Brief Report: Associations Between Self-injurious Behaviors and Abdominal Pain Among Individuals with ASD-Associated Disruptive Mutations.

The sample was small, and complete data were not available for all measures. The self-injury status model included 83 participants, the severity model included 97, and the model that excluded possible or mild self-injury included 75, not all 112. Gene groups were small, so the lack of differences across mutation groups may be due to small sample sizes rather than true absence of differences. Severe abdominal pain was coded from caregiver report of a past or current diagnosis by a medical professional using a single item, so milder or undiagnosed pain may have been missed. Only 18% of the sample had reported severe abdominal pain, lower than community reports, and this may reflect underrecognition in people with intellectual disability; 88.4% of the sample had intellectual disability. Participants with possible or mild self-injury on the ADI-R were excluded from main analyses, so the results may not apply to unclear or mild cases. The self-injury measures did not provide detailed information about function, exact topography, or clinical course.

One author is on the Scientific Advisory Board of DNAnexus, Inc. The remaining authors have no conflicts of interest to report.

Do not read the 8.08 times likelihood as proof that abdominal pain causes self-injury. The study found associations in a small cohort, and the primary comparison across mutation groups showed no significant differences in self-injury or severe abdominal pain rates.