New research has uncovered a surprising link between a heart condition and early-onset dementia.
Atrial fibrillation (AF) is a heart condition characterised by an irregular rhythm in the heart’s upper chambers. More than 1.5 million people in the UK have been diagnosed and an additional 270,000 may be living with the condition undiagnosed, according to a 2023 report by the British Heart Foundation.
Since 2013, AF diagnosis rates have surged by 50%, making the new research particularly concerning.
The findings, presented at a scientific congress of the European Society of Cardiology, revealed that younger people with this heart arrhythmia were more likely to develop dementia.
People aged between 65 and 70 with AF faced a 21% higher risk of dementia, but this correlation completely disappeared over the age of 70 and became stronger in younger individuals.
The study analysed anonymised health data for over two million people in Catalonia, Spain as reported by News Medical.
Those under 65 faced an even higher 36% increased risk. A dementia diagnosis before the age of 65 is referred to as early-onset dementia.
Early-onset dementia is not as rare as some might think, with approximately 7.5% of dementia patients in the UK believed to be diagnosed before turning 65. This equates to roughly 70,800 people, according to Dementia UK.
People aged between 45 and 50 with AF were found to be more than three times as likely to develop dementia compared to their peers without the heart condition.
The researchers believe this discovery could confirm the role of AF as a “primary pathogenic factor” in the development of dementia.
Initially, they said: “Atrial fibrillation is a risk factor for stroke and stroke is a risk factor for dementia.”
However, when they factored in stroke patients, they found that AF patients without a stroke on their record were still more likely to develop dementia and had the highest risk of early-onset dementia.
They concluded: “Other mechanisms must be involved in the increased risk of dementia among AF patients. These mechanisms may include silent strokes – meaning those that showed no clinical symptoms and can only be diagnosed with CT scan or MRI – and also microinfarcts, and microbleeds.”
The experts emphasised the need for further research into this area, as well as how managing AF in younger patients could impact the risk of dementia.