People with ADHD have shorter life expectancy and higher risk of mental health issues, study finds

People walk through a tunnel in Berlin, Germany, Wednesday, Nov. 22, 2023. THE CANADIAN PRESS/AP/Markus Schreiber (Markus Schreiber/THE CANADIAN PRESS)

Having attention deficit hyperactivity disorder, or ADHD, is associated with a shorter life expectancy and a greater risk of mental health issues, according to a new study of more than 30,000 people with the disorder in the United Kingdom.

Men diagnosed with ADHD had a reduction in life expectancy by 4 ½ years to nine years, while women’s life expectancy was shortened by 6 ½ years to 11 years, according to the study published Thursday in The British Journal of Psychiatry.

“Although many people with ADHD live long and healthy lives, our finding that on average they are living shorter lives than they should indicates unmet support needs,” said lead study author Dr. Liz O’Nions, honorary research fellow in clinical, education and health psychology at University College London, in a news release. “It is crucial that we find out the reasons behind premature deaths so we can develop strategies to prevent these in the future.”

Attention deficit hyperactivity disorder is a neurodevelopmental disorder that’s commonly diagnosed in childhood but often lasts into adulthood. People with ADHD have imbalanced neurotransmitters, one of which is dopamine. It’s a key neurotransmitter in the brain’s prefrontal cortex required to help us with executive function and self-regulation skills, which involve planning, focusing and sustaining attention, remembering instructions and multitasking.

People with ADHD may feel restless or have trouble concentrating, staying organized, managing their time or prioritizing, hyperfocusing or controlling their impulses. These symptoms can affect all areas of life.

At least three per cent to four per cent of adults in the UK have ADHD, with the prevalence in children estimated to be at least four per cent. But it’s possible many more people go undiagnosed, which could mean the life expectancy gap the study authors found could be overestimated, they said.

The new findings affirm those of recent research, such as a 2022 study that found greater premature death risk among people with ADHD or autism in both the United States and Europe. But the current study, to the authors’ knowledge, is the first to use mortality data to employ the life-table method: a statistical technique for analyzing death rates and the probabilities of survival or death at different age intervals.

The research team reviewed primary care data from 30,029 adults with ADHD and compared them with nearly 300,400 participants who didn’t have ADHD but were matched by age, sex and primary care practice.

Besides the differences in life expectancy, the analysis also revealed ADHD to be linked with a higher risk of mental health issues — such as anxiety, depression, self-harm, suicide and personality disorders. Autism, intellectual disabilities, harmful habits such as smoking or “potentially harmful alcohol use,” and physical health problems including diabetes or high cholesterol were more common in this group as well.

Why ADHD could affect one’s life expectancy

The study is “striking” but is based on observational data that inevitably leaves many important questions unanswered since a cause-and-effect relationship can’t be entirely established, Dr. Kevin McConway, emeritus professor of applied statistics at the Open University in England, said in a news release. He was not involved in the research.

“What can be done about this? That depends on whether the reductions in average life expectancy are caused (somehow) by ADHD, and if they are, how they are caused,” McConway said.

In the UK, treatment for ADHD and accompanying conditions is lacking, especially for adults since recognition of adult ADHD is still evolving, experts said. This insufficiency could partly explain the differences in life expectancies.

But there also may be “some factors that arise before birth or in very early life that could separately affect the chance that a person is later diagnosed with ADHD” and dies earlier than usual, McConway said. Those could be genetic or environmental. Additionally, the authors either didn’t have details on, or didn’t control for, race or ethnicity and socioeconomic factors, which can affect life expectancy.

The researchers also couldn’t determine “when ADHD was diagnosed in relation to other medical problems, or the impact of treatment,” said Dr. Oliver Howes, professor of molecular psychiatry at King’s College London, in a news release. Howes wasn’t involved in the study.

However, “things like differences in smoking, alcohol use, and several health conditions are likely to be consequences of the ADHD, to a large extent,” McConway said — meaning those vices and conditions could explain how ADHD could affect death rates or lead to shorter life expectancies.

Details on the causes of early deaths of study participants also weren’t available to the researchers.

Treating ADHD

People with ADHD “have many strengths and can thrive with the right support and treatment,” said senior study author Dr. Josh Stott, professor of aging and clinical psychology at University College London, in a news release.

Experts on the topic have said that addressing the issue of premature mortality among people with ADHD starts with health care providers who should routinely collect details on behavioral and medical conditions and health outcomes related to the disorder. Doing so can help providers and patients address risk factors and prevent delays in treatment.

Some organizations have resources for how people with ADHD can increase their likelihood of engaging in tasks, habits or activities that can help improve their quality of life and life expectancy, including exercise, proper nutrition, dental care and sleep hygiene.

Mental health professionals specializing in ADHD can help patients develop coping skills for any symptoms that may lead to distress or other outcomes that negatively affect their lives.

They can also discuss whether ADHD medications would be useful. A study of nearly 150,000 Swedish people with ADHD, published in March 2024, found medication use was associated with a 19 per cent decrease in mortality risk within two years post-diagnosis.

Kristen Rogers, CNN