by Michelle Rizzo

Last Updated: 2008-04-24 16:58:34 -0400 (Reuters Health)

NEW YORK (Reuters Health) – Headache associated with acute stroke generally starts on the first day of the stroke and tends to be continuous, according to a study published in the April issue of Cephalalgia. In more than half of the study patients, it also appears to be a re-activation of a previous primary headache.

"Headache is frequent in the setting of acute stroke, but many of its characteristics remain to be reliably described," Dr. A. Verdelho and colleagues from the University of Lisbon, Portugal, write. Previous studies have reported a wide variation in prevalence, a higher frequency associated with hemorrhagic stroke, and various areas of pain.

In the current study, the researchers describe the characteristics, duration, evolution, and type of headache associated with stroke in 124 patients, 61% with ischemic and 39% with hemorrhagic stroke. The patients’ median age was 58 years.

Patients consecutively admitted to a stroke unit were interviewed daily from stroke onset until day 8 using a validated headache questionnaire. Headaches were classified according to the International Headache Society classification.

Headache started on the first day of stroke in 107 patients (86%) and the mean headache duration was 3.8 days. Headaches were more often continuous and were more severe on the first day. The headache was more often bilateral and located in the anterior cranial region.

The most frequently described quality was pressure and the most frequent type of headache met the criteria for tension-type (61%). Eleven percent of headaches could not be classified using the IHS criteria.

Overall, 40% of patients who reported headache also experienced nausea and vomiting. Headache severity increased with cough and with movement.

Previous primary headache was documented in 71 patients. Reactivation of previous headache was documented in up to half of the patients.

"One of the most interesting findings of our study is that stroke can reactivate previous life-time headache," Dr. Verdelho said in an interview with Reuters Health. "Half of our cohort (that had previous headache) had a similar headache with stroke," she explained.

"So in these patients headache seems to be an entity that is reactivated by any brain insult and not specific for stroke," the author noted. "By the contrary, continuous headache in patients without previous headache is probably a very useful symptom of brain lesion, and the IHS classification was difficult to use in these headaches."

"I think we now have a better understanding of headache characteristics in the setting of acute stroke, and this fact is very useful in clinical practice. For instance, we have a prognosis of headache itself (in the setting of acute stroke)," Dr. Verdelho said.

Cephalalgia 2008;28:346-354.

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