As the UK descends into hysteria around petrol and pasties, I have been reflecting for the last week on Peter Rothwell’s recent Lancet papers about cancer prevention and the role of aspirin. Basically, daily low-dose aspirin not only prevents development of new cancer, but also the spread of cancer. Aspirin is one of the oldest drugs in the drug cabinet of hospital wards and GP surgeries, but we continue to discover more about its roles in medicine. As new evidence appears on the horizon, the information and guidelines for practising doctors and their patients still continues to change. There are inevitably time delays in how quickly new information filters through healthcare settings and broader society, and how it is interpreted by both the patient and the doctor.

Aspirin has several different uses which are proven by large bodies of evidence, including as a painkiller, prevention of cardiovascular disease in people at risk (primary prevention) and people with known cardiovascular disease (secondary prevention) and now for prevention of cancer. I always love to refer back to the Hippocratic Oath, and so we have to weigh aspirin’s harms with these many benefits. The main harm with aspirin is bleeding, particularly people who have a tendency towards bleeding anyway, e.g. individuals with history of gastric ulcers.

Interestingly, as the new data is emerging about the long-term preventive effects on cancer, the use of aspirin for two other indications is in decline due to evidence of not that much good when weighed against the risk of bleeding. First, most doctors do not recommend low-dose aspirin for primary prevention of cardiovascular disease, largely due to available data from meta-analyses showing that it does not change mortality in diabetics or non-diabetics. Second, in patients with atrial fibrillation, a heart rhythm problem which increases risk of stroke, aspirin is no longer recommended, yet most guidelinesaround the world still include it. So while we can recommend aspirin for long-term cancer prevention, we may not be able to recommend it in healthy individuals for long-term stroke prevention.

Evidence-based medicine is following a moving target of diseases and treatments and so the evidence is also always changing, even for drugs as old as aspirin. So for newer drugs, you can begin to imagine how little we know. The challenge is to keep all people, both doctors and patients up-to-date with all available evidence and guidelines. However, we know that this is difficult, given that both doctors do not always follow guidelines and people do not generally like to take tablets. Notably, most news reports covering the “aspirin and cancer” story advised people to go and see their doctor before starting the drug. Fergus Walsh, of the BBC, quoted a notable academic, “Doctors were good at treating disease, but when it came to preventing ill-health then people had to make their own judgements”. I agree. I wonder whether people have as much chance of making the “right decision” themselves. And before you ask, I do not take an aspirin a day yet, but I did start cycling to work again this week. One preventive step at a time.

Since the early trials of beta-blockers and thrombolysis, or “clot-busting” drugs, in cardiovascular disease, the American Heart Association Scientific Sessions and other international cardiology meetings have been dominated by highly-anticipated “late-breaking” or “hot trials” sessions. During these talks, thousands of conference attendees would clamour to hear the results of trials of new drugs reported for the first time. As well as being highly talked about, they greatly influence projections of how the drug will perform in the real market: akin to a stockmarket floor for pharma. Today new drug trials are still by the dozen, but difficult economic times, increased regulation of pharma and wider and quicker dissemination of results may be changing the role of these sessions.

Aside from the trials, three messages are coming through loud and clear from this year’s meeting in Orlando. First, although the best-attended sessions are still the trials of new interventions and drugs for the range of cardiovascular disease, the number of talks devoted to primary prevention and primordial prevention is growing. In other words, prevention of the development of disease and prevention of the development of risk factors of disease, respectively

Second, there is a shifting focus on risk factors as continuous exposures over the whole lifespan. For example, we have talked about “pack-years” of smoking for a long time, i.e. an individual’s lifetime exposure to cigarette smoke. Rather than looking at arbitrary cut-offs for risk factors such as hypertension or high cholesterol, it may make more sense to look at the burden of that risk factor over their lifespan, and in combination with other risk factors.

Third, in the aftermath of the September UN high-level meeting, there is an increasing recognition of the global health aspects of heart disease and stroke. In a session chaired by Professor Sir Magdi Yacoub, eminent cardiac surgeon and long-term activist for improved health services for heart disease in low-income countries, a researcher from Mozambique showed the huge disease burden how feasible screening for common heart diseases can be, even in rural settings.

All three of these changes are welcome and signal gradual, encouraging paradigm shifts among both researchers and health professionals to look at the bigger picture of prevention and population approaches to cardiovascular disease.

Working in cardiology, it is sometimes hard to keep up with the stream of high-tech gadgets, new drugs and treatment technologies which are constantly changing diagnosis and treatment of cardiovascular disease (CVD). For example, cardiovascular drugs (such as those against cholesterol and lipid disorders, and antithrombotic agents) account for the majority of blockbuster pharmaceuticals.

There is no question that CVD is common, causing more than 150 000 deaths annually in the UK alone, with annual costs in excess of £30 billion. That is why there have been massive, coordinated efforts to focus on every aspect of heart disease treatment and prevention.

However, we tend to focus on the expensive, labour-intensive, training-intensive strategies. For example, primary angioplasty is an invasive procedure to open up blockages in the blood supply to the heart immediately after a heart attack. It requires training of all staff, 24/7 cover and the necessary equipment and post-procedural care. A conservative analysis estimated the cost of a primary angioplasty in usual working hours to be £5176 with an extra £245 if undertaken out of hours. The authors of this study estimated that angioplasty added £4520 for each quality-adjusted life year (QALY) gained. Expensive stuff when you are providing this service to the whole population.

Are there cheaper, lower-hanging fruit? Of course there are, but no drug companies or vested interests are pushing them. Of the neglected risk factors with most public health impact, diet is the Cinderella at the Cardiovascular Ball. In this week’s BMJ, an economic model of CVD in the UK shows yet more evidence for Geoffrey Rose’s population strategy to disease. The authors give us three poignant take-home messages from the study. First, a 5% reduction in mean cholesterol or blood pressure in the population would save the UK at least £80-100 million. Second, legislation to reduce salt intake by 3 g/day (and we are currently having 8.5g/day on average) would prevent 30 000 cardiovascular events and save £40m a year. Third and perhaps most interestingly, legislation to reduce intake of industrial trans fatty acid by approximately 0.5% of total energy content may add 570 000 life years, saving £230million a year. NICE has been pushing for a dietary ban of trans-fats for some time.

Nobody is saying we don’t need the latest and best evidence-based tools and therapies for CVD prevention, but these numbers are hard to argue with. As I finish a night shift, I am going to forego my greasy fry-up for a bowl of muesli after reading this.