High Prevalence of Non-psychotic Delusions in Children with High-functioning Pervasive Develonmental Disorder.

Background: Non-psychotic delusions are reported to be associated with depression and anxiety. When these delusions occur in high-functioning pervasive developmental disorder (HFPDD) children, they are often misdiagnosed as schizophrenia and have consequently been studied less. This study has three goals: to investigate the prevalence of non-psychotic delusions in HFPDD children, to test the hypothesis that HFPDD children are more likely to have non-psychotic delusions than non-HFPDD children, and to test the hypothesis that non-psychotic delusions are associated with depression and anxiety.

Methods: This is a cross-sectional and case-control study. The participants were 45 HFPDD children (cases) and 51 children without HFPDD (controls). Semi-structured interviews were conducted to assess the presence of non-psychotic delusions. We used the Child Behavior Checklist (CBCL) to assess levels of anxiety and depression.

Results: Of the cases, 62.2% had non-psychotic delusions, which was significantly higher than controls (25.5%, p<0.001, OR: 4.81, 95% CI: 2.01-11.51). Cases tended to score higher for internalizing problems (including anxiety and depression) on the CBCL than controls (69.8±9.4 vs 65.9±10.4, t= 1.9, p=0.062). Cases with non-psychotic delusions scored significantly higher for internalizing problems in CBCL than children without non-psychotic delusions (72.2±7.7 vs 65.7±10.7, t=2.4, p= 0.022).

Conclusions: More than half of the HFPDD children were suffering from non-psychotic delusions, and these delusions were associated with anxiety and depression. Therefore, accurate diagnoses of non-psychotic delusions should be conducted for appropriate treatments to be prescribed.