Patients with a mitochondrial disease called MELAS syndrome have a high rate of obstructive sleep apnea — a condition where breathing repeatedly stops and starts during sleep — and poor sleep quality that highlights the need for patients with mitochondrial disease to be seen by a sleep specialist, according to a recent study published in the journal Sleep and Breathing.
In mitochondrial diseases, the mitochondria — the “power houses” of our cells — do not work properly. This means the body may not have enough energy, and organs like the heart, muscles and brain may not work as well as they should.
Although this study focused on one specific mitochondrial disease, MELAS syndrome (mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes), the findings may also be relevant to people with other mitochondrial conditions, such as thymidine kinase 2 deficiency (TK2d). More research is needed to understand whether TK2d is linked to similar sleep problems.
“This work reinforces the need for evaluation of patients with mitochondrial disease by a sleep specialist, as well as carrying out studies aimed at diagnosing possible sleep disorders, which could modify the treatment and quality of life of these subjects,” the researchers said.
Read about TK2d signs and symptoms
MELAS is a mitochondrial disease passed down from the mother. It can cause stroke-like episodes, seizures, muscle weakness, headaches, hearing loss, memory problems and diabetes.
The study included 18 people with MELAS. Seven patients had detailed overnight sleep testing (a sleep study that records breathing, brain activity and movement), while 11 patients’ past records were reviewed.
Obstructive sleep apnea was seen in 83% of all patients and in 100% of those who had full sleep testing. Many patients had poor sleep. On average, they took longer to fall asleep and woke up often during the night.
Patients commonly reported insomnia, snoring, daytime sleepiness, morning headaches and restless legs symptoms.
Limitations of the study included a small number of patients and no comparison group.
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