Does the incidence, severity, or case fatality of stroke vary in southern England?

STUDY OBJECTIVES

To determine differences in incidence and case fatality of stroke in district health authorities with differing standardised mortality ratios (SMR) for stroke in residents aged under 65 years in whom death from stroke is considered 'avoidable'.

DESIGN

Registration of first ever strokes in three district health authorities. Patients were assessed and followed up over one year by one of three observers.

SETTING

West Lambeth, Lewisham and North Southwark, and Tunbridge Wells District Health Authorities in south east England.

PARTICIPANTS

Patients under the age of 75 years having a first ever in a lifetime stroke between 15 August 1989 and 14 August 1990.

MEASUREMENTS AND MAIN RESULTS

Age specific incidence rates and survival time from stroke to death. Severity was assessed in terms of the level of consciousness and the presence of speech, urinary, and motor impairment within the first 24 hours of the stroke. Altogether 386 strokes were registered. There was a significant difference in the incidence rate between district health authorities in those aged under 65 (p < 0.01). The overall case fatality was 26% at three weeks with no significant difference between the districts. Poor survival was associated jointly with increased age and with coma, incontinence, and swallowing impairment in the first 24 hours after a stroke.

CONCLUSIONS

The SMRs for stroke in those aged under 65 in these three health districts reflect the incidence of stroke. Case fatality at three weeks does not vary between these districts and consequently would not be a sensitive indicator of the quality of care. This also suggests that differences in services between the districts did not lead to changes in prognosis. In districts with high SMRs for stroke there is a need for further study and reduction of risk factors, thereby reducing the incidence and burden of stroke locally. This study provides a framework for assessing the needs for stroke prevention and treatment in both rural and urban areas without an elaborate protocol and detailed neurological assessment.