Psychopathology and Adaptive Functioning in Children, Adolescents, and Young Adults with Noonan Syndrome

The objective of this study was to examine psychopathology and its impact on adaptive functioning in a sample of patients affected by Noonan syndrome (NS), a genetically heterogeneous condition with systemic manifestations.

Forty-two subjects affected by NS (23 males and 19 females), aged 5 to 21 years (mean 12.6 ± SD 5.1), were assessed for nonverbal cognitive abilities, with dimensional measures of psychopathology, adaptive functioning, and family quality of life.

The nonverbal intelligence quotient (IQ) mean was 99.4 ± SD 22.2, with 3 subjects (8%, 95% confidence interval [CI], 1.6%-20.9%) showing cognitive impairment (IQ<70). The Parent Child Behavior Checklist (CBCL) total psychopathology score was in the clinical range in 10% of sample and borderline in another 10%. On the Conners' Parent Rating Scales, scores suggestive of attention-deficit/hyperactivity disorder (ADHD) were in the clinical range in 20%. On the autism quotient, autism spectrum disorder symptoms were reported in 10%. Higher scores on the Adaptive Behavioral Assessment System-Second Edition and on the World Health Organization Quality of Life (26 items) were associated with lower problems on the CBCL (r = -0.63, 95% CI, -0.78 to -0.40 and r = -0.48, 95% CI, -0.69 to -0.20, respectively).

Psychopathology was common in patients with NS and negatively correlated with global functioning and family quality of life. Treatable psychopathology, such as ADHD, may constitute a treatment target for improving adaptive functioning.