Objective

To describe the prevalence and characteristics of sleep-disordered breathing (SDB) in a large cohort of patients with genetically confirmed mitochondrial diseases.

Methods

This is a prospective observational study performed at the Neurophysiopatology Unit of Fondazione Policlinico Universitario A. Gemelli IRCCS. All subjects had a defined mitochondrial disease and were investigated by full night polysomnography.

Results

103 consecutive patients were enrolled. SDB was demonstrated in 49 patients (47.6%). Regarding phenotypes, we found differences in distribution between the groups: patients affected by PEO with single or multiple mtDNA deletions frequently had obstructive apneas (50% and 43.8%) or REM-related hypoventilation when associated with m.3243A>G mutations (75%). Furthermore, a high percentage of subjects with MIDD and MERRF syndromes were characterized respectively by obstructive sleep apnea and REM-related hypoventilation. Differently from what is previously reported, central sleep apnea was rarely reported in our cohort.

Conclusions

SDB has a higher prevalence in MDs compared to general population-based data. Overall, these results suggest that patients characterized by a specific phenotype-genotype combination are most at risk of developing a specific subgroup of SDB. The early identification of this disorder is crucial in the management of these fragile patients.