Catathrenia, or nocturnal groaning, is a relatively rare and undocumented parasomnia, in which the subject groans during their sleep - often quite loudly. This disorder is long lasting, and seems to occur nightly in most people. It can occur during any stage of sleep, but seems to happen with the most frequency during REM or deep sleep. It can come and go during the night, and restless sleep with a lot of tossing and turning may actually ward it off, as it’s been documented that subjects who move around a lot experience breaks in the groaning after shifts in position. This also may tie into the contention that it occurs mostly during deep sleep.
Contrary to snoring which occurs during inhalation, groaning occurs during exhalation, and one groan can last as long as 30 seconds. The groans are usually succeeded by a snort or sigh at the end. Groaning usually comes and goes in stretches, with any one stretch lasting as long as an hour.
Groaning is not related in any way to sleeptalking. It has also shown no connection to general breathing problems or sleep related breathing problems, any abnormal brain activity or mental disorders, or any other sleep related disorders in general. What causes the groaning in people is still a relative mystery.
The groaning bears no connection to any mental anguish or dream state the person may be in, a common misconception. Though people in these states have been known to make small groaning noises, they are not related to catathrenia. Other sleep related groaning type noises that could be misinterpreted as catathrenia include some types of snoring, and the moaning noises that may be made during an epileptic seizure. People with catathrenia usually have calm facial expressions and peaceful sleep despite the noise. The easiest way to distinguish snoring from catathrenia is that snoring occurs while inhaling, and groaning while exhaling. A careful examination of a partner’s breathing pattern in conjunction with the noises should be able to clarify which of the two it is.
Most people with catathrenia are not bothered by their own groaning, and will not rouse due to it, though it may be quite loud and potentially sleep disturbing to a bed partner. Most people with catathrenia will not even be aware of the disorder unless told by a bed partner, and likely will not believe the partner when told. Groaning appears to affect more males than females, and can start at any age. It appears in most cases that the groaning remains for many years. Subjects may wake up with sore throats the next morning, depending on the extent of the groaning the night before.
As the catathrenia has little to no effect on a person’s sleeping quality, and bears no connection at present to any other disorders that may be causing it, or that it may lead to, it may be unnecessary to have it looked into. If the disorder is causing distress to a bed partner, the easiest course of action may be for the partner to wear ear plugs while sleeping.
There is limited data on effective treatment plans, but there is some evidence to suggest that positive airway pressure (PAP) may be beneficial in limiting the frequency and ferocity of catathrenia.