2/19 Chronic Fatigue in ADHD & Immune Function

Our paper for Tuesday!: Quadt, L., Csecs, J., Bond, R., Harrison, N. A., Critchley, H. D., Davies, K. A., & Eccles, J. (2024). Childhood neurodivergent traits, inflammation and chronic disabling fatigue in adolescence: A longitudinal case-control study. BMJ Open, 14(7), e084203.

Most explanations for fatigue in neurodivergent people point to masking, cognitive overload, or poor sleep. But a 2024 longitudinal study out of Brighton and Sussex Medical School asks a different question: what if inflammation itself is part of the story? This week, we're reading a case-control study that tracked neurodivergent traits, inflammatory markers, and chronic fatigue from childhood into adolescence.

Some discussion questions:

• Do neurodivergent traits in childhood predict chronic fatigue in adolescence? Quadt et al. used a longitudinal design to track whether children with higher neurodivergent trait scores were more likely to develop chronic disabling fatigue by adolescence — and found that the relationship held even when controlling for other variables. (Quadt et al., 2024)

• Where does inflammation fit in? The study examined inflammatory markers as a potential mechanism linking neurodivergent traits to fatigue outcomes — asking whether immune differences help explain why fatigue is so disproportionately common in neurodivergent populations, rather than treating it purely as a behavioral or psychological phenomenon. (Quadt et al., 2024)

• What makes this study design different? Most research on neurodivergence and fatigue is cross-sectional — a snapshot. This is longitudinal and case-controlled, meaning it can speak to timing and direction in a way most studies can't. That matters when you're trying to distinguish cause, consequence, and correlation. (Quadt et al., 2024)

• Does immune state affect day-to-day cognitive functioning? If inflammation mediates fatigue in neurodivergent adolescents, the implications extend beyond tiredness — fatigue is itself a driver of reduced attention, slower processing, and emotional dysregulation. The paper opens the question of whether fluctuating immune state contributes to the variability in functioning that neurodivergent people often experience. (Quadt et al., 2024)

• What does this mean for how we explain "inconsistency"? Neurodivergent people are frequently told their inconsistent functioning reflects effort or motivation. If immune-mediated fatigue is genuinely part of the picture, that framing may be not just unhelpful but biologically inaccurate. (Quadt et al., 2024)

• If you could design the next study, what would it look like? Quadt et al. establish a longitudinal association between neurodivergent traits, inflammation, and fatigue — but key questions remain open. What inflammatory markers matter most? Does the relationship hold across different neurodivergent diagnoses separately? Would an intervention targeting inflammation reduce fatigue outcomes? We'll close by thinking through what a follow-up study would need to include — sample, design, measures, and controls — to actually answer what this paper leaves unresolved. (Quadt et al., 2024)