Altered brain functional connectivity in patients with tension-type headache

Objective: To evaluate whether patients with tension-type headache (TTH) exhibit abnormal brain functional connectivity compared to healthy controls.

Background: TTH is one of the most prevalent headache disorders throughout the world. The present study delves into brain functional connectivity in patients with TTH to enhance the understanding of its underlying pathophysiology.

Methods: A cross-sectional study was conducted, enrolling patients with TTH diagnosed in line with the International Classification of Headache Disorders, 3rd edition beta criteria and a cohort of healthy controls (HCs). We used four metrics-global brain functional connectivity, functional connectivity, Granger causality analysis, and dynamic functional connectivity-to evaluate alterations of functional connectivity patterns in patients with TTH from both static and dynamic perspectives. Furthermore, correlational analyses were performed to explore the relationships between abnormal brain activities and clinical characteristics.

Results: A total of 33 patients with TTH (mean age = 42.3; 13 males/20 females) and 30 HCs (mean age = 37.1; 13 males/17 females) were included in the current study. Compared to HCs, patients with TTH showed altered global brain functional connectivity in the right dorsolateral superior frontal gyrus (SFGdor, t = 4.60). Abnormal functional connectivity was also detected between the right SFGdor and the right superior temporal gyrus (t = 4.56). Furthermore, the right SFGdor exhibited altered information flow with several brain regions, including the left precuneus (t = 5.16), right middle temporal gyrus (MTG, t = 4.72/-4.41), right inferior temporal gyrus (t = 4.64), right caudate nucleus (t = 4.09), and right thalamus (THA, t = -4.04). In terms of dynamic functional connectivity, disconnection was observed between the right SFGdor and the right MTG (t = -3.10), right Rolandic operculum (ROL, t = 3.60), left opercular inferior frontal gyrus (t = -3.48), and left medial superior frontal gyrus (t = -3.00). In addition, the correlation analyses revealed that activities in the MTG (r = 0.48), THA (r = -0.38), and ROL (r = 0.36) were significantly correlated with disease duration, while THA activity was associated with Visual Analogue Scale scores (r = 0.50).

Conclusions: This study revealed alterations in both static and dynamic brain functional connectivity in patients with TTH within regions implicated in sensory perception, emotional processing, cognition, and pain regulation. These results may promote the understanding of the neural networks involved in TTH and potentially inform future therapeutic approaches for the condition.