[Breathing disorders during sleep in patients with dystrophic myotonia]

To analyze the results of nocturnal breathing parameters during sleep based on nocturnal pulse oximetry and to study of characteristics of external respiration in genetically confirmed patients with dystrophic myotonia (DM).

The subjects of the study were patients with genetically confirmed DM types 1 and 2 who were hospitalized in the neurological departments of the Republican Scientific and Practical Center for Neurology and Neurosurgery. The clinical picture of the disease, comorbidities, sleep questionnaires, laboratory tests, overnight pulse oximetry and spirometry were performed and analyzed.

There was a significant decrease in the main parameters of the spirogram, which reflect disturbances in the function of external respiration of a restrictive type, due to a decrease in the efforts of the respiratory muscles. A study of the respiratory parameters of the polysomnogram revealed a decrease in the average total level of blood oxygen saturation (SpO₂) and SpO₂ during the period of night sleep, minimum SpO₂, apnea/hypopnea index and desaturation index, which indicates a decrease in blood oxygen saturation during sleep and a predisposition to obstructive sleep apnea (OSA).

The results reflect the presence of frequent breathing disorders during sleep and external respiration parameters in DM patients. The identified changes are due to weakness of the respiratory muscles, as well as the muscles of the oropharyngeal zone, which is confirmed by the high probability of OSA according to the Berlin Questionnaire and a decrease in respiratory function parameters. Breathing disorders during night sleep in DM require timely diagnosis, monitoring of symptoms and, if necessary, their treatment due to the significance of their impact on the quality of life in DM patients.