Subarachnoid hemorrhage of unknown etiology: early prognostic factors for long-term functional capacity. Forty-one patients suffering subarachnoid hemorrhage (SAH) of unknown etiology were re-investigated at an average of 91 months after the bleed to determine functional capacity. Nineteen patients were performing at their previous level of work, five were employed part-time, and four could not work due to the SAH. Five patients showed a moderate disability in activities of daily living but were not dependent on help, one patient was severely disabled, and two had died. There was one rebleed. Early prognosis of an unfavorable outcome was possible on the basis of three clinical variables on admission: a history of hypertension, a Hunt and Hess grade of greater than II, and the presence of focal neurological deficits. In addition, the presence of an organic mental syndrome at discharge was identified as a predictive factor for reduced functional capacity later on. Other clinical variables in the acute stage, including sex, age, history of headache, interval between SAH and admission, impaired consciousness, and cognitive deficits, were not related to a limited functional level. Residual neurological deficits and the Glasgow Outcome Scale score on discharge were also not predictive of restrictions in global functions evaluated by means of the Karnofsky Performance Scale status at follow-up review. 