Age at Autism Diagnosis in the Norwegian Mother, Father, and Child Cohort Study (MoBa): Exploring the Association With Family Well-Being.

For many autistic individuals, close family members represent a crucial source of support throughout their lifetime. Early autism diagnosis is thought to benefit both autistic individuals and their family members by facilitating early access to services and information. However, little research has empirically studied the relationship between age at diagnosis and well-being among autistic individuals and their family members. In this study, we examined predictors of age at autism diagnosis and its relationship with family well-being using the population-based Norwegian Mother, Father, and Child Cohort Study (MoBa). We found that the most important factors associated with a later age at diagnosis were fewer social communication difficulties at age three, fewer maternal concerns about development in early childhood, absence of a co-occurring intellectual disability diagnosis, female sex, and having older siblings. While a later age at diagnosis was associated with higher well-being for mothers and children during childhood, it was associated with lower well-being for children during adolescence. All associations were substantially attenuated after adjustment for various clinical, demographic, and genetic factors - reflecting complex patterns of confounding. We argue that future research should aim to leverage public awareness campaigns, screening programmes, or changes in clinical practice to understand the causal mechanisms underlying these relationships.Lay abstractFamily members of autistic people are often an important source of support for their well-being. An earlier autism diagnosis might be helpful for autistic individuals and their families, because families might receive professional support sooner. However, the impact of an earlier diagnosis is difficult to study, because many child and family characteristics that lead to an earlier autism diagnosis may have their own influence on well-being in autistic individuals and their families. In this study, we look at how age at diagnosis and family well-being are related and how they both relate to different child and family characteristics. We find that children, on average, receive a later autism diagnosis when they have fewer social communication difficulties and fewer maternal concerns in early childhood, do not also have an intellectual disability diagnosis, are a girl, or have older siblings. We also found that a later autism diagnosis was associated with higher well-being for children and mothers in childhood but with lower well-being for children in adolescence. When we compared families with similar child and family characteristics, we no longer saw such clear links between age at diagnosis and well-being. This might be because of the complex mixture of influences child and family characteristics have on both age at diagnosis and well-being and suggests that other types of study may be better for investigating the impact of age at diagnosis on well-being in families.