrition, physical activity, and co-occurring conditions among adolescents with ASD. Effective interventions to curtail the risks among racial/ethnic minority adolescents and adolescents with lower household income are needed. Further research is needed to examine additional factors associated with obesity in adolescents with ASD, including family, community, organizational, and policy factors.

Medication Use in the Management of Comorbidities Among Individuals With Autism Spectrum Disorder From a Large Nationwide Insurance Database

IMPORTANCE

Although there is no pharmacological treatment for autism spectrum disorder (ASD) itself, behavioral and pharmacological therapies have been used to address its symptoms and common comorbidities. A better understanding of the medications used to manage comorbid conditions in this growing population is critical; however, most previous efforts have been limited in size, duration, and lack of broad representation.

OBJECTIVE

To use a nationally representative database to uncover trends in the prevalence of co-occurring conditions and medication use in the management of symptoms and comorbidities over time among US individuals with ASD.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective, population-based cohort study mined a nationwide, managed health plan claims database containing more than 86 million unique members. Data from January 1, 2014, to December 31, 2019, were used to analyze prescription frequency and diagnoses of comorbidities. A total of 26 722 individuals with ASD who had been prescribed at least 1 of 24 medications most commonly prescribed to treat ASD symptoms or comorbidities during the 6-year study period were included in the analysis.

EXPOSURES

Diagnosis codes for ASD based on International Classification of Diseases, Ninth Revision, and International Statistical Classification of Diseases and Related Health Problems, Tenth Revision.

MAIN OUTCOMES AND MEASURES

Quantitative estimates of prescription frequency for the 24 most commonly prescribed medications among the study cohort and the most common comorbidities associated with each medication in this population.

RESULTS

Among the 26 722 individuals with ASD included in the analysis (77.7% male; mean [SD] age, 14.45 [9.40] years), polypharmacy was common, ranging from 28.6% to 31.5%. Individuals' prescription regimens changed frequently within medication classes, rather than between classes. The prescription frequency of a specific medication varied considerably, depending on the coexisting diagnosis of a given comorbidity. Of the 24 medications assessed, 15 were associated with at least a 15% prevalence of a mood disorder, and 11 were associated with at least a 15% prevalence of attention-deficit/hyperactivity disorder. For patients taking antipsychotics, the 2 most common comorbidities were combined type attention-deficit/hyperactivity disorder (11.6%-17.8%) and anxiety disorder (13.1%-30.1%).

CONCLUSIONS AND RELEVANCE

This study demonstrated considerable variability and transiency in the use of prescription medications by US clinicians to manage symptoms and comorbidities associated with ASD. These findings support the importance of early and ongoing surveillance of patients with ASD and co-occurring conditions and offer clinicians insight on the targeted therapies most commonly used to manage co-occurring conditions. Future research and policy efforts are critical to assess the extent to which pharmacological management of comorbidities affects quality of life and functioning in patients with ASD while continuing to optimize clinical guidelines, to ensure effective care for this growing population.

Resources, Problems and Challenges of Autism Spectrum Disorder Diagnosis and Support System in Poland

The article refers to resources, problems and challenges of autism diagnosis and support system in Poland. The resources include: the increasing number of specialists, diagnostic and therapeutic centres, well-established course of education for people working with youths, standardised and normalised diagnostic tools. The diagnostic process is not without some areas in need of our focus: the tendency of some specialists to make unauthorised diagnosis, overshadowing; underestimation of comorbidity of ASD with other disorders. The challenges refer to introducing an effective system of monitoring the services provided in form of certification and control in order to prevent their abuse, initiating category of temporary diagnosis; paying more attention on individual's resources, better cooperation among specialists, teachers and families, developing and unifying diagnostic standards.

Healthcare utilization among children with early autism diagnoses, children with other developmental delays and a comparison group

Aim: To describe healthcare utilization patterns among children with autism (n = 1821), and compare these patterns to children with other developmental delays (DD; n = 12,336) and a population comparison (PC; n = 18,210) cohort. Materials & methods: Retrospective study of administrative billing data. Results: Children with autism had roughly six-times more annual outpatient visits as PC children and twice as many as children with DD. Children with autism were more likely than PC children to use nearly all services, but comparisons between the autism and DD cohorts were mixed. Children with autism were more likely to have psychiatry/psychology visits, 'other' specialty care visits and psychotropic prescriptions, but less likely to have pediatric specialty care visits, immunizations and some prescriptions. Conclusion: Findings reveal opportunities to streamline, coordinate or improve care for young children with autism, particularly for outpatient services, and to give caregivers appropriate anticipatory guidance about what to expect after an autism diagnosis.

California Autism Prevalence by County and Race/Ethnicity: Declining Trends Among Wealthy Whites

County-level ASD prevalence was estimated using an age-resolved snapshot from the California Department of Developmental Services (DDS) for birth years 1993–2013. ASD prevalence increased among all children across birth years 1993–2000 but plateaued or declined thereafter among whites from wealthy counties. In contrast, ASD rates increased continuously across 1993–2013 among whites from lower income counties and Hispanics from all counties. Both white ASD prevalence and rate of change in prevalence were inversely correlated to county income from birth year 2000–2013 but not 1993–2000. These disparate trends within the dataset suggest that wealthy white parents, starting around 2000, may have begun opting out of DDS in favor of private care and/or making changes that effectively lowered their children’s risk of ASD.

Physical health of autistic girls and women: a scoping review

BACKGROUND

There is a growing recognition of sex and gender influences in autism. Increasingly, studies include comparisons between sexes or genders, but few have focused on clarifying the characteristics of autistic girls'/women's physical health.

METHODS

A scoping review was conducted to determine what is currently known about the physical health of autistic girls/women. We screened 1112 unique articles, with 40 studies meeting the inclusion criteria. We used a convergent iterative process to synthesize this content into broad thematic areas.

RESULTS

Autistic girls/women experience more overall physical health challenges compared to non-autistic girls/women and to autistic boys/men. Emerging evidence suggests increased prevalence of epilepsy in autistic girls/women compared to non-autistic girls/women and to autistic boys/men. The literature also suggests increased endocrine and reproductive health conditions in autistic girls/women compared to non-autistic girls/women. Findings regarding gastrointestinal, metabolic, nutritional, and immune-related conditions are preliminary and inconsistent.

LIMITATIONS

The literature has substantial heterogeneity in how physical health conditions were assessed and reported. Further, our explicit focus on physical health may have constrained the ability to examine interactions between mental and physical health. The widely differing research aims and methodologies make it difficult to reach definitive conclusions. Nevertheless, in keeping with the goals of a scoping review, we were able to identify key themes to guide future research.

CONCLUSIONS

The emerging literature suggests that autistic girls/women have heightened rates of physical health challenges compared to non-autistic girls/women and to autistic boys/men. Clinicians should seek to provide holistic care that includes a focus on physical health and develop a women's health lens when providing clinical care to autistic girls/women.

Wandering Among Preschool Children with and Without Autism Spectrum Disorder

OBJECTIVES

(1) Report the occurrence of wandering, or leaving a supervised space, among children with confirmed autism spectrum disorder (ASD), other developmental delay (DD) with a previous but unconfirmed ASD diagnosis (DDprevASD), DD without a previous ASD diagnosis, and a population comparison group (POP) at an age when wandering is no longer expected and (2) explore whether ASD status is associated with wandering independent of behavioral, developmental, and maternal factors.

METHOD

Parents and children aged 4 to 5 years enrolled in the Study to Explore Early Development Phase-1+2. All children were screened for ASD symptoms upon enrollment. Those with ASD symptoms and/or a previous ASD diagnosis received the Mullen Scales of Early Learning (MSEL) to determine their developmental level and 2 ASD diagnostic tests to determine their ASD status. All other children were evaluated with the MSEL alone. Mothers completed the Child Behavior Checklist/1½-5, which includes an item on whether the child wanders away (categorized as at least sometimes true vs not true) and items assessing behavior problems.

RESULTS

Children with ASD (N = 1195) were significantly more likely to wander than children classified as DDprevASD (N = 230), DD (N = 1199), or POP (N = 1272) (60.4%, 41.3%, 22.3%, and 12.4%, respectively, p < 0.01). ASD status, very low developmental level, and affective, anxiety, attention, and oppositional problems were each independently associated with wandering behavior.

CONCLUSION

Wandering is significantly more common among children with ASD and those with behavioral and developmental problems compared with other children. These findings can be used to increase the awareness of wandering among children with atypical development.

Is the Autism Boom Headed for Medicaid? Patterns in the Enrollment of Autistic Adults in Wisconsin Medicaid, 2008-2018

Our primary objective was to describe demographic characteristics and enrollment patterns in a unique 11-year full sample of adult Wisconsin Medicaid beneficiaries with identified autism spectrum disorder (ASD) or intellectual disability (ID). We obtained de-identified Medicaid claims data for adults with a recorded ASD or ID diagnosis aged 21 and older with any Medicaid fee-for-service claims between January 1, 2008 and December 31, 2018. We assessed enrollment, age, number of visits, and paid amount per year using generalized linear models with a random intercept for each beneficiary. We identified claims for 4,775 autistic adults without ID, 2,738 autistic adults with ID, 14,945 adults with ID, and 3,484 adults with Down syndrome. The age distribution of the diagnostic group with ASD diagnoses was right skewed with a majority of beneficiaries less than age 30. The ASD without ID diagnostic group had the least visits and paid amount per person per year compared to other groups. In each age category, the ASD with ID diagnostic group had the most paid amount per person per year compared to other groups. It is urgent that we identify the health and health service needs of autistic adults from young adulthood through old age. Our findings have implications for ensuring adequate health coverage across the lifespan and highlight the importance of a strong and accessible health care system for autistic people. Autism Res 2019, 12: 1541-1550. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Medicaid provides health insurance to disabled people who meet income requirements. We assessed patterns of enrollment and service use among autistic adults and adults with developmental disabilities in Wisconsin Medicaid. We found a consistent influx of new young autistic adults without intellectual disability into the Medicaid system, with fewer visits and lower paid amounts compared to other developmental disability groups. The changing population of autistic people using Medicaid has implications for providing health care to autistic adults in the future.

The Physical and Mental Health of Middle Aged and Older Adults on the Autism Spectrum and the Impact of Intellectual Disability

BACKGROUND

People on the autism spectrum may have more physical and mental health conditions in midlife and old age compared to the general population. This study describes the physical and mental health of a unique sample of all middle aged and older Wisconsin Medicaid beneficiaries with an autism spectrum disorder diagnosis and tests differences between those with and without co-occurring intellectual disability.

METHOD

Using de-identified Medicaid claims data for 143 adults with a recorded autism spectrum disorder diagnosis aged 40-88 years with any Wisconsin Medicaid claims in 2012 through 2015, we extracted diagnoses for physical and mental health conditions from fee-for-service claims. Logistic regression analyses-controlling for sex, race, and age-compared the adjusted odds of physical and mental health conditions for those with and without intellectual disability.

RESULTS

Many physical and mental health conditions, including immune conditions (70.6%), cardiovascular disease (49.0%) and its risk factors (46.2%), sleep disorders (85.3%), gastrointestinal disorders (49.7%), neurologic conditions (55.9%), and psychiatric disorders (72.0%) were highly prevalent in our full sample. Although there were many similarities between those individuals with and without co-occurring intellectual disability, middle aged and older adults on the autism spectrum had higher prevalence of epilepsy and lower prevalence of depression and anxiety compared to those without co-occurring intellectual disability.

CONCLUSIONS

Findings suggest that people on the autism spectrum have a high prevalence of physical and mental health conditions in midlife and old age, regardless of intellectual disability status.

Clustering of co-occurring conditions in autism spectrum disorder during early childhood: A retrospective analysis of medical claims data

Individuals with autism spectrum disorder (ASD) are frequently affected by co-occurring medical conditions (COCs), which vary in severity, age of onset, and pathophysiological characteristics. The presence of COCs contributes to significant heterogeneity in the clinical presentation of ASD between individuals and a better understanding of COCs may offer greater insight into the etiology of ASD in specific subgroups while also providing guidance for diagnostic and treatment protocols. This study retrospectively analyzed medical claims data from a private United States health plan between years 2000 and 2015 to investigate patterns of COC diagnoses in a cohort of 3,278 children with ASD throughout their first 5 years of enrollment compared to 279,693 children from the general population without ASD diagnoses (POP cohort). Three subgroups of children with ASD were identified by k-means clustering using these COC patterns. The first cluster was characterized by generally high rates of COC diagnosis and comprised 23.7% (n = 776) of the cohort. Diagnoses of developmental delays were dominant in the second cluster containing 26.5% (n = 870) of the cohort. Children in the third cluster, making up 49.8% (n = 1,632) of the cohort, had the lowest rates of COC diagnosis, which were slightly higher than rates observed in the POP cohort. A secondary analysis using these data found that gastrointestinal and immune disorders showed similar longitudinal patterns of prevalence, as did seizure and sleep disorders. These findings may help to better inform the development of diagnostic workup and treatment protocols for COCs in children with ASD. Autism Res 2019, 12: 1272-1285. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Medical conditions that co-occur with autism spectrum disorder (ASD) vary significantly from person to person. This study analyzed patterns in diagnosis of co-occurring conditions from medical claims data and observed three subtypes of children with ASD. These results may aid with screening for co-occurring conditions in children with ASD and with understanding ASD subtypes.