The exact cause of atrial fibrillation is unknown, but it's more common with age and affects certain groups of people more than others.


It's also associated with other medical conditions, including:

However, not everyone with atrial fibrillation has one of the conditions above. It can sometimes affect people who are physically very fit, such as athletes.

When no other conditions are associated with atrial fibrillation, it's known as lone atrial fibrillation.


Certain situations can trigger an episode of atrial fibrillation, including:

  • drinking excessive amounts of alcohol, particularly binge drinking
  • being overweight (read about how to lose weight)
  • taking illegal drugs, particularly amphetamines or cocaine
  • smoking 

Page last reviewed: 18/05/2015

Next review due: 01/05/2018