CORONARY EVENT AND CASE-FATALITY RATES IN AN ENGLISH POPULATION - RESULTS OF THE OXFORD MYOCARDIAL-INFARCTION INCIDENCE STUDY

Objectives-To determine coronary event and case fatality rates in an E nglish population aged less than 80 years in Oxfordshire, and to compa re these rates with those reported by the UK monitoring trends and det erminants of cardiovascular disease (MONICA) centres in Scotland and N orthern Ireland and those ascertained in Oxfordshire in 1966-67. Desig n-A population wide surveillance study conducted in 1994-95 using pros pective and retrospective case ascertainment. Setting-A resident popul ation in Oxfordshire of 568 800. Subjects-Patients with suspected myoc ardial infarction or coronary death. Outcome measures-A diagnosis of d efinite or possible myocardial infarction or coronary death using WHO MONICA diagnostic criteria based on symptoms, electrocardiograms, card iac enzymes, necropsy findings, and past medical history. Results-The annual rate for a first or recurrent coronary event per 100 000 popula tion aged less than 65 years in 1994-95 was 273 for men and 66 for wom en after age adjustment to a standard world population. Rates in the a ge group 65-79 years were 1350 for men and 677 for women. Between 1966 -67 and 1994-95, the age standardised event rate in the age group 30-6 9 years decreased significantly by 33% (95% confidence interval (CI) 4 4 to 21) in men, and there was a nonsignificant reduction of 8% (95% C I -33 to 17) in women. The age standardised 28 day case fatality rates also decreased significantly by 28% (95% CI 41 to 15) in men and by 3 2% (95% CI 55 to 9) in women. Conclusions-The coronary event rate in O xfordshire was much lower than rates reported by MONICA centres in Gla sgow and Belfast, and similar to rates reported by MONICA centres in F rance and northern Italy. The substantially lower event rate accounts for lower coronary heart disease mortality in Oxfordshire than in Scot land and Northern Ireland. The reduced coronary mortality in this regi on is attributable to declines in coronary event and case fatality rat es.