Natural History of Stroke in Rochester, Minnesota, 1955 Through 1969: An Extension of a Previous Study, 1945 Through 1954

Abstract

This study has attempted to identify all patients in the population of Rochester, Minnesota, who had stroke during the period 1955 through 1969, and to determine the course and survival of patients who have had stroke. Cerebral infarction from all causes, including embolic infarction, accounted for 79% of all strokes. Intracerebral hemorrhage accounted for 10% of the cases, and subarachnoid hemorrhage accounted for 6%. The average annual incidence rate for the 15 years of the study was 164 per 100,000 population per year. The rates for all strokes and for cerebral infarction were significantly higher for men than for women, except in the youngest age group. After the end of an earlier study, 1945 through 1954, the average annual incidence rate for all strokes decreased in each succeeding five-year interval and reached 141 during the period 1965 through 1969. The decrease in rates is apparent for all strokes and for cerebral infarction, and is more apparent for women than for men. The prevalence rate on January 1, 1960, and January 1, 1965, of about 700 per 100,000 population was higher than the rate for January 1, 1970, reflecting decreasing incidence rates. A study of the functioning capacity of survivors of stroke after six months indicates that only 4% required total care and nearly 30% were functioning normally. Fifty-four percent had some neurological deficit that may have been benefited by rehabilitative care. Aphasia was an important residual incapacity in 10%. The first-year recurrence rate of stroke was 10%, and the five-year recurrence rate was 20%. Among patients with stroke who died, 38% died of the initial stroke, 10% of a subsequent stroke, and 18% of heart disease. During the 25-year period, 1945 through 1969, there has been a trend toward gradually increasing survival for cerebral infarction in this community.