A study published in Neurology, the official journal of the American Academy of Neurology, showed that cluster headaches and migraine have strong links to the circadian system, the internal clock regulating our biological functioning.

The data suggest that both headache types, particularly cluster headaches, are strongly circadian on several levels revealing the critical role of the hypothalamus in cluster headaches and migraine and raises concern over the genetics of triggers such as sleep disruptions.

The meta-analysis demonstrated that 71% of people suffering from Cluster headache had a specific circadian pattern of headache attacks. The attacks accelerated from late night to early morning and also during the spring season and winter. Cluster headache is known to be related to two important circadian genes and five out of nine genes that are responsible for causing the same. Patients with such headaches have greater levels of cortisol and lower levels of melatonin than the non-cluster headache patients

In addition, the study also found the presence of a circadian pattern in episodes among 50% of migraine sufferers. The migraine attacks peaked from latter in the morning to early hours in the evening. A a circadian low point was observed during night time. Two vital circadian genes were related to developing migraine. 110 out of 168 migraines related genes showed a circadian expression pattern. After a migraine attack melatonin levels were found to be significantly less.

These findings pave a way to support to the use of circadian-based treatments for headaches.

(Source: https://theprint.in/health/study-reveals-how-cluster-headache-migraine-connected-to-internal-clock-that-regulates-body-processes/1521807/