The findings, published in JAMA Network Open, suggest that the increased health risks reflect a combination of factors linked to ADHD itself, as well as the way society responds to people with the condition throughout adulthood.

The study is one of the largest and longest of its kind, tracking health outcomes over several decades to examine the long-term impact of childhood ADHD traits.

Senior author Professor Joshua Stott from UCL’s Division of Psychology and Language Sciences said the results add to growing evidence that people with ADHD face poorer health outcomes across their lifespan.

“People with ADHD can thrive with the right support, but this is often lacking,” Professor Stott said. “This is partly due to a shortage of tailored services and partly because ADHD remains underdiagnosed, particularly among people in midlife and older age, leaving many needs unmet.”

ADHD is characterised by differences in attention regulation, hyperactivity and impulsivity. While people with ADHD often display high energy and an ability to focus intensely on areas of interest, they may struggle with routine tasks, planning and time management. These challenges can affect educational and work outcomes, leading to longer-term social and health consequences.

Although ADHD begins in childhood and frequently persists into adulthood, it remains under-treated in adults in the UK compared with other high-income countries, with support services continuing to be under-resourced.

Supported by the Medical Research Foundation, the researchers analysed data from 10,930 participants in the UCL-led 1970 British Cohort Study, which has followed individuals from birth into middle age.

ADHD traits were assessed using behaviour questionnaires completed by parents and teachers when participants were 10 years old, regardless of whether the child had received a formal ADHD diagnosis.

The analysis showed that individuals with high ADHD trait scores at age 10 had 14% higher odds of reporting two or more physical health conditions by age 46. These conditions included migraine, back problems, cancer, epilepsy and diabetes. Among those with high childhood ADHD traits, 42% reported two or more physical health problems in midlife, compared with 37% among those without high traits.

The study also found that people with high ADHD traits in childhood were more likely to report physical health-related disability in midlife, defined as difficulties with work or daily activities due to physical health problems.

Further analysis suggested that poorer health outcomes were partly explained by higher rates of mental health problems, increased body mass index (BMI) and higher smoking rates among people with ADHD. Previous research has also shown that individuals with ADHD are more likely to experience stressful life events, social exclusion and delays in accessing screening and medical care.

Notably, the association between childhood ADHD traits and physical health-related disability appeared to be stronger in women than in men.

Professor Stott added: “These findings align with what we know about ADHD — including difficulties with impulse control, a heightened need for immediate reward, and higher rates of mental health challenges, often driven by social disadvantage.”

A separate study published last year by the same research group found evidence of reduced life expectancy among adults diagnosed with ADHD, although life expectancy was not examined in the current research.

Lead author Dr Amber John, who began the study at UCL before moving to the University of Liverpool, stressed that outcomes vary widely.

“People with ADHD are a diverse group with different strengths and experiences, and most will go on to live long, healthy lives,” she said. “However, many face significant barriers to timely diagnosis and appropriate support.”

Dr John added that improving access to diagnosis, treatment and tailored support could help improve both physical and mental health outcomes for people with ADHD. She also called for public health strategies to better accommodate the needs of people with ADHD, including more accessible screening programmes and ongoing health monitoring.