Risk Factors in Stroke Due to Cerebral Infarction

Abstract

In 1968 the Council on Cerebrovascular Disease of the American Heart Association authorized the appointment of a subcommittee to produce a statement concerning "risk factors for Stroke." After working for over a year the Subcommittee reported that, because of inadequate data concerning "all or several of the factors," they had been unable to produce a statement satisfactory to each Subcommittee member. Some were reluctant to set down a policy statement until every loophole was plugged--a task made extraordinarily difficult by the complexity of Stroke and the fact that prospective studies of large population groups are necessary for the acquisition of some needed data. Another problem was that of interpreting the phrase risk factors. Does this phrase imply that eliminating or minimizing a "risk factor" (for example, maintaining successful control of hypertension) automatically reduces the risk of Stroke for that individual? This therapeutic consideration may await an answer for years, although it must be admitted that the term "risk factors for Stroke" does suggest that careful treatment of one or several risk factors can help to prevent Stroke. In any event, the Subcommittee was admonished by its chairman, Dr. William Kannel, to consider the task a never-ending one; that data are now available indicating that certain phenomena are more commonly followed by Stroke and that these phenomena (culprits) should be publicly identified as elements or risk factors for Stroke. The Subcommittee decided to work first with the profile of the candidate at risk of a cerebral infarction--and so state. The Subcommittee realistically writes: "Any statement arrived at will be subject to periodic revision as more information is accumulated!" Obviously, new data may make changes necessary! Under Dr. Kannel's talented and dedicated leadership the Subcommittee produced the statement which follows.