As a general statistic, the presence of AFib increases the risk of stroke about 5-fold.  As shown in the Figure, however, this depends again on the age of the patients.  On the left side of the Figure it can be seen that of all strokes, approximately 15% are associated with AFib^[122]; on the right, the chart shows that in patients who are aged >80 years, 36% of strokes are related to AFib.[123]

French WJ. Am J Med 2013; 126: 00-00.