A retrospective study of 134 patients in a condition of prolonged unawareness state (that is, in coma for over 1 month) following brain trauma was conducted in order to identify prognostic factors. Eight easily evaluated parameters were found to be significant for predicting nonrecovery of consciousness. The following six features were present during the early posttraumatic phase (that is, during the 1st week after trauma): fever of central origin; diffuse body sweating; disturbances in antidiuretic hormone secretion; abnormal motor reactivity; respiratory disturbances; and diffuse nonneurological injuries. The first three features were manifestations of hypothalamic damage. Two factors, evident at a late phase following injury (after the 1st week posttrauma), namely late epilepsy and communicating hydrocephalus, were also significant in predicting nonrecovery.