catathrenia
nocturnal groaning

It does not, however, include catathrenia's characteristic breath holding spells.

Catathrenia: "para-somnia or uncommon feature of sleep disordered breathing?"

There are a few other similarities amongst catathrenia sufferers that have not yet been studied properly:

Furthermore, there are catathrenia sufferers who have not seen improvement with CPAP, upper airway surgery, or oral appliance.

While a CPAP machine successfully treats catathrenia as defined by Dr. Guilleminault, there is debate whether he has confused catathrenia with expiratory snoring.