Problem Behaviours and Major Depressive Disorder in Intellectual Disability and Autism: A Contribution of PET and MRI

Background: Previous literature demonstrates a high association between problem behaviours (PB) and major depressive disorder (MDD) in intellectual disability (ID) and autism (ASD). Neuroradiological literature about this topic is still scarce. Aims: The present study aims at integrating neuro-imaging findings (PET, MRI). Methodology: Two groups with mild-to-moderate ID and ASD with PB (n = 30; MDD = 15) and without (n = 12; MDD = 1) were formed. PB was assessed by the Dutch version of Disturbing Behavior Scales for Intellectual Disability. MDD was screened with the use of the DM-ID (Diagnostic Manual-Intellectual Disability). Every patient received a structural MRI (volumetry hippocampus and amygdala) and at least every second patient a PET scan Results: MDD versus no-MDD as a whole (± PB) demonstrated hypermetabolism cerebellum, brainstem, pallidum. Furthermore, MDD in ID, ASD, PB versus no PB correlated with hypermetabolism in cerebellum, and hypometabolism in the middle frontal and precentral gyrus. PB (+/- MDD) first PET scan versus second PET scan (after a minimum 6 months of treatment) demonstrated hypometabolism of the precentral gyrus. In the case of no-PB and MDD versus no-MDD, hypometabolism cerebellum and precentral gyrus could be screened. PB and MDD versus no-PB and no-MDD demonstrated hypermetabolism pallidum. Summarizing the structural MRI results, the volumes of the hippocampus and amygdala did not show a significant correlation with PB or MDD. Conclusion: ASD, PB and MDD in ID are mutually enhancing factors in hypometabolism precentral gyrus and mid-frontal gyrus. MDD and PB in ID and ASD are correlated with hypermetabolism cerebellum and pallidum. PET data are discussed in relation to the high association between PB and MDD in ID and ASD.

Publication year:2017