How can central sleep apnea be distinguished from obstructive sleep apnea, and what common condition is it associated with?

• A. Central sleep apnea involves absence of respiratory effort; obstructive involves airway obstruction; commonly associated with heart failure or stroke.
• B. Central sleep apnea involves airway obstruction; obstructive has no respiratory effort; commonly associated with diabetes.
• C. Central sleep apnea is a daytime problem; obstructive is nocturnal; commonly associated with obesity.
• D. Central sleep apnea occurs with snoring; obstructive does not; commonly associated with asthma.

Answer: (A)

The main idea is how respiratory effort during sleep differentiates the two conditions. Central sleep apnea happens because the brain stops sending the signal to breathe, so both airflow and the chest/abdominal effort disappear during an apneic event. Obstructive sleep apnea, on the other hand, involves a physical blockage of the airway even though the person is trying to breathe, so there is ongoing respiratory effort but airflow is reduced or stops. This distinction is what you’d see on a sleep study: central events show little to no respiratory effort, while obstructive events show continued effort with blocked airflow. Central sleep apnea is commonly linked with conditions that affect breathing control or circulation, especially heart failure and, less often, stroke.