AFib (IMAGE) Intermountain Medical Center Caption A new study has found that dementia rates increase when anticoagulation treatment is delayed for patients with atrial fibrillation, the most common heart arrhythmia in the world that affects more than 2.7 million American adults. Credit Intermountain Medical Center Heart Institute Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.