In the described patient with obesity and daytime fatigue, which factor most contributes to the risk of obstructive sleep apnea?

In the described patient with obesity and daytime fatigue, which factor most contributes to the risk of obstructive sleep apnea?

• A. Smoking
• B. Alcohol
• C. Age
• D. Obesity

Answer: (D)

Obesity is the strongest factor increasing the risk of obstructive sleep apnea because excess fat around the neck and pharynx narrows the upper airway and makes it more prone to collapse when the airway muscles relax during sleep. This mechanical narrowing, combined with reduced lung volumes and obesity-related inflammation, leads to more frequent apneas and hypopneas and, consequently, daytime fatigue. Other factors can contribute—smoking irritates airways, alcohol relaxes the throat muscles, and age can slightly reduce muscle tone—but none are as impactful on airway collapsibility as obesity. So, in the described patient, obesity best explains the elevated risk.

Obesity is the strongest factor increasing the risk of obstructive sleep apnea because excess fat around the neck and pharynx narrows the upper airway and makes it more prone to collapse when the airway muscles relax during sleep. This mechanical narrowing, combined with reduced lung volumes and obesity-related inflammation, leads to more frequent apneas and hypopneas and, consequently, daytime fatigue. Other factors can contribute—smoking irritates airways, alcohol relaxes the throat muscles, and age can slightly reduce muscle tone—but none are as impactful on airway collapsibility as obesity. So, in the described patient, obesity best explains the elevated risk.