Patients with chronic cluster headache may show reduced activity energy expenditure on ambulatory wrist actigraphy recordings during daytime attacks

Structured Abstract Objective To investigate the changes in activity energy expenditure throughout daytime cluster headache attacks in patients with chronic cluster headache, and to evaluate the usefulness of actigraphy as a digital biomarker of cluster headache attacks. Background Cluster headache is a primary headache disorder characterized by attacks of severe to very severe unilateral head pain with ipsilateral cranial autonomic symptoms and/or a sense of restlessness or agitation. We hypothesized increased activity energy expenditure from hyperactivity during attacks measured by actigraphy. Methods An observational study including patients with chronic cluster headache was conducted. During 21 days, patients wore an actigraphy device on the non-dominant wrist and recorded cluster headache attack-related data in a dedicated smartphone application. Accelerometer data was used for the calculation of activity energy expenditure before and during daytime cluster headache attacks that occurred in ambulatory settings, and without restrictions on acute and preventive headache treatment. We compared the activity and movements during the pre-ictal, ictal, and postictal phases with data from wrist-worn actigraphy with time-concordant intervals during non-headache periods. Results Four patients provided 34 attacks, of which 15 attacks met the eligibility criteria for further analysis. In contrast with the initial hypothesis of increased energy expenditure during cluster headache attacks, a decrease in movement was observed during the pre-ictal phase (30 min before onset to onset) and during the headache phase. A significant decrease (p<0.01) in the proportion of high-intensity movement during headache attacks, of which the majority were oxygen-treated, was observed. This trend was less present for low-intensity movements. Conclusion The results of our analysis may shift the initial hypothesis for future research towards a decrease in activity energy expenditure during the pre-ictal and headache phase of daytime attacks in patients with chronic cluster headache under acute and preventive treatment in ambulatory settings.