Neurodevelopmental and Mental Health Outcomes in a National Clinical Sample of Youth With Sex Chromosome Trisomies Compared With Matched Controls.

The study used billing and problem list diagnoses from electronic health records, so diagnoses managed outside the network, including community or school services, may not have been captured. It could not confirm DSM-5 criteria, genotype, mosaicism, or the reason genetic testing was done. Cases were children who already had a clinical diagnosis of sex chromosome trisomy in childhood, which is a minority of people with these conditions and may overrepresent those with health concerns. Participants were seen at tertiary pediatric centers, so both cases and controls may have more complex concerns than the general population. Cases had more outpatient encounters than controls, which may affect how many diagnoses were recorded. Rare diagnoses were not reportable when counts were too small under data restrictions. The study could not tell whether differences between XXY, XYY, and XXX groups reflect true phenotype differences or differences in how the conditions were diagnosed. The analysis compared groups using existing records and cannot show that sex chromosome trisomy caused the diagnoses or that therapy use improved outcomes.

The authors disclosed no known conflicts of interest. The study used deidentified electronic health record data from PEDSnet and was approved by the PEDSnet Data Coordinating Center.

Do not read the higher diagnosis and therapy rates as proof that sex chromosome trisomies cause these outcomes or that therapy use improves them. The study compared existing billing records and did not test treatments.