THE PREVALENCE OF MULTIPLE-SCLEROSIS IN THE LEEDS-HEALTH-AUTHORITY

Objectives-To determine the prevalence of multiple sclerosis in the Le eds Health District. Methods-Multiple sources of case ascertainment we re used-namely, neurology departments, hospital episode statistics, ge neral practitioners, the Leeds branch of the Multiple Sclerosis Societ y, the West Yorkshire Multiple Sclerosis Therapy Centre, community phy siotherapists and occupational therapists, the Leeds Wheelchair Centre , and the Young Disabled Unit. Data collection was from retrospective analysis of hospital and primary care case records. A population based incidence register was established by prospectively registering all n ew patients with diagnoses of multiple sclerosis. Results-On prevalenc e day, 30 April 1996, 712 people with multiple sclerosis were identifi ed living in Leeds (population 732 061), giving a prevalence of 97/10( 5). The prevalence for definite and probable multiple sclerosis was 84 /10(5), and for suspected multiple sclerosis it was 13/10(5). The sex ratio of prevalent people with multiple sclerosis was 2.79 to 1 women to men. The mean age of prevalent cases was 51 years, the mean age at symptom onset was 34 years, and the mean duration of disease was 16 ye ars. Forty cases were prospectively reported as incident cases from 1 November 1995 to 1 February 1996. Conclusions-The prevalence of multip le sclerosis in Leeds was found to be similar to that in the south of the United Kingdom but lower than that in Scotland. There is no eviden ce of a latitudinal gradient of increasing prevalence of multiple scle rosis from the south to the north of England.