Preventing heart disease – a continuing story
BY PROFESSOR STEPHEN LEEDER, EMERITUS PROFESSOR PUBLIC HEALTH, UNIVERSITY OF SYDNEY
Public Health England (PHE) is the organisation responsible for the oversight of all preventive activity in England. This ranges from vigilance for infectious disease outbreaks and epidemics, through immunisation programs, to advice and support for prevention in general practice – including that relating to non-communicable diseases, especially circulatory disorders.
With the increased prevalence of cardiovascular disease in an ageing population, PHE has been reviewing investment in its prevention strategy. (https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/749866/CVD_ROI_tool_final_report.pdf)
As in Australia, since the mid-1960s, deaths in middle age from heart attack have decreased in England by well over 50 per cent. This is attributable, almost equally as best we can tell, to improvements due to primary prevention, most notably dramatic downturns in smoking, and to improved treatment.
Falls in the rate of ‘sudden death’, which are substantial, are an obvious place where primary prevention is working. But the evidence is difficult to collect and assess. As Earl Ford, an American epidemiologist, and Simon Capewell, a clinical epidemiologist from Liverpool University in the UK, wrote in 2011 (www.annualreviews.org/doi/full/10.1146/annurev-publhealth-031210-101211), “Changes in risk factors may explain approximately from 44 per cent to 76 per cent of declining CHD mortality and treatments may explain approximately from 23 per cent to 47 per cent. Thus, both prevention and treatments have contributed immensely to the decline in CHD mortality.”
Nevertheless, despite these advances, cardiovascular disease remains a major problem. This year, according to calculations from the Australian Heart Foundation, based on data from the Bureau of Statistics, about 8,000 Australians will die from a heart attack.
Heart attack death was previously restricted to economically advanced societies, but it now spread widely through economically developing, and even the poorest, nations. Here, death from heart disease follows the pattern we saw in Australia before the decline in mortality began in the 1960s, namely, middle-aged men and women, rather than the elderly, being at serious risk. Our effectiveness in managing infectious disease in those less affluent countries means that those people are now more prone to the degenerative diseases familiar to us.
What is the scope for prevention in clinical practice? A survey this year by the Heart Foundation found: “One in two Australians who have had a heart attack [and there are about 40,000 of them under 55] continue to smoke. Of these, close to 40 per cent did not even attempt to quit … almost one in four have failed to regularly monitor their blood pressure levels. More than a quarter are not having regular cholesterol checks. Around one in three tried to increase their physical activity levels or lose weight, however failed to maintain the changes.”
In clinical practice, prevention of death – and disability – from cardiovascular disease is a deep concern –a frequent reason for consultation and prescription and a major consumer of time in general practice.
Despite the lack of information about outcomes, Public Health England, with help from the University of Sheffield, examined the available evidence for what works and how much it costs (including general practitioners’ time). PHE settled on five interventions – detection and treatment which had merit both in terms of medical outcome and cost for:
- Atrial fibrillation (anticoagulation)
- Non-diabetic hyperglycaemia (‘pre-diabetes’)
- Chronic kidney disease.
Based on a 2014 health survey in England, the prevalence of individuals aged 16+ with one or more of these high risk conditions was 49 per cent.
The best evidence concerning effective interventions for each condition was then assembled, along with data on the cost of the most effective interventions and the duration of likely effect following the interventions. This information was combined into a package which allows individual practitioners to calculate the local costs and benefits of these interventions in their practice.
“The single intervention with the highest net total savings in the short term (years 2-5) is to optimise the proportion of people taking statins… a saving of £700 million in England [total population: 45 million] by year five. However, in the long term (20 years), optimising antihypertensive treatment is the single intervention predicted to save the most money (over £2 billion)… but most of the lifestyle interventions are not cost-saving over 20 years.”
What may we conclude for Australia? Among the preventive interventions for managing cardiovascular disease in general, and heart disease in particular, we are committed to long-term care for optimal effect. This may not become obvious for 20 years, but this is not to gainsay it.
Preventive treatment requires a philosophy of long-term care and support to be effective.
Published: 06 Dec 2018