Skip navigation
Link to Back issues listing | Back Issue Listing with content Index | Subject Index

Prevention or cure?

Healthy living evidence
Technology or tomatoes?
Changing the future
Comment

'Politics is the art of preventing people from taking part in affairs which properly concern them' (Paul Valéry, 1946).

In the UK over the last year or so, public and professionals have been bombarded by messages about obesity, lack of exercise, healthy eating, exercise, salt, smoking, safe sex and teenage pregnancy, to name but a few. Media and individuals have taken to criticising the 'nanny state' that tries to tell us what to do with our lives.

Bandolier is no defender of states or governments, nanny or otherwise, but for some time the evidence has been accumulating that healthy lifestyle trumps anything that medicine can offer, and infinitely more than the multitudes of quackeries written about in our newspapers. Media seems to be oblivious to the irony of attacks on health promotion (for which there is a wealth of good evidence of massive effectiveness) while they promote voodoo nonsense (for which there is good evidence of ineffectiveness or no evidence of any effect).

Time, then, for some quiet reflection, and a further look at the evidence about which does best, healthy living or treating the unhealthy. But first a declaration of initial bias: Bandolier is a firm believer that the best way to see your doctor is socially. Another bias is the belief that giving people good information on how to avoid illness could be much better done, and it properly concerns every one of us, as individuals and taxpayers.

Healthy living evidence

There is a lot, and much has appeared in these pages over the years. A good example (Bandolier 78) was from the US Nurses study, that showed that those with a good diet, who did not smoke, and who had enough exercise had less than half the risk of heart disease compared with those who had none of these markers of good health. For those who additionally had a normal BMI and who drank alcohol moderately, the risk was down to a quarter. The trouble was that only 1 in 8 women were in the former category, and only 1 in 30 in the latter.

The Bandolier Internet site has collected all this together in one easily navigable area. Whether it is heart disease, or cancer, or bone density, arthritis, macular degeneration, or whatever, the message is the same. If you:

then the chance of having something nasty happen to you is very, very, much reduced.

Of course other factors, like poverty, or unemployment, or living conditions also come into play, and can affect health significantly. Wales (population about 2.5 million) has many of these issues, and the economics of health in Wales have been examined with a very broad brush [1]. Noteworthy was that in 2001, 81% of expenditure was on illness (£2.4 billion, or about £1,000 per person), while the spending on health promotion was one thousand times less, at £2.3 million (or £1 per person). Each person in Wales had 13 prescriptions over a year (it is 10 in England).

Technology or tomatoes?

Over the last few decades there have been large reductions in deaths from coronary heart disease in industrialised countries. Two main reasons for this present themselves (Figure 1):



Figure 1: Competing influences reducing CHD deaths





A number of studies have sought to evaluate which has done most (Table 1). In the USA, UK, and New Zealand a rough answer is that about 40% of the reduction comes from better treatments, and about 50-60% from reduction in risk factors.



Table 1: Selection of studies on medical and risk factor effects on CHD deaths



Reference Study Methods Main results
Hunink et al. JAMA 1997 277: 535-542 Examine secular trends in risk factor levels and improvements in treatments on decreased CHD mortality in USA 1980-1990 Use of literature reviews, US statistics, surveys, ongoing clinical trials.
Computer simulation models
Annual coronary mortality 34% (127,000 deaths in 1990) lower than predicted from steady state.
25% of decline by reduction in risk factors in patients without CHD
29% of decline by reduction in risk factors in patients with CHD
43% by other improvements in treatment and patients
Capewell et al. Heart 1999 81: 380-386 Estimate fall in Scottish CHD mortality due to risk factor changes or medical treatment changes 1975-1994 Systematic reviews and meta-analyses of RCTs, Scottish epidemiological studies Annual coronary mortality 29% (6205 deaths in 1994) lower than predicted from steady state
51% due to risk factor changes
40% due to treatments
9% other
Capewell et al. Circulation 2000 102: 1511-1516 Estimate fall in Auckland (NZ) CHD mortality due to risk factor changes or medical treatment changes 1982-1993 Systematic reviews and meta-analyses of RCTs, Auckland epidemiological studies Annual coronary mortality 24% (558 deaths in 1993) lower than predicted from steady state
54% due to risk factor changes
46% due to treatments
Goldman et al. J Am Coll Cardiol 2001 38: 1012-1017 Estimate impact and cost-effectiveness of risk factor reductions 1991-1990 (extrapolated to 2015) Use of large validated databases and computer modeling Change in risk factors resulted in about 430,000 fewer CHD deaths and 740,000 total deaths over the period, estimated cost per life saved of $44,000
Extrapolated to 2015 was saving of 3.6 million CHD deaths and 1.2 million non-CHD deaths at cost of $5,400 per life saved
Unal et al. Circulation 2004 109: 1101-1107 Estimate fall in English & Welsh CHD mortality due to risk factor changes or medical treatment changes 1981-2000 Systematic reviews and meta-analyses of RCTs, epidemiological studies, official statistics Annual coronary mortality 62% lower in men, 45% lower in women (68,230 deaths in 2000) than predicted from steady state
58% due to risk factor changes
42% due to treatments


The numbers of deaths averted are not trivial, amounting to 68,000 a year in England and Wales in 2000 over what would have been expected from 1981, for instance. Moreover, efforts to improve coronary health appear to be cost-effective, with a US estimate extrapolating efforts in the 1990s to benefits up to 2015 producing a cost of $5,400 for each life saved.

Large and long epidemiological studies [2] can attribute only a proportion of the benefits from reduction in CHD deaths to classical risk factors. Other, unidentified, changes must be having an influence.

Bandolier, perhaps naively, likes to think of this as the supermarket or tomato effect. We eat better than we did in the 60s and 70s, with fresh fruit and vegetables readily available all year round. Many have taken up exercise: there is an epidemic of people striding around to get their daily twenty-minutes. But beneficial behaviour is not evenly spread, and the supermarket and fast-food effect has the adverse effect of over-eating and obesity.

Changing the future

Most people with CHD have conventional risk factors. An analysis of 122,000 patients enrolled in 14 RCTs of CHD (myocardial infarction, unstable angina, and percutaneous coronary intervention) conducted in the 1990s showed that 85% of women and 81% of men had at least one conventional risk factor [3].

If levels of risk factors keep falling, what does the future hold?

The answer for the UK seems to be continued large reductions in CHD death rates [4]. Using Scottish data extrapolated to the UK, and extrapolating a continuation of current trends to 2010 for those under 75, it calculates 24,000 fewer deaths in 2010 from reductions in smoking prevalence, and blood pressure and cholesterol. That is close to the present UK government target of 28,000 fewer deaths in 2010.

Bigger changes in population risk factors through lifestyle changes could produce bigger benefits. For instance, getting smoking prevalence down to 18%, getting average cholesterol levels down to 5.2 mmol/L, and additional lowering of blood pressure by 3-4 mmHg, could double the number of deaths prevented or postponed. Improved medical treatments and the tomato effect could add to this.

Comment

All of which makes one wonder about that miserly £1 per person spent on health promotion. The evidence from the US nurses study is that most people, well over half, do not have a fully healthy lifestyle, despite the fact that nurses can be expected to be educated and informed. We also know that most people with CHD have risk factors.

There is a clearly a job to be done to better inform people about how they can have a better and longer life. The solution, or at least a large part of it, lies in their own hands, but they have to believe in the message. Is nanny state-ism the best way? Who knows? The state does have enormous powers to improve the underlying culture. Anyone visiting New York, or Ireland, where public place smoking bans are in force can testify to impressive change for the better, with a large degree of public consent.

We spend masses on getting evidence about treatment effectiveness, but not much on how to get a healthy-living message across. Bandolier, at any rate, has looked and been disappointed. Our experience is that people respond best when given evidence rather than exhortation.

A famous advertising equation says:

Satisfaction = performance - expectation

It does just what it says on the tin. Which is why governments set modest targets, and then achieve them. All of which sort of prevents us from taking part in affairs that properly concern us. We should press for more and better.

There are legitimate concerns about individual liberty and the rights and concerns of society. These extend to what the public health message is, and who delivers it. What is astonishing is that it is being delivered most publicly by those we are least inclined to believe.

But the bottom line is this: the reduction in conventional risk factors for CHD will also help a whole range of other conditions, and leave us healthier for longer in several ways.

References:

  1. C Phillips, R Tudor Edwards. Economics of health in Wales. Welsh Economic Review 2002 14: 26-30.
  2. K Kuulasmaa et al. Estimation of contribution of changes in classic risk factors to trends in coronary-event rates across the WHO MONICA project populations. Lancet 2000 355: 675-687.
  3. UN Khot et al. Prevalence of conventional risk factors in patients with coronary heart disease. JAMA 2003 290: 898-904.
  4. JA Critchley, S Capewell. Substantial potential for reductions in coronary heart disease mortality in the UK through changes in risk factor levels. Journal of Epidemiology and Community Health 2003 57: 243-247.

previous or next story