The rate of deaths from myocardial infarction in England has halved over the past decade, new research shows. Authors of the study, published online today on bmj.com, found that roughly half of the improvement was explained by a reduction in the overall rate of heart attacks, and half by an improvement in survival.
Researchers from the University of Oxford analysed national hospital and mortality data on 840,175 men and women in England who between them suffered 861,134 acute MI events over the nine years between 2002 and 2010. They examined the change in the overall rate of MIs over that period, and in the proportion of MIs that were fatal.
The overall decline in death rate from MI between 2002 and 2010 was 50% for men and 53% for women. A reduction in the overall rate of MIs, by about a third, accounted for just over half of the decline in total death rates (57% for men and 52% for women), with improved 30-day survival from MI accounting for the remainder of the decline (43% for men and 48% for women).
However, the authors found substantial variation by sex, age and geographical region in the relative contributions of event rate and case fatality to the reduction in deaths from MI – the greatest improvements were seen in 65-74-year-old men and women.
In fact, they said: “The annual declines in event rate were not statistically significant for men and women aged 30-54 and 85 and older, which raises the possibility that there was no real improvement in the rate of occurrence of acute myocardial infarction in these age groups over the past decade in England.” They suggest that rising rates of obesity and diabetes might contribute to a levelling of event rates in younger people; and that the lack of a decline in older people might result from changes in diagnostic criteria, or a shift in the presentation of disease from middle to old age.
Of all 311,419 fatal events, 70% were sudden deaths from acute MI i.e. with “no linked hospital admission for acute myocardial infarction in the previous 30 days”.
Author Professor Peter Weissberg, medical director of the British Heart Foundation – which partly funded the study – said: “This impressive fall in death rates is due partly to prevention of heart attacks by better management of risk factors such as smoking, high blood pressure and cholesterol and due partly to better treatment of heart attack patients when they reach hospital.”
He told BBC Radio 4’s Today programme that resuscitation should be more widely taught. He said: “Far too many heart attack victims still die from a cardiac arrest before medical help arrives. Many of these deaths could be prevented by rapid cardiopulmonary resuscitation. Our message is simple: hands-only CPR, as shown by Vinnie Jones, could save many more lives in the future.”