There is growing recognition that attention deficit hyperactivity disorder (ADHD) is more than just a devastating childhood disorder, with a conservative estimate of 8.7 million adults in the United States living with the disorder, both diagnosed and undiagnosed. However, not only have seniors aged 50 and older been excluded from ADHD research, they even face barriers when seeking help.
Researchers at Sweden's Örebro University examined international registry data and community-based studies on more than 20 million people around the world, including 41,000 people diagnosed with ADHD, and found that as of 2020, only 32 datasets in 20 papers took older adults into account.
"A significant number of adults aged 50 and older have elevated levels of ADHD symptoms. But many of them are not diagnosed or treated," said study author Maja Dobrosavljevic, a researcher at Örebro University.
Although ADHD is a neurodevelopmental disorder, most people don't "outgrow" it. Moreover, it is a complex disease that is difficult to diagnose and treat.
People with ADHD have a deficiency in the brains of the neurotransmitter norepinephrine, which is closely related to dopamine and regulates the brain's reward and pleasure centers. In addition, ADHD patients also suffer from impaired function in the brain's frontal cortex, limbic system, basal ganglia, and reticular activating system, resulting in short-circuiting of neural communication and a range of symptoms that vary greatly from person to person.
It is an extremely complex neurological disorder that is more difficult to detect in older adults because many of the symptoms are characteristic of age-related cognitive decline.
"One of the reasons why many older adults go undiagnosed is that the symptoms are often mistaken for the natural aging process or early stages of dementia," Dobrosavljevic said.
Behaviors such as forgetfulness, poor memory and mood swings may be overlooked as symptoms associated with aging, while older adults with ADHD are also more likely to develop dementia, high blood pressure, heart failure, stroke, type 2 diabetes and obesity.
"People with ADHD are at a significantly higher risk of developing dementia and mild cognitive impairment, which affects their ability to remember, receive and process information," Dobrosavljevic said.
Because ADHD is hereditary, the researchers believe it would be a huge oversight to exclude so many people from the study and not review diagnostic systems that currently favor children and young adults.
"Raising awareness about ADHD in this age group is important because it will allow more people to receive the correct diagnosis and appropriate treatment," Dobrosavljevic said.
The study was published in the journal Expert Review of Neurotherapeutics.