What is the average age of onset for atrial fibrillation (AF) in men and women?

Average Age of Onset for Atrial Fibrillation in Men and Women

The median age of onset for atrial fibrillation is approximately 75 years, with men developing AF earlier than women, though the overall number of men and women with AF is about equal. 1

Gender Differences in AF Onset and Prevalence

Age Distribution

• The prevalence of AF increases significantly with age:
  • 0.4-1% in the general population
  • Less than 0.1% in people under 40 years
  • Increases to approximately 8% in those over 80 years 1

Gender-Specific Patterns

• Men:

  • Higher age-adjusted prevalence than women 1
  • Prevalence has more than doubled from the 1970s to 1990s 1
  • 1.5-fold greater risk of developing AF than women after adjustment for age and predisposing conditions 2

• Women:

  • Prevalence has remained relatively constant over time 1
  • Approximately 60% of AF patients over 75 years are female 1
  • Tend to develop AF at a more advanced age than men 1

Demographic Distribution

The ALFA study (Etude en Activité Libérale sur la Fibrillation Auriculaire) provides valuable insights into the age distribution across different types of AF 1:

• Total AF population: median age 69 years
• Paroxysmal AF: median age 66 years
• Chronic AF: median age 70 years
• Recent-onset AF: median age 68 years

Risk Factors Influencing Age of Onset

Several conditions can influence the age of onset of AF:

1. Cardiovascular conditions:

   • Hypertension (increases risk 1.4-1.5 fold)
   • Heart failure (increases risk 4.5-5.9 fold)
   • Valvular heart disease (increases risk 1.8-3.4 fold)
   • Coronary artery disease 1, 2

2. Other medical conditions:

   • Diabetes (increases risk 1.4-1.6 fold) 2
   • Thyroid disease 1

3. Demographic factors:

   • Race: The age-adjusted risk of developing AF in blacks appears to be less than half that in whites 1

Lifetime Risk

The lifetime risk for developing AF is substantial:

• At age 40: 26.0% for men and 23.0% for women
• At age 80: 22.7% for men and 21.6% for women 3

Clinical Implications

The age of onset has significant implications for management and prognosis:

• The attributable risk for stroke associated with AF increases dramatically with age:

  • 1.5% at age 50-59 years
  • 23.5% at age 80-89 years 2

• Mortality risk:

  • AF is associated with approximately doubling of mortality in both sexes
  • This decreases to 1.5-1.9-fold after adjusting for associated cardiovascular conditions 2

Understanding the typical age of onset for AF (median 75 years) and its gender differences helps clinicians identify high-risk populations for screening and early intervention, potentially reducing the substantial morbidity and mortality associated with this common arrhythmia.