Risk factors and the evolution of psychosis in 22q11.2 deletion syndrome: a longitudinal 2-site study

22q11.2 Deletion syndrome (22q11.2DS) is associated with high rates of schizophrenia, other neuropsychiatric disorders, and cognitive deficits. The objectives of this 2-center study were to longitudinally assess the trajectories of psychiatric disorders in 22q11.2DS from childhood to adulthood, and to identify risk factors for their emergence.

A total of 125 children and adults with 22q11.2DS were evaluated at 2 time points, baseline and follow-up (4 years apart), using standardized psychiatric and cognitive measures.

The rate of mood disorders tended to decrease during childhood and increase during late adolescence. Statistically significant predictors for the presence of a psychotic disorder as well as the severity of positive symptoms at follow-up were identical, and consisted of an anxiety disorder at baseline, lower baseline Full Scale IQ, and a greater decrease in verbal IQ scores between time points. Nine of 10 individuals with an emerging psychotic disorder had an anxiety disorder at baseline. The age of onset for a psychotic disorder was between 14 and 22 years in 82.6% of cases.

It is important to evaluate the presence of anxiety disorders in children and adolescents with 22q11.2DS, as they are major risk factors for the emergence of psychotic disorders, which usually occur during late adolescence in this at-risk population.