Decreased pain detection and tolerance thresholds in chronic tension-type headache

Objective: To study nociceptive processing in patients with chronic tension-type headache. Methods: Forty patients with chronic tension-type headache and 40 healthy controls were examined. Pericranial tenderness was recorded by manual palpation, pressure pain detection and tolerance thresholds were recorded with an electronic pressure algometer, and the relative (pain detection minus sensory detection) electrical pain threshold was recorded with a constant current stimulator. Results: Patients were considerably more tender than controls at all the locations examined by manual palpation (P<.001). Pressure pain detection and tolerance thresholds recorded in the finger were significantly lower in patients than in controls (P<.001). A nonsignificant similar trend was observed in the temple (P less than or equal to.12). Detection and tolerance thresholds were decreased to a similar degree in patients compared with controls, and pain thresholds recorded in the finger and in the temple were highly correlated (r=.84, P<.001). The relative electrical pain threshold recorded at the labial commissure was significantly decreased in patients compared with controls (r=.03). All of the examined pain thresholds were significantly correlated to the pericranial tenderness recorded by palpation (r=-.35 to -.53, P less than or equal to.03). Conclusion: The present finding of a general hypersensitivity to pain stimuli in chronic tension-type headache indicates that central factors play an important role in the pathogenesis of this disorder.