Adults with attention deficit hyperactivity disorder, otherwise known as ADHD, may face a shorter life expectancy than their peers.

On average, men with ADHD died seven years earlier than men without it, while women with ADHD died nine years earlier than their counterparts, according to a study of more than 30,000 people published Thursday in The British Journal of Psychiatry. 

“It’s a big number, and it is worrying,” Joshua Stott, lead study author and professor of aging and clinical psychology at University College London, told The New York Times. 

The study didn't identify specific causes of death, but found that people with ADHD were more likely to smoke, abuse alcohol and have other health issues like depression, self-harm or personality disorders.

ADHD is often associated with impulsive behaviors and difficulty managing time or health, which can lead to riskier choices, Stott explained.

These challenges can lead to higher rates of accidents and chronic health conditions, The Times reported.

Previous research supports these findings. A 2022 meta-analysis found that people with ADHD were nearly three times more likely to die from unnatural causes, such as accidents or suicides. 

What's more, a 2019 study linked ADHD to reduced life expectancy due to smoking, alcohol use, poor sleep and lower income.

Russell Barkley, lead author of that study, said the data made it clear that ADHD should not be seen as a childhood disorder, like bed-wetting, but as a lifelong problem.

Health care systems should be able to adapt to better support people with ADHD, Stott explained to The Times. This could include more tailored care for those struggling with communication, sensory sensitivity or managing time.

“If it’s about systems, it’s malleable,” Stott said. “This doesn’t have to be.”

Experts emphasized that better support could prevent risks tied to ADHD. “There are risk factors to work on,” Stephen Hinshaw, a psychology professor at the University of California, Berkeley, who studies ADHD but was not involved in the study, told The Times. 

“That is the key limitation of the study, because it would be really important to know, in terms of prevention, should we be focused on suicidality? Better diet and exercise? Depression?”

Historically, many people with ADHD — especially women and people of color — were underdiagnosed, The Times reported.

And while diagnoses among older adults have increased in recent years, Stott noted that they may have been viewed dismissively by caregivers.

“If you’re constantly told, as a kid, sit down, stop being so naughty -- if you talk to people with ADHD, that is their experience -- stop talking, go and sit outside,” Stott concluded. “It’s all of these things that wear down at your life chances, in many ways.”