The naturalistic follow-up of pervasive developmental disorders–not otherwise specified cases

OBJECTIVES: Pervasive developmental disorders (PDDs) are neurodevelopmental disorders characterized by deficits in social interactions, communication impairments, and the presence of restricted interests and stereotyped behaviours. The issue of diagnostic stability, course, and prognosis of PDDs is an increasing focus of research studies. The aim of this study is to evaluate the individuals who were previously diagnosed with pervasive developmental disorders–not otherwise specified (PDD–NOS) (one of the sub-diagnoses of PDDs) under age six years with respect to their current diagnoses.

METHODS: The participants were selected among the patients who were diagnosed with PDD– NOS under six years of age in our outpatient clinic. We obtained 208 patients’ file records. We were able to reach 92 patients’ parent by telephone and 58 parents accepted to voluntarily participate. After the excluded cases, finally 51 patients were evaluated in this cross-sectional naturalistic follow-up study. Children Autism Rating Scale (CARS) and Kiddie-Schedule for Affective Disorders and Schizophrenia (K-SADS) were administered to participants; Autism Behavior Checklist (ABC) was completed by their parents.

RESULTS: There were 44 (86.3%) male and 7 (13.7%) female participants in the study. The current mean age was 8.62 years (SD = 2.25). The mean age at the time of first diagnosis was 3.56 years (SD = 1.22). The mean duration of the follow-up period was 5.05 years (SD = 2.27). Forty-five (88.2%) of 51 patients remained to have one of the PDDs (23 autistic disorder, 22 PDD–NOS) according to DSM-IV-TR. Six patients (11.8%) did not meet the diagnostic criteria of any PDDs. Two of these six patients diagnosed with attention-deficit/hyperactivity disorder and one with mild-level intellectual disability.

CONCLUSIONS: It was observed that 11.8% patients who diagnosed as PDD–NOS less than six years old were found to be off the PDD spectrum. PDD–NOS diagnosis stability was found 43.1% and 45.1% of the patients moved to another PDD diagnosis. These findings should be supported with further studies in Turkey, by increasing sample size, and follow-up duration for understanding the course.