Follow-up of idiopathic thunderclap headache in general practice

Follow-up studies of idiopathic thunderclap headache (ITH) have found no su bsequent subarachnoid hemorrhage (SAH) or other serious neurological diseas e, but the effect on life-style has not been studied. To assess the long-te rm outcome of patients with ITH in general practice we prospectively follow ed 93 patients with an episode of ITH during 1988-1993, of whom 77 were ref erred to hospital. ITH was defined as a sudden, unusually severe headache t hat started within I min, lasted at least 1 h, and for which no underlying cause was found. These patients were treated in 252 general practices. Outc ome measures were subsequent SAH, subsequent headaches, absence from work, and diminished daily functioning. Patients were followed up by their genera l practitioner for a median of 5 years (range 1-10). Three patients died, a ll from nonneurological diseases. No subsequent SAH was diagnosed in any of the 93 patients. Recurrent attacks of ITH occurred in 8 patients, and 13 d eveloped new tension headache or migraine. Absence from work because of hea dache was recorded in 11 patients, and in the overall group 6 patients were dependent on welfare. In only one-half of patients (n=52) did the general practitioner judge the level of daily functioning to be similar to that bef ore the index episode of ITH. Thus, although no episodes of SAH occurred af ter ITH during long-term follow-up, one-half of patients with ITH had a low er level of daily functioning, and one-eighth had reduced working capacity, specifically because of headache.