Which of the following is NOT a primary characteristic of obstructive sleep apnea?

In the context of obstructive sleep apnea (OSA), the primary characteristics include interruptions in breathing due to the relaxation of throat muscles during sleep. Therefore, statements about frequent awakenings, episodic gasping or choking, and daytime fatigue and sleepiness align with the clinical manifestations of this condition.

Regular periods of deep sleep are not characteristic of obstructive sleep apnea because the frequent disturbances and awakenings caused by apnea events prevent the individual from achieving adequate deep sleep. OSA sufferers typically experience fragmented sleep, which hinders their ability to reach the deeper stages of the sleep cycle, leading to reduced overall sleep quality. This fragmentation contributes to the other symptoms associated with OSA, such as excessive daytime sleepiness and fatigue, as well as the risk of awakening gasping for air.