Comparison of generalized and localized hyperalgesia in patients with recurrent headache and fibromyalgia

Objectives: Research suggests that dysregulated pain modulation may play an important role in recurrent headaches and fibromyalgia syndrome (FMS). The primary objective of this study was to investigate algesic responses in lo calized cervical and pericranial regions (ie, headache-specific areas) and distal locations (ie, trochanter and gluteal) in patients with primary head aches (tension-type and migraine). The headache patients' algesic responses were compared with those of a sample of patients with musculoskeletal pain who report generalized hyperalgesia, or FMS. Methods: Seventy patients wit h mixed headache diagnoses and 66 patients with FMS underwent a standardize d examination of generalized hyperalgesia based on American College of Rheu matology criteria. Results: Twenty-eight of the 70 headache patients report ed the presence of widespread TP pain, suggesting generalized hyperalgesia. Headache diagnosis was unrelated to the presence or absence of generalized hyperalgesia. The subset of headache patients with generalized hyperalgesi a did not differ from the FMS patients in pain sensitivity in the cervical and pericranial areas. Regression analyses revealed that pressure pain sens itivity was significantly related to self-reported pain only in the headach e patients with generalized hyperalgesia. Conclusions: These results sugges t that extensive dysregulation in pain modulation is important for a substa ntial minority of recurrent headache patients, who seem to be quite similar to FMS patients. Differential treatment planning targeting generalized hyp eralgesia may be useful in treating headache patients exhibiting generalize d hyperalgesia more effectively.