Researchers found that patients with different types of mitochondrial disease have higher rates of headaches compared to the general population. Tension-type headaches (TTH) were more frequent than migraines among this patient population, the study found.
The study, “Prevalence of Headache in Patients With Mitochondrial Disease: A Cross-Sectional Study,” was published in the journal Headache.
The study’s authors point out that the beta version of The International Classification of Headache Disorders (ICHD-3 beta) classifies a headache as a condition related only to MELAS patients (mitochondrial encephalopathy, lactic acidosis, and stroke), a type of mitochondrial disease, leaving out other types.
The researchers set out to find cases of headache in patients with other kinds of mitochondrial disease, notably chronic progressive external ophthalmoplegia (CPEO), an eye disease, and myoclonic epilepsy with ragged red fibers (MERRF), a type of epilepsy. They also looked at the kind of mutations patients had in their mitochondrial genes and at their genetic backgrounds.
The study included 42 participants. The majority of patients had CPEO (33 patients, or 79%), while MELAS was present in seven patients (17%), and MERRF in two (4%).
Of the 42 patients included in the study, 29 (70%) had headaches. TTH was present in 16 patients (38%). Migraine and probable migraine were identified in 12 out of 42 patients (29%). Two different headache types were identified in nine patients (21%).
The highest rates of headaches were identified in MELAS patients (86%). In patients with CPEO, headache was diagnosed in 21 (64%).
The majority of patients (62%) had headaches lasting less than four hours. Only five patients reported a headache lasting between four hours and three days. None of the patients reported headaches lasting more than three days. The frequency of headaches ranged from once per month to 20 per month in all patients with diagnosed headaches, with 70% reporting one to four episodes per month.
“The high rate of patients with probable migraine (duration shorter than 4 h) can be attributed to the fact that this migraine is part of the mitochondrial disease. Obviously, the duration of attacks in patients with migraine and mitochondrial disease is shorter than in patients with migraine without mitochondrial disease,” the authors wrote.
“The data also show that the current International Classification of Headache Disorder exclusively focused on MELAS syndrome does not consider the broader spectrum of mitochondrial diseases,” they added.
“The proposed vasculopathy [blood vessel disease] as a cause of headache in MELAS patients is questioned because vasculopathy is not a major ﬁnding in other mitochondrial syndromes with similar high frequency of headache. This supports the notion that impaired mitochondrial metabolism is, rather than vasculopathy, linked with headache,” they concluded.