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Background: Up to 19% of patients with Down syndrome (DS) meet diagnostic criteria for autism spectrum disorder (ASD) (Channell, et al, 2019). While the medical and psychological comorbidities for patients with DS or ASD are well characterized, outcomes for patients with a dual diagnosis (DS-ASD) are poorly understood. Large DS-ASD cohorts and comparison samples are needed to fill this gap, as well as methods for grouping and analyzing complex diagnostic phenotypes. Objective: Our objective is to utilize Cerner Health Facts, a multi-institutional healthcare database, to identify large populations with DS, ASD, and DS-ASD, allowing for characterization and comparison of their ICD9/10 diagnoses. A secondary objective is the development of a higher order classification system based on ICD9/10 diagnoses to allow for identification of meaningful differences in body system dysfunction across populations. Design/Methods: Patients birth to 18 years with at least one encounter in Cerner Health Facts and diagnoses of ASD, DS, or both were identified. Medical and psychological diagnoses in the form of ICD9/10 codes were extracted and combined into phenotype codes (Denny, et al, 2013). Phenotype codes were then grouped by physiologic system into compound phenotypes. Prevalence rates for these compound phenotypes were then computed and compared across the DS, ASD, and DS-ASD samples. Results: 1,087 patients with DS-ASD, 22,862 patients with DS, and 98,979 patients with ASD were identified. Thirty-three compound phecode groupings were developed from 1,886 phecodes. As an example, 47.9% of DS-ASD patients were noted to have diagnoses in the Pulmonology/Sleep grouping, similar to those with DS. However, Pulmonology/Sleep diagnoses were over three times more prevalent compared to those with ASD. In the DS-ASD population, Neurologic/Musculoskeletal diagnoses were nearly 2.5 times more prevalent compared to those with DS, and over 1.75 times more prevalent when compared to those with ASD. Conclusion(s): Patients with DS-ASD had higher rates of a wide range of medical and psychological diagnoses compared to those with DS or ASD alone. The compound phenotype classification scheme is a viable method for comparing diagnoses between distinct populations, as well as aggregating differences to produce interpretable phenotypic trends. These trends can both inform clinical practice and provide the basis for future work, such as investigating the link between mortality and comorbidities in those with DS-ASD.

Presented at the 2021 PAS Virtual Conference

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Behavioral Medicine | Gastroenterology | Pediatrics

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Presented at the 2021 PAS Virtual Conference

Characterization of Comorbidities in Patients with a Dual Diagnosis of Down Syndrome and Autism Spectrum Disorder Using Cerner Health Facts