Sensory Processing, Gastrointestinal Symptoms and Parental Feeding Practices in The Explanation of Food Selectivity: Clustering Children with and Without Autism

Children with Autism Spectrum Disorders are a group of neurodevelopmental disorders (ASD) and compared to Typically Developing Children (TDC), experience significantly more feeding problems. Food selectivity is a complex phenomenon that involves individual and contextual factors (sensory abnormalities, severity of behavioral problems, gastrointestinal disorders, parenting styles and so on). The clarification of these key factors is the aim of the current study, comparing a group of children with ASD with a group of TDC on different variables such as food selectivity, anthropometric measures, gastrointestinal symptoms, diet, sensory processing and caregiver feeding practices. Moreover, the same variables described above are studied using a classification model for both groups. Results display that parenting style, sensory anomalies and gastrointestinal symptoms were associated with food refusal of children. Moreover, it is possible to observe similar profiles in children with feeding problems in both groups. Autism Spectrum Disorders (ASD) are a group of neurodevelopmental disorders characterized by social communication deficit and a tendency to engage in a pattern of restricted and repetitive behaviors, in which sensory issues are included (American Psychiatric Association [APA], [1]). Children with ASD, compared to Typically Developing Children (TDC), experience significantly more feeding problems [2], with food selectivity being the most frequently reported. Food selectivity could be operationally defined on the basis of the occurrence of the following behaviours: food refusal, limited repertoires of food, high frequency single food intake [3]. Several research studies observed a prevalence between 70% and 80% of food selectivity among children with ASD [4-6], despite parents never having described their children as in appetent [7]. Klein and Nowak (1999) [8] found that 53% of children were reluctant to try new foods. Whiteley, Rodgers, and Shattok (2000) [9] indicated a prevalence of 83% of children with a restricted repertoire of foods eaten. Similarly, Schreck and Williams (2006) [6] found that 57% of children refused food, while 72% accepted limited variety. A more consistent prevalence was found by Lockner, Crowe, and Skipper (2008), [10] who thought that new foods refusal in children with ASD was higher compared to TDC (95% vs. 47%). Furthermore, children with ASD were characterized also by a limited variety of food intake (16% vs. 58%). However, Bandini et al. (2010) [3] found lower rates of refusal in both groups compared to previous studies (41.7% vs. 18.9%). Methodological differences in research studies such as different approach mechanisms may have accounted for conflicting results. Food selectivity in ASD is really important because it is linked to health risks for children, and it may require some medical intervention [11]. In fact, in a recent review by the same authors, BMI and other anthropometric values in children with autism seem to differ from that of TDC, along with nutritional insufficiency [12]. However, in this survey as well as other recent studies [13,14] this difference was not always confirmed, with the literature still seeming incomplete. At the same time several studies tried to identify some of the causes for food selectivity in children with ASD. Some researchers investigated the role of motor coordination disorders and/or gastrointestinal problems. Children with praxis difficulties may lack the necessary motor skills to adequately handle food, leading to negative emotions avoidance [15]. Also, researchers have found contrasting results in Gastrointestinal Disorders (GID). According to a recent survey, a higher frequency of GID may be associated with a more severe food selectivity in children with ASD [16], while for others, the two phenomena seem largely independent in children with autism [17]. Indeed, children with and without autism experiencing frequently bowel problems and/or gastroesophageal reflux could display more feeding-related problems, since they could try to avoid foods associated with adverse circumstances. On the other hand, many children with autism commonly well-defined as picky or choosy eaters do not show gastrointestinal issues. In fact, other authors explained food selectivity in children with ASD as a consequence of repetitive behaviour and restricted interests [18,19]. However, the most accepted etiological hypothesis would seem to postulate a relationship between sensory perception abnormalities and rejection of food [20] both from children with typical and atypical development. As shown by Nadon, Feldman, Dunn, and Gisel (2011) [21], almost 90% of children with ASD show impairment in sensory processing information, including a hypo and or hypersensitivity to environmental stimuli. The differences in sensory processing in children with ASD have been well documented [22]. These abnormalities have been associated with both behavioural and emotional problems [23,24] and the severity of symptoms [25]. Since foods have several properties which can stimulate sense organs, it is possible that children who have sensory perception alteration might refuse them to a greater extent as they are more or less stimulating. From interviews with parents and behavioural observations it has been proven that children with ASD are adverse towards food characteristics such as texture, smell, taste and temperature [10,14,23,26-28], yet other food properties seem to be more important to them such as brand, packaging (patterns/colours), food presentation and even cutlery [4,6,9]. Finally, eating behaviours not only have a biological matrix but are also influenced by social and cultural variables [29], therefore it’s possible that in addition to the individual dimensions, parental feeding practices can also play a significant role in food selectivity. Currently, a research study [13] evaluated the parental feeding style and the food selectivity in children with ASD, indicating strategies as prompting/encouragement as the most used among parents. This direction of research is of particular interest not only scientifically but also in the way of application. If a relationship between parental feeding practices and food selectivity is found, it will be possible to devise intervention programs aimed at promoting functional parenting styles in order to achieve healthy eating behaviors. Hence, the aim of the current study is to compare a group of children with ASD with a group of TDC on different variables such as food selectivity, weight, gastrointestinal disorders, diet, sensory process and caregiver feeding practices. To sum up, we want to explore the following research questions: a) if the group of children with ASD shows more levels of food selectivity than controls; b) if the children with ASD report lower scores of BMI than controls; c) if the clinical group shows more sensory abnormalities than controls; d) if an association between food selectivity, BMI, GID, sensory dimensions and parental feeding styles can be established in both groups of children, e) if it is possible to discover similar profiles of children in both groups.