Alterations in gray matter volume and cortical thickness in medication-naive offspring with ADHD and a parental history of bipolar disorder.

BACKGROUND

Bipolar disorder (BD) is a high heritability rate mental disorder. Attention-deficit/hyperactivity disorder (ADHD) in offspring of individuals with BD may manifest as a prodromal stage of BD and have distinct neuroimaging features compared to typical ADHD.

METHODS

We conducted a cross-sectional involving 101 medication-naive participants aged 8 to 15 years dividing into three groups: BD offspring with ADHD (n = 21), non-BD offspring with ADHD (n = 36), and healthy controls (n = 44). Voxel-based morphometry and Surface-based morphometry methods were used to calculated gray matter volume and cortical thickness of three groups. After conducting the aforementioned analyses, we pooled all ADHD patients into a single cohort and conducted correlation analyses between the SNAP-IV subscale scores and the mean values of differential brain regions.

RESULTS

Significant reductions in gray matter volume were observed in BD offspring within the limbic system compared to both other groups. Cortical thickness thinning was found in bilateral precentral gyri, bilateral fusiform gyri, bilateral parahippocampal gyri, bilateral temporal pole in BD offspring compared to both other groups. Non-BD offspring showed decreased cortical thickness in the bilateral precentral gyrus when compared to HCs. The severity of ADHD hyperactivity/impulsivity symptoms is negatively correlated with cortical thickness in the precentral gyrus.

CONCLUSIONS

Offspring of individuals with BD diagnosed with ADHD exhibit more pronounced brain structural alterations than those with typical ADHD, suggesting these changes may represent the genetic abnormalities underlying bipolar disorder.