The British Medical Journal has published the results of a study that aimed to assess trends in long term survival in patients alive 28 days after myocardial infarction (MI) in the context of evidence based medical treatments.
The study was a population-based analysis of 4,451 consecutive cases of acute MI between 1984 and 1993 in Perth, Western Australia. The entire cohort was divided into three groups based on date of admission and analysed for all-cause and cardiovascular mortality.
There was a 7.6% absolute reduction in the risk of all-cause mortality when comparing the most recent cohort to the least recent. This improved survival remained after correcting for several variables including demographic factors, coronary risk factors and severity of disease. The difference was not apparent after adjustment for changes in medical treatments within 12 months of diagnosis.
The authors conclude that, "The improving trends in 12 year survival are associated with progressive use of evidence based treatments". They further surmise that these changes are "contributing to the continuing decline in mortality from coronary heart disease".
Action: Clinicians should be reassured that the implementation of interventions that are backed by a sound evidence base are likely to result in reduced mortality and morbidity.