Role of blood pressure in stroke.

Abstract

To the Editor.— My comments concern the article by Kannel et al, entitled, Epidemiologic Assessment of the Role of Blood Pressure in Stroke ( 214: 301, 1970). According to the data presented there is a close parallelism between an elevated systolic or diastolic pressure as measured at an initial examination and the development of brain infarction in the subsequent 14 years followup. I could find no data to show that the people involved had sustained hypertension on biennial examinations. No data rule out the possibility that the worse the presenting hypertension the more antihypertensive treatment, with the consequence that it would be these individuals who would suffer the greatest sleeping cerebral hypotension with subsequent sludging-infarcts. I would like to know what fraction of brain infarctions occurred while the patients were asleep.