Distinguishing Sleep Groaning from Snoring
Snoring is a common sleep disturbance. Perhaps half of all people snore sometimes, and about a quarter snore regularly. However, catathrenia is much less common, occurring in 0.17% to 0.4% of people who visit sleep clinics (17-40 people out of 10,000). However, it might be more common in the general population. Almost all people with catathrenia find out about it because someone else points it out to them. People without a sleep partner might not discover their catathrenia.
Unlike sleep apnea, catathrenia affects men and women equally. It often affects young people, including children, and doesn’t seem to increase with age.
Catathrenia and snoring are both sounds that people make during sleep. Snoring can come in many forms, so it can sometimes sound like a groan. However, you can distinguish catathrenia from snoring because catathrenia occurs only while exhaling, but snoring can occur during both inhalation and exhalation.
The name catathrenia comes from the Greek words kata (below) and threnia (lament). The name was chosen because the sleep groans often have a monotonous, sad sound. However, they can also sound sexual in nature, which can make people embarrassed to bring it up. They might not want to talk to their partner or doctor about it because they fear the sounds are related to sexual dreams.
However, it does not seem that the sounds are related to any particular dreams. Although sleep groaning sometimes occurs during REM sleep (when most dreaming occurs), sleep groaning can actually happen at any stage of sleep.