Atrial Fibrillation Risk Factors: Who Is Most Vulnerable?

Atrial fibrillation (AF) risk is multifactorial. The CHA₂DS₂-VASc score stratifies stroke risk, but understanding etiologic risk factors guides prevention.

Non-Modifiable Risk Factors

• Age: Prevalence doubles each decade >50. >10% at 80+.
• Sex: Men higher incidence; women higher stroke risk at same CHA₂DS₂-VASc.
• Race: White > Black > Hispanic/Asian (partly due to survival bias).
• Genetics: Familial AF (10–15%); loci near PITX2, ZFHX3.

Modifiable Risk Factors (Strong Evidence)

• Hypertension (most common): LVH, LA enlargement, fibrosis. Target <130/80.
• Obesity (BMI ≥30): 50% increased risk. Weight loss reduces AF burden.
• Diabetes mellitus: Fibrosis, autonomic dysfunction.
• Sleep apnea (OSA): 2–4x risk. CPAP reduces recurrence post-ablation.
• Alcohol: "Holiday heart" (acute); chronic use → structural remodeling. Even 1 drink/day ↑ risk.
• Physical inactivity / Excessive endurance exercise: U-shaped curve.
• Smoking: Current smokers 1.5x risk; declines after cessation.

Cardiac & Medical Conditions

• Heart failure, CAD, valvular disease (mitral), post-cardiac surgery (30–40% incidence).
• Thyroid dysfunction (hyper > hypo).
• Chronic kidney disease.
• Inflammatory conditions (RA, SLE).

Medication Triggers

• Catecholamines, adenosine, dobutamine, theophylline, bisphosphonates (rare).

Prevention Strategy

Aggressive risk factor modification (weight loss, OSA treatment, alcohol reduction, BP control, exercise) reduces AF incidence, progression, and ablation failure rates. Upstream therapy is as important as rhythm control.