Atrial fib rillation is one of the most common heart rhythm disorders - up to 6.5 million people in the US alone are affected. The condition is quite dangerous, as it promotes the formation of thrombi in the body which, when they reach the central nervous system, can lead to stroke. However, atrial fibrillation does not only lead to this risk - it can also exacerbate the possibility of developing dementia.

The South Korean researchers who came to this conclusion based their work on information from more than 260,000 patients aged 60 and over. At the time the analyses began, the subjects were not suffering from either atrial fibrillation or dementia disorders.

The duration of follow-up was nine years. During this period, slightly more than 10,000 of all subjects developed atrial fibrillation. In turn, among those patients who developed this heart rhythm disorder, 24.4 per cent also developed dementia disorders. Interestingly, in the group of patients who did not develop atrial fibrillation, 14.4 per cent developed dementia.

Given these data, it is fairly easy to conclude that atrial fibrillation may to some extent exacerbate the risk of dementia. However, there did appear to be a protective factor against dementia in patients with atrial fibrillation, as it was apparent that those who took anticoagulants (compared with those who did not) had a lower risk of comorbid dementia with atrial fib rillation.