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Pain sensitivity mediates the relationship between stress and headache intensity in chronic tension-type headache.

BACKGROUND
A central model for chronic tension-type headache (CTH) posits that stress contributes to headache, in part, by aggravating existing hyperalgesia in CTH sufferers. The prediction from this model that pain sensitivity mediates the relationship between stress and headache activity has not yet been examined.


OBJECTIVE
To determine whether pain sensitivity mediates the relationship between stress and prospective headache activity in CTH sufferers.


METHOD
Self-reported stress, pain sensitivity and prospective headache activity were measured in 53 CTH sufferers recruited from the general population. Pain sensitivity was modelled as a mediator between stress and headache activity, and tested using a nonparametric bootstrap analysis.


RESULTS
Pain sensitivity significantly mediated the relationship between stress and headache intensity.


CONCLUSIONS
The results of the present study support the central model for CTH, which posits that stress contributes to headache, in part, by aggravating existing hyperalgesia in CTH sufferers. Implications for the mechanisms and treatment of CTH are discussed.