An observational study is one that aims to collect data from routine clinical practice, without altering a patient's standard diagnostic and therapeutic pathway (no additional instrumental or laboratory tests beyond those performed in clinical practice are envisaged).

The overall objective of this study is to investigate sleep disorders in preschool-aged children with Autism Spectrum Disorder. Sleep plays a key role in early brain development. The prevalence of sleep disorders in childhood is reported to be between 10 and 50%, with a prevalence of up to 86% in children with neurodevelopmental disorders. Over the past few decades, numerous studies have demonstrated a significant bidirectional connection between sleep problems and various areas of child development. Therefore, early identification of sleep disorders in childhood is essential for adequate treatment and prevention of negative cognitive and socioemotional impacts.

Recent studies have demonstrated a hypothetical role for vitamin D and iron in regulating sleep. The objectives of the study are to describe sleep disturbances in a group of preschool-aged subjects with ASD (18-60 months), to measure blood ferritin and vitamin D levels, and to assess a possible correlation with specific subtypes of sleep disturbances.

Given the impact that sleep disturbances have on various areas of children's development, secondary objectives include assessing a possible positive correlation between the severity of sleep disturbances and symptoms related to Autism Spectrum Disorder and/or other psychiatric comorbidities.

Inclusion Criteria:

• Subjects with ASD
• aged between 18 months and 60 months

Exclusion Criteria:

- Subjects with neurologica theraphy

subjects with ASD aged between 18 months and 60 months