Developmental deviation in delay discounting as a transdiagnostic indicator of risk for child psychopathology
Authors: DeRosa Jacob , Rosch Keri , Mostofsky Stewart H. , Nikolaidis Aki 
Published: October 2022

Background

The tendency to prefer smaller, immediate rewards over larger, delayed rewards is known as Delay Discounting (DD). Developmental deviations in DD may play a key role in characterizing psychiatric and neurodevelopmental disorders. Recent work provided empirical support for DD as a transdiagnostic process in various psychiatric disorders. However, there is a lack of research relating developmental changes in DD from mid-childhood to adolescence to psychiatric and neurodevelopmental disorders.

Methods

The current study addresses this gap in a robust psychiatric sample of 1843 children and adolescents aged 5-18 (M = 10.6, SD = 3.17; 1219 males, 624 females). General Additive Models (GAMs) characterized the shape of age-related changes in monetary and food reward discounting for nine psychiatric disorders compared to neurotypical youth (NT; n=123). We found that over 40% of our sample possessed a minimum of at least three psychiatric or neurodevelopmental disorders. We used bootstrap-enhanced Louvain community detection to map the underlying comorbidity patterns impacting DD. We derived five subtypes based on diagnostic categories present in our sample. DD patterns were then compared across each of the subtypes. Further, we evaluated the effect of cognitive ability, emotional and behavioral problems and total household income (THI) in relation to DD across development.

Results

Higher discounting was found in six out of the nine disorders we examined relative to NT. DD was consistently elevated across development for most disorders with the exception of depressive disorders, with age-specific DD differences compared to NTs. Community detection analyses revealed that one comorbidity subtype consisting primarily of Attention-Deficit/Hyperactivity Disorder (ADHD) Combined Presentation and anxiety disorders displayed the highest overall emotional/behavioral problems and greater DD for the food reward. An additional comorbidity subtype composed mainly of ADHD Predominantly Inattentive Presentation, learning and developmental disorders showed the greatest DD for both food and monetary rewards compared to the other subtypes. Notably, this subtype had general deficits in reasoning ability, given their low performance on cognitive and academic achievement measures. Additionally, for this ADHD-I and developmental disorders subtype, THI was related to DD across the age span such that participants with high THI showed no differences in DD compared to NTs, while participants with low THI showed significantly worse DD trajectories than all others. Our results also support prior work showing that DD follows non-linear developmental patterns.

Conclusions

We demonstrate preliminary evidence for DD as a transdiagnostic marker of psychiatric and neurodevelopmental disorders in children and adolescents. Comorbidity subtypes provide insight into heterogeneity in DD across disorders and offer a unique way to identify high-risk individuals. Importantly, our findings suggest that DD is strongly related to overall intellectual reasoning ability and that, among those with lower intellectual reasoning, DD is particularly heightened in children from households with lower THI. The findings suggest that self-regulation may be particularly impaired in individuals with psychiatric and neurodevelopmental disorders with low household income.