Discussion
DSM-5, DSM5
This study examined the relationship of (i) the initiation of breastfeeding and (ii) its duration with the severity of clinical presentation of children diagnosed with ASD according to DSM5 criteria and a multidimensional assessment.In our sample of 243 children with a confirmed diagnosis of ASD, 73% had been breastfed, which is comparable to the general French populationWe did not find any gender difference in our study regarding the prevalence of breastfeeding among children with ASD, which is also in line with the observation in the general populationIn our study, children with ASD who were breastfed had better daily living skills and tended to have better communication skills, according to VABS-II scores, than those who were not. This intergroup difference was not significant after adjusting for a large set of confounding factors related to the child, mother and social environment characteristics. However, our sensitivity analysis carried out only on the children for whom we had all the adjustment variables showed that the initiation of breastfeeding was significantly associated with daily living skills. We assume that this discrepancy was related to a selection bias, the 31 children with missing adjustment variables and who were not included in the sensitivity analysis, having significantly lower daily living skills than those without missing variables.We did not find any association between the initiation of breastfeeding and the severity of ASD symptoms measured by the ADOS-2 CSS or the SRS-2, which cannot be compared with the literature in the absence of published data. Furthermore, in contrast with the general populationAlthough there is some evidence in previous literature that longer duration of any and predominant breastfeeding are significantly associated with a decreased risk of ASDThis study is one of the first to examine the association between breastfeeding and the severity of clinical presentation in children with ASD. One of the strengths of our study is the large sample of children with a confirmed diagnosis of ASD following a multidisciplinary clinical assessment and using DSM-5 criteria. In addition, the assessment of clinical presentation was performed using standardised tools that target multiple dimensions, such as ASD symptoms, IQ, adaptive behaviours and behavioural problemsOur study has several limitations that need to be taken into account when interpreting the results. First, data on breastfeeding were collected retrospectively when the children were, on average, 10 years old (± 3.86), which implies a risk of recall bias. However, it has been suggested that mothers' recall of breastfeeding initiation and duration are accurate, even 6 to 20 years after childbirth