The patient’s family history, medical history, and social and environmental history may provide information that clarifies the cause of an ischemic or hemorrhagic cerebrovascular event (Table 3-1). Familial risk factors for ischemic stroke have been difficult to define with certainty, although hypertension, systemic atherosclerosis, diabetes mellitus, and hyperlipidemia have at least some hereditary predisposition in many patients. A family history of ischemic stroke and formation of arterial or venous thromboses should be noted (see Chapter 23 regarding inherited stroke syndromes). In patients with subarachnoid hemorrhage or intracerebral hemorrhage, one should ask about a family history of intracranial hemorrhage, saccular aneurysm, arteriovenous malformation, cavernous malformation, polycystic kidney disease, connective tissue disorders, and bleeding disorders.

A comprehensive medical history should also be obtained. Previous cerebrovascular events of either ischemic or hemorrhagic type should be recorded. Because the presence of systemic atherosclerosis is a risk factor for cerebrovascular atherosclerosis, one should ask about previous myocardial infarction, angina, and claudication of extremities. A history of hypertension, diabetes mellitus, or hyperlipidemia is also an important risk factor for atherosclerosis. Other medical disorders that may be relevant for ischemic stroke are cardiac arrhythmias, valvular heart disease, connective tissue disorders, obstructive sleep apnea, and coagulopathy of both thrombotic and hemorrhagic subtypes. Previous head or neck trauma or radiation therapy also should be noted. For ischemic or hemorrhagic strokes, use of antiplatelet agents, anticoagulants, fibrinolytic therapies, estrogen supplements, dietary aids or appetite suppressants, decongestants, and herbal medications should be recorded.