A longitudinal study of personality disorders in individuals with and without a history of developmental language disorder.

Traditionally developmental language disorders (DLDs) have been studied with focus on psycholinguistic and cognitive implications, and little is known of the long-term psychosocial outcomes of individuals diagnosed with a DLD as children. The objective of this study was to compare the prevalence rates and types of personality disorders (PDs) in a clinical sample of 469 individuals diagnosed as children with DLD, with PDs in 2,345 matched controls from the general population without a known history of DLD, using data from the nation-wide Danish Psychiatric Central Register (DPCR). The average observation time was 34.7 years, and mean age at follow-up was 35.8 years. Of the 469 individuals with DLD, 23 (4.9%) were known in DPCR with a PD diagnosis, compared with 51/2,345 (2.2%) in the control group (P =0.0007). Variables at assessment in childhood (gender, IQ, presence of a receptive language disorder, and degree of receptive and expressive language disorder) were not associated with a PD diagnosis in the DPCR at follow-up. Our results provide additional support to the notion that DLD is a marker of increased vulnerability to the development of a PD in adulthood and emphasizes that more research is needed to understand the links between a diagnosis of DLD in childhood and a PD in adult years.