Multigenerational study finds links between ADHD and risk of dementia
Attention-deficit/hyperactivity disorder (ADHD) appears to be somehow linked to risk of dementia and Alzheimer’s disease, a new multigenerational study has found. Parents and grandparents of people with ADHD have a higher risk of Alzheimer’s and dementia than people with no ADHD in their family, Swedish researchers said.
Specifically, parents of an ADHD child have a 34% higher risk of dementia and 55% higher risk of Alzheimer’s, the results showed. Grandparents have about an 11% increased risk of either condition.
“ADHD is associated with dementia across generations,” said lead researcher Le Zhang, a doctoral candidate with the Karolinska Institute’s department of medical epidemiology and biostatistics, in Stockholm. “Our study calls attention to advancing the understanding of ADHD and cognitive decline in older age.”
However, it’s unclear what might tie the two conditions together, the researchers said.
The largest genetic studies on ADHD and dementia to date “have failed to detect any genetic variant in common,” Zhang said.
But she noted that “there have been studies suggesting that certain genes may be implicated in both ADHD and dementia.”
Another possibility is that outside influences on health might increase the risk of both diseases within a family, such as financial distress, obesity or substance use, Zhang said.
For the study, Zhang and her colleagues analyzed data on more than 2 million people born in Sweden between 1980 and 2001.
The study was recently published online in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.