Nutritional Deficiency Disease Secondary to ARFID Symptoms Associated with Autism and the Broad Autism Phenotype: A Qualitative Systematic Review of Case Reports and Case Series.

Background: The demographics, weight statuses, and dietary patterns of people with autism or the broad autism phenotype who experience a severe nutrient deficiency disease due to symptoms of avoidant/restrictive food intake disorder have not been well established.

Objective: The primary objective of this review was to examine the relationship between the demographics, weight statuses, dietary patterns, and nutrient deficiency diseases that characterize the most severe manifestations of avoidant/restrictive food intake disorder symptomology associated with autism or the broad autism phenotype.

Methods: A systematic review of English and non-English articles published up to August 29, 2019, on the Scopus, PubMed, and Cumulative Index to Nursing and Allied Health Literature Plus electronic databases was conducted. Additional cases were identified through the reference list of all included articles. The search terms used were "autis AND (deficiency OR scurvy)". Only case reports or case series in which a person of any age who had been identified as having a formal diagnosis of autism or autism symptoms and a disease of nutritional deficiency due to self-imposed dietary restrictions were included. Data were independently extracted by 8 authors using predefined data fields.

Results: A total of 76 cases (patients were aged 2.5 to 17 years) from 63 articles that were published from 1993 through 2019 were found. More than 85% cases (65 of 76 patients) were from articles published in the past 10 years. The largest percentage of published cases (69.7% [53 of 76]) involved scurvy, a vitamin C deficiency. The second-largest percentage of published cases (17.1% [13 of 76]) involved eye disorders secondary to vitamin A deficiency. Other primary nutrient deficiencies reported were thiamin, vitamin B-12, and vitamin D. In 62.9% (22 of 35) of the patients for which a body mass index or a weight percentile for age was provided, the patient was within normal weight parameters, per Centers for Disease Control weight status categories.

Conclusions: Based on the 63 articles extracted for this systematic review, nutritional deficiency diseases related to inadequate intakes of vitamin A, thiamin, vitamin B-12, vitamin C, and vitamin D were found in individuals with autism and the broad autism phenotype who had severe self-imposed dietary restrictions. When weight information was provided, most of the youth in these cases were not reported to be underweight. Individuals of any weight who present with symptoms of avoidant/restrictive food intake disorder can benefit from early and frequent screening for adequacy of micronutrient intake, regardless of whether they have a clinical diagnosis of autism.