Researchers find ADHD linked to chronic pain, immune disorders, and other health conditions

ADHD, one of the most common neurodevelopmental conditions in the United States, has long been understood primarily as a brain-based disorder affecting attention and impulse control. But researchers are increasingly examining how it may interact with the rest of the body, with accumulating evidence pointing to connections between ADHD and a range of chronic physical and immune-related conditions.

A study published in Scientific Reports this spring examined 958 adults with treatment-resistant chronic pain and found that those reporting "extremely severe" pain — rated 9 or 10 on a 10-point scale — were more likely to have ADHD symptoms than those with less severe pain. Overall, ADHD symptoms were about twice as common in the study group as in the general population, according to the Washington Post's reporting on the research.

Experts cited in the Post's coverage offered several mechanisms that may help explain the ADHD-pain connection. Clinical psychologist Karen Stewart described how impulsivity and cognitive rigidity — both common ADHD traits — can amplify the perception of pain through catastrophizing and an inability to reframe negative thoughts. Neuroscientist Valentin Dragoi pointed to central sensitization, in which the nervous system becomes hypersensitive to sensory signals, as a phenomenon more common in people with ADHD. Neuroinflammation — inflammation of brain or spinal cord tissue considered one factor in ADHD — may additionally disrupt how neurons communicate and heighten the nervous system's sensitivity over time.