According to study, people who receive an adult diagnosis of attention deficit hyperactivity disorder (ADHD) may be more susceptible to dementia in old age.
Although experts emphasised that further research is required to determine whether the apparent connection is causal and whether ADHD drugs reduce the risk of dementia, they said the study underscores the need to explore potential linkages further.
Results from a review of more than 100,000 patients’ medical records revealed that those with adult ADHD diagnoses appear to be at nearly three times the risk of developing dementia in later life.
According to the research team, adult ADHD-related processes may lessen the brain’s capacity to counteract the impacts of processes that can occur later in life, such as neurodegeneration or changes in blood supply to the brain.
According to Dr. Stephen Levine, the study’s first author and a professor at the University of Haifa,
“This is consistent with the primary result that adult ADHD increases dementia risk, as well as mild evidence of reverse causation.”
The researchers examined the electronic health records of the Israeli nonprofit health maintenance organisation (HMO), Meuhedet Healthcare Services, and they describe their findings in the journal Jama Network Open. Participants who already had a dementia or ADHD diagnosis were not included in the study.
The team examined the records of 109,218 participants, who were, on average, 57.7 years old when the study started in January 2003. They followed their progress until either their deaths, leaving the HMO, dementia diagnosis, or the trial’s conclusion in February 2020, whichever happened first.
The findings showed that 730 persons received adult ADHD diagnoses over the study period, 96 (13% of them) also received dementia diagnoses. In comparison, among individuals who did not have adult ADHD diagnoses, there were 7,630 diagnoses of dementia (7%) in total.
Age, sex, socioeconomic level, smoking, and a number of medical disorders were all taken into account by the research team, who discovered that people who were diagnosed with adult ADHD throughout the study had a 2.77 times greater risk of
The outcomes also revealed that treatment for ADHD altered the situation.
The researchers conclude that further research was necessary because there was “no clear association” between ADHD and dementia risk among people who had exposure to psychostimulant medications (used to treat ADHD).
Levine did point out that the study was unable to establish causation and that the team was unable to determine whether the findings applied to children with ADHD.
The second point was emphasised by Prof. Roxana O Carare of the University of Southampton, who was not involved in the study. She suggested that future research may examine if the changes in neurotransmitter levels in the brain seen in ADHD were associated with a higher risk of acquiring dementia.
Prof. Chris Hollis of the University of Nottingham, however, asserted that a variety of factors might be muddying the waters. He said that it would also be comforting if dementia diagnosis was independently validated by brain imaging. “Those adults who seek and receive an ADHD diagnosis are also more likely to be assessed for other cognitive/neuropsychiatric conditions including dementia,” he said.
In particular, ADHD patients shouldn’t be frightened, he said. “More research is needed to confirm this association, and if it is, a key question would be whether ADHD medication reduces this potential risk.”
A major finding from the research, according to Henry Shelford, chief executive of the nonprofit organisation ADHD UK, was the necessity of learning much more about ADHD and its side effects. “Right now, ADHD in the UK is struggling to get proper recognition, let alone important deep research,” the man stated.