Which of the following is a risk factor for atrial fibrillation?

• A. Hypertension
• B. Hyperlipidemia
• C. Hypothyroidism
• D. Sleep apnea

Answer: (A)

Chronic high blood pressure leads to changes in the atrial structure and electrical properties that make atrial fibrillation more likely. The extra pressure and stretch from hypertension cause the left atrium to enlarge and develop fibrosis, which disrupts normal conduction and creates a substrate that supports rapid, disorganized atrial activity. This remodeling is a well-established pathway linking hypertension to AFib and helps explain why high blood pressure is such a common and important risk factor.

Among the other options, some can influence AFib risk in different ways—sleep apnea, for example, can also promote AFib through intermittent hypoxia and autonomic changes—but hypertension is the most consistently recognized and modifiable risk factor listed. Hyperlipidemia is more about atherosclerotic disease than direct atrial remodeling, and hypothyroidism is not a typical AFib risk factor (hyperthyroidism raises AFib risk more).