OBJECTIVES: I. Determine the randomness of adrenocorticotropic hormone (ACTH) and cortisol secretion using approximate entropy in patients who have sustained a head injury.

II. Determine the correlation between randomness of ACTH and cortisol secretion and stages of sleep in these patients.

PROTOCOL OUTLINE: Patients are stratified according to type of injury (closed head injury due to trauma vs vascular accidents). Patients are admitted two times for overnight assessment.

Admission 1: Patients receive cosyntropin IV. Blood is drawn at 30 and 60 minutes after IV infusion. Patients receive oral metyrapone before sleep. A sham sleep study is conducted through the night and patients' blood is drawn in the morning.

Admission 2: At least 2 weeks after admission 1, patients return for an overnight admission. Starting in the evening, blood is drawn every 15 minutes for 12 hours. A sleep study is conducted through the night.

PROTOCOL ENTRY CRITERIA:

--Disease Characteristics--

Patients who have sustained head injury

Closed head injury from trauma OR

Vascular accidents like strokes and hemorrhages

--Prior/Concurrent Therapy--

Endocrine therapy: No concurrent cortisol replacement

Other: No blood donation during and for 1 month after study

--Patient Characteristics--

Hematopoietic: Hemoglobin normal

Other:

• No hypopituitarism
• No body mass index of 28 or greater
• Not pregnant or nursing
• Must have normal menstrual cycles
• No severe mental impairment
• Must not require legal guardian