Advances in the psychiatric diagnosis for intellectual and relational developmental disorders

During the last ten years the prevalence of autism and Autism Spectrum Disorder (ASD) have increased greatly. In the 60s the most reported rate was 0.5/1.000, while currently the prevalence of ASD in adults is approximately 1/100. Such rapid and significant increase in prevalence estimates raises a number of questions as to the origins of this increase. A recurring issue is the overlap and boundaries between Intellectual Developmental Disorder (lDD), coexisting ASD and Schizophrenia Spectrum Disorders (SSD). In clinical practice many People with IDD (PwIDD) have both pervasive autistic traits and a concurrent diagnoses of SSD, and many with ASD have coexisting IDD and receive a diagnosis of SSD. Furthermore people with SSD may often have a mild lDD, or borderline intellectual functioning, or other cognitive problems prior the onset of psychotic disorder. Co-occurrence of other psychiatric disorders is also frequent in the three groups, particularly in those with IDD and ASD. Differential diagnosis between SDD, lDD, and ASD (and may or may not have been clinically identified) is often challenging especially for the psychiatrist without specific training. The aim of the research project is to identify some clinical characteristics that relate most with each of the three specific conditions and their combination, which might contribute in turn to the development of better criteria of differential diagnosis and psychiatric comorbidity.