UCL study reveals broad mortality risks faced by ADHD individuals

For the study, published in JAMA Network Open, the researchers conducted a systematic review and meta-analysis of 19 studies that included data from close to 16 million study participants on three continents. 

In a meta-analysis of observational studies, they found that ADHD is linked to higher rates of suicide and injury deaths, as well as a moderate increase in natural-cause mortality. But they found some evidence that this mortality risk is lower among people who take ADHD medication. 

Senior author Professor Joshua Stott (UCL Psychology and Language Sciences) said: "We have previously found that people with ADHD have reduced life expectancies, so here we are adding to our understanding of what drives this very concerning statistic. 

"We found that people with ADHD face an increased risk not only of death by suicide and injury, but also of deaths by natural causes, adding to evidence that health inequalities faced by people with ADHD are broad and wide-ranging. 

"ADHD is not by definition a life-limiting condition as the right support and treatment can help people with ADHD to live long and healthy lives. Our findings underscore the importance of ensuring that everyone who may have ADHD has access to accurate diagnosis and treatment. While ADHD diagnosis rates have risen in recent years, they may still lag behind actual prevalence, particularly for older age groups where mortality risk may be most pertinent." 

The researchers reviewed evidence from 19 studies that tracked large numbers of people with and without ADHD for multiple years, in some cases following up study participants for over 20 years, in order to compare mortality rates between groups. 

They found that people with an ADHD diagnosis had a 70% higher rate of death from any cause than people without an ADHD diagnosis. The rate of death by suicide was 90% higher among people with ADHD, and the rate of death from injuries, whether intentional or accidental, was 55% higher. The rate of death from natural causes was 27% higher. 

The researchers point to evidence that people with ADHD are more likely to experience mental health problems and face challenges with emotional regulation, impulse control and risk-taking. They also experience more societal exclusion, disadvantage, and stigma. Unintentional injury deaths, such as road deaths, may also be linked to differences in attention. 

In previous research, the authors found that people with ADHD experience higher rates of physical health conditions such as cardiovascular disease, metabolic disorders, diabetes or cancer. Mortality from natural causes may be linked to health risk behaviors such as smoking or alcohol use. People with ADHD may also experience challenges with engagement and access to health care, and with adherence to medical treatment. 

Among people with ADHD, those who take ADHD medication appeared to have a 25% lower mortality risk, although the researchers caution that this finding was only based on three of the 19 included studies. 

Our findings provide early evidence to suggest that medication may play an important role in supporting the health of people with ADHD, but this is based on a small number of studies and further research is needed to clarify this link. And medication is just part of the story; many people with ADHD benefit from comprehensive, long-term treatment and support." 

Lucy Corrigan, First Author, University of Liverpool

Senior author Dr Amber John (UCL Psychology and Language Sciences and University of Liverpool) said: "Many people with ADHD face challenges throughout their lives, so equitable access to evidence-based assessment and treatment is vital to ensure they can live long, healthy lives." 

Study limitations 

The researchers say there were broad differences between the studies included in their analysis – while they did generally find that ADHD is linked to higher mortality, the different studies had very disparate results as to the magnitude of this effect. 

The authors advise particular caution in interpreting the results around ADHD medication use, and it is based on a small number of studies and importantly as all studies included in the review were observational it is not possible to infer causality.