A longitudinal study of autism spectrum disorders in individuals diagnosed with a developmental language disorder as children.
BACKGROUND
A number of studies have shown that the diagnosis of developmental language disorder (DLD) can be unstable over time, such that young children with a diagnosis of DLD may show symptoms more characteristics of autism spectrum disorder (ASD) at a later date.


METHODS
To estimate the types and prevalence of ASD 469 individuals with a DLD, consecutively assessed in the same clinic during a period of 10 years, and 2345 controls from the general population were screened for ASD through the nationwide Danish Psychiatric Central Register (DPCR). The mean length of observation was 34.7 years, and the mean age at follow-up 35.8 (range: 28.3-46.7) years.


RESULTS
At follow-up, 10 (2.1%) in the DLD group and two (0.09%) in the comparison group were known in the DPCR with a diagnosis of any ASD (P < 0.0001; odds ratio = 25.5; 95% confidence interval 5.5-116.9).


CONCLUSIONS
Our results provide additional support to the notion that DLD is a marker of increased vulnerability to the development of ASD.
Mouridsen
S E
SE
Department of Child and Adolescent Psychiatry, Bispebjerg University Hospital, Copenhagen, Denmark. sem01@bbh.hosp.dk
Hauschild
K-M
KM