ARFID at the intersection of eating, anxiety, and neurodevelopmental disorders
Although defined as a feeding and eating disorder, ARFID has many similarities to neurodevelopmental disorders (NDDs), such as the early onset, the stability throughout life, and the high heritability. In a recent (not yet published) twin study, we found that ARFID has a very high heritability (ca. 80%), which is comparable to the heritability of autism and ADHD. ARFID and NDDs also often co-occur. In the Japanese sample we found that children with early neurodevelopmental problems—especially problems with communication and language, social interaction, attention, concentration, and sleep—were more likely to screen positive for ARFID between age 4-7.2 In another study where we examined ARFID in children from a low-resource, multiethnic area who were diagnosed with autism before the age of 6, we found that 28% of these children had ARFID, and many more had feeding problems that didn’t meet criteria in ARFID (only 24% had no feeding problems at all).3 However, ARFID is also closely associated with anxiety disorders. For example, the fear-based presentation of ARFID could also be considered as a specific phobia (of food). Furthermore, comorbidity with anxiety disorders in people with ARFID is very high: about 35-72% have diagnosed anxiety disorders; most common are generalized anxiety disorder and social anxiety.