BACKGROUND: In pediatric settings, parents often raise concerns about possible gastrointestinal (GI) symptoms in autism spectrum disorder (ASD), yet the specificity of these concerns are not well studied. OBJECTIVE: To conduct a meta-analysis of research investigating GI symptoms among children with ASD. METHODS: We searched Medline, PsycINFO, and PubMed databases (1980–2012) in peer-reviewed journals. Analysis involved studies with a comparison group presenting quantitative data on GI symptoms using combinations of terms for ASD and GI indicators. The systematic search yielded 15 studies. We calculated effect sizes and 95% confidence intervals (CIs) using a random-effects model. RESULTS: Children with ASD experience significantly more general GI symptoms than comparison groups, with a standardized mean difference of 0.82 (0.24) and a corresponding odds ratio (OR) of 4.42 (95% CI, 1.90–10.28). Analysis also indicated higher rates of diarrhea (OR, 3.63; 95% CI, 1.82–7.23), constipation (OR, 3.86; 95% CI, 2.23–6.71), and abdominal pain (OR, 2.45; 95% CI, 1.19–5.07). CONCLUSIONS: Results indicate greater prevalence of GI symptoms among children with ASD compared with control children. Identified studies involved high methodological variability and lack of comprehensive data prohibited analysis of GI pathophysiologies (eg, gastroesophageal reflux) typically associated with organic etiologies, limiting conclusions about the underpinnings of the observed association. Future research must address critical questions about the causes and long-term impact of GI symptoms in ASD. Such analyses will require more systematic research and clinical activities, including improved diagnostic screening, standardized assessment, and exploration of potential moderators (eg, dietary restrictions).

Feeding problems represent a frequent concern reported by caregivers of children with autism spectrum disorders, and growing evidence suggests atypical patterns of intake may place this population at risk of nutritional and/or related medical issues, including chronic vitamin and mineral deficiencies, poor bone growth, and obesity. This combination of factors emphasizes a clear need to identify and disseminate evidence-based treatment of feeding problems associated with autism spectrum disorders. Behavioral intervention represents an effective treatment for chronic feeding concerns in this population; however, evidence has largely been established with trained therapists working in highly structured settings. This pilot study seeks to fill this gap in the literature by describing and evaluating the Autism MEAL Plan, a behaviorally based parent-training curriculum to address feeding problems associated with autism spectrum disorders. We assessed the feasibility of the intervention in terms of program content and study protocol (e.g. recruitment and retention of participants, assessment procedures), as well as efficacy in terms of changes in feeding behaviors. A total of 10 families participated in the treatment condition, and the program was evaluated using a waitlist control design (n = 9), representing the first randomized-control study of a feeding intervention in autism spectrum disorders. Results provide provisional support regarding the utility of the program, including high social validity, parent perception of effectiveness, and reduced levels of caregiver stress following intervention. Implications, limitations, and future directions for this line of research are discussed.