Clinicians and health policy makers are demanding evidence of utility and cost-effectiveness for interventions previously justified by clinical judgement and convention alone. This is particularly true for management of cerebrovascular disease where both the interventions and the diseases are expensive. An effective investigator in this area must combine clinical with expertise in study design and quantitative methods. Accordingly, the overall objective of this proposal is to produce a program of study, combining didactic teaching, mentoring, and clinical studies, to allow Dr. Johnston to develop the skills necessary to independently perform rigorous epidemiological and health systems research in cerebrovascular disease. The skills will include study design, database management, development of prediction rules, cost- effectiveness analysis, and technical methods in multivariable analysis. Studies on the acute outcome of patients with transient ischemic attacks (TIAs.) will form the vehicle of this training. TIAs are important warning signs of stroke, with 15 percent of stroke patients previously experiencing a TIA. Little is known about risk factors for stroke and treatment effectiveness in acute TIA patients, leading to tremendous variability in clinical practice. Establishing acute stroke risk factors after TIA is required to justify expensive therapeutic and diagnostic interventions, including hospital admission and anticoagulation, which are currently employed in many institutions. We propose a series of studies to evaluate the variables--demographic, diagnostic, and interventional--determining outcome in TIA patients presenting acutely to a managed care system. These studies will include: 1) a stroke-free survival analysis of a cohort of TIA patients presenting to acute care clinics and emergency rooms to examine the overall early risk of stroke and the demographic factors that modify that risk; 2) a nested case-control study to define additional risk factors for early stroke; 3) development of a prediction rule to identify patients at minimal (less than 1 percent) risk of early stroke after TIA; 4) a cost-effectiveness analysis of hospitalization for acute TIA patients. This research should provide important results for clinicians and policy makers, and foster Dr. Johnston's development as an independent researcher in cerebrovascular disease epidemiology and outcomes.
