Classification and Nature of Catathrenia - Catathrenia is classified as a parasomnia in the ICSD-2, but its classification is debated. - In the ICSD-3, catathrenia is included in the category of respiratory disorders. - Ongoing debate exists about the nature and classification of catathrenia.

Signs and Symptoms of Catathrenia - Catathrenia is not life-threatening. - Bed partners hear deep breaths, followed by a high-pitched squeak or groaning sound during exhalation. - The sounds occur exclusively during expiration and are interrupted during inspiration. - Patients usually sleep normally despite the sounds, but sleep partners may be disturbed.

Characteristics and Variability of Catathrenia - Vocal sounds in catathrenia are usually short or long vocalizations of the same letter, mainly [a], [e], or [o]. - Catathrenia sounds have harmonics and show regular patterns between nights. - The duration of the sound varies from 0.5 to 49 seconds. - Sound intensity ranges from 40dB to 120dB. - The onset time of the noises during the night varies. - Response to CPAP treatment depends on respiratory disorders. - Catathrenia typically occurs during REM sleep, but it may also occur during NREM sleep.

Epidemiology and Diagnosis of Catathrenia - Catathrenia was first described in 1983 and is considered rare. - Misdiagnosis can occur, and a video-polysomnography with audio recording is necessary for diagnosis. - Incidences of catathrenia range from 0.17% to 0.4%.

Research, Studies, and Awareness of Catathrenia - Research has been conducted on the acoustic characteristics of catathrenia and its comparison to snoring. - Polysomnographic studies have monitored patients with catathrenia during sleep. - CPAP therapy has shown effectiveness in treating catathrenia. - Scientific articles have been published exploring different aspects of catathrenia. - Increased awareness and education about catathrenia can improve diagnosis and treatment.