Contrariwise, certain manifestations of stroke may be incorrectly interpreted as evidence of some other neurologic disorder. Headache, at times severe, often occurs as a prodrome of a thrombotic stroke or subarachnoid hemorrhage; unless this is appreciated, a diagnosis of migraine may be made. Dizzy spells, vertigo, vomiting, or brief intermittent lapses of equilibrium as a result of vascular disease of the brainstem may be ascribed to vestibular neuritis, Ménière disease, Stokes-Adams syncope, or gastroenteritis. A detailed account of the attack will usually avert this error. A strikingly focal monoplegia of cerebral origin, causing only weakness of the hand or arm or foot-drop, is not infrequently misdiagnosed as a peripheral neuropathy or plexopathy.
Epidemiology of Stroke
Stroke assumes importance both because of its high rate of mortality and the residual disability that it causes. Stroke, after heart disease, cancer, and accidents is among the most common cause of death in the United States. Every year there are approximately 700,000 cases of stroke in the United States—roughly 600,000 ischemic lesions and 100,000 hemorrhages, intracerebral or subarachnoid—with 175,000 fatalities from these causes combined. Since 1950, coincident with the introduction of effective treatment for hypertension and hyperlipidemia, there has been a substantial reduction in the frequency of stroke. Both sexes have shared in the reduced incidence. During this period, the incidence of coronary artery disease and uncontrolled hypertension also fell significantly. By contrast, there has been no change in the frequency of aneurysmal rupture. In the last two decades, according to the American Heart Association, the mortality rate from stroke has declined by 12 percent, but the total number of strokes may again be rising.
The burden of stroke has far wider implications when viewed from an international perspective. Cerebrovascular disease is estimated to account for 7.8 million deaths yearly throughout the world and represents about 13 percent of all causes of death. In developed countries, stroke mortality is only surpassed by cardiac ischemic diseases and close to equivalent to the cancers collectively (mainly lung cancer) in the Global Burden of Disease study. Stroke remains among the five leading causes of death across every income group in most countries in the last comprehensive review by the World Health Organization. The cumulative lifetime risk for 195 countries between 1990 and 2016 has been estimated to be 18 percent for ischemic stroke and 8 percent for hemorrhagic stroke. Strokes cause significant physical, emotional, and cognitive disabilities among survivors, accounting for 3.6 percent of the total disability-adjusted life years (DALYs) and thus placing stroke within the 10 leading causes of disability irrespective of the development status of countries (The 203 Global Burden of Disease for stroke can be found in the article by Feigen et al).