A new study out of the U.K. found that people diagnosed with attention deficit hyperactivity disorder, or ADHD, have a lower life expectancy.

The study, published Thursday in the British Journal of Psychiatry, also found adults with ADHD on average experience poorer educational and employment outcomes and worse physical and mental health.

The life expectancy of men with ADHD was shortened by four to nine years, while the lifespan of women with the disorder was shortened by six to 11 years, according to the study.

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Nearly 3% of adults have been diagnosed with ADHD, but researchers said many who have the condition have not been diagnosed.

The authors of the study said it’s the first to look at mortality data in connection to those diagnosed with the disorder.

The study was conducted by looking at primary care data from over 30,000 adults with ADHD and 300,000 without it.

“We believe that this is likely caused by modifiable risk factors and unmet support and treatment needs in terms of both ADHD and co-occurring mental and physical health conditions,” the authors of the study wrote.

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