Misinterpreting mortality

On the same day that the story about a levelling of life expectancy (LE) and possible links to austerity hit the press, the Journal of the Royal Society of Medicine published my letter responding to the paper that sparked a flurry of interest in the same topic earlier this year. That paper was entitled “Why has mortality in England and Wales been increasing? An iterative demographic analysis“.

Irritatingly, I have no budget to pay for open-access publication, so although the original paper is freely available, my letter outlining the paper’s errors is not. In addition, as the JRSM does not publish letters as “advance access”, the points I wished to make have been held back for 3 months. This feels pretty unsatisfactory.

One side of the argument is out there and its refutation is not, which is a shame as the paper has some profound flaws – none of which have stopped the authors from quoting the paper as if it were reliable:

McKee copy

In addition to which, the authors’ response to my letter suggests the critique to make little difference to their conclusions. I am not persuaded.

So here is a summary of what is wrong with its analysis.

  1. The paper claims to be an analysis of age-standardised mortality and makes some play of the need for standardisation. But the data it quotes and illustrates are not standardised. Instead, they are crude mortality data both in the text and in figure 1 of the paper. The proportional changes described at the top of the right hand column of text on the 2nd page are of the crude mortality rates. It is not true, as the paper states, that age-standardised rates are higher than at any point since 2008, as they were higher in 2010 – an error also stated in the abstract. Subsequent analysis is manifestly predicated upon this error.
  2. The methods section does not accurately describe the source or handling of the data. The citations imply the use of standard release data, whereas having run into a brick wall on these, it turns out that the authors used a specific run of data obtained from ONS. How they handled data above the age of 90 is unclear.
  3. The methods section also omits to mention that the comparison of years used mid-year to mid-year data rather than calendar year. This renders the findings of the paper non-replicable if the described method is followed. The labelling of those data in figure 2 is also incorrect as a consequence – they should indicate 2013-14 and 2014-15. Moreover, this very markedly amplifies the winter excess effect of 2014-15. Excess winter deaths data for 2015-16 are now available and show a fall of the excess rate back to the average of recent yearsPicture1It is worth noting here also that the excess of winter deaths in 2014-15 is not unprecedented, but also occurred as similar levels in the 1990s.
  4. Taken together, the errors of non-standardised rates and exaggeration of the winter 2014-15 effect in the overall figures renders dubious the claim of a clear change in trajectory of mortality. When the genuinely age-standardised fall to 2014 is considered it looks like this:Trend 1
    It is only when the 2015 data (which include most of the bad winter effect) are added into the trend that it looks to have stalled:Trend 2
    Visually, the up-tick of the graph changes the way we perceive the data quite markedly.
  5. In the last paragraph of page 2 of the paper it is stated that the supposed trend in deaths “cannot be explained by population ageing”. This is a conclusion that could only genuinely be drawn from analysis of the age-standardised figures. But having drawn that conclusion from what are actually crude data, the authors then present the crude excess of deaths by month in figure 3 against a baseline of average deaths in 2006-2014. No explanation is offered for the curious choice of a 9-year baseline. The annual excess of deaths over the crude average for that period of 9 years is 30,515. However, these should be compared with standardised figures. In fact, the excess age-standardised rate in 2015 when compared with 2006-2014 is -32 per 100,000, which would be equivalent to -18,331 deaths if applied to the mid-year population estimate for that year. Either way, this is an essentially arbitrary analysis since there is no logic to use of a 9-year baseline as the comparator. I note also that the paper states in relation to the excess figure of 30,515 that “calculations of excess deaths in this paper vary slightly due to differences in standardisation in various comparisons”. I think the juxtaposition of that number and statement is misleading, since it implies the figure to be standardised when it is not.

Altogether, the errors in the paper are extensive and fundamental to its entire thesis. They seem to me to kill the assertion that there is yet evidence of a real change in mortality trend. What remains is simply the very substantial excess winter deaths figure for 2014-15. The key point is surely to ask whether there is an underlying trend once the noise of winter variation is removed. I do not believe that has been demonstrated in this paper.

Life expectancy…

Has it stopped rising? From what I can gather even Michael Marmot only really said that a) its rate of increase had slowed and b) that it was worth investigating whether austerity might be involved. None of which stopped the story being way more extreme on both counts, fuelled in some cases by people who really ought to know better.

So what to think? The first thing to remember is that Life Expectancy (LE) is a fairly artificial construct. It doesn’t actually describe the likely lifespan of anyone, given that it is constructed from contemporary risks – as if a baby born today were to experience today’s age specific risks throughout life. As a result, LE as a measure can change rapidly because of contemporary pressures.

Secondly, the excess winter deaths of 2014-15 make a substantial difference to the calculations and visual appearance of the data. We will only really know what is happening with that trend when we can see if that was a one-off event or something more sinister.

Thirdly, the appearance of slowed increase in LE may be more the result of an upward deviation from trend between 2009 and 2011 rather than a subsequent downward deviation, thus:

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Without those better, earlier figures the furthest right points would not appear anomalous, notwithstanding the 2014-15 excess winter deaths.

This sort of pattern also invites speculation that there is a ‘frail survivor’ effect here, whereby older individuals, having avoided earlier insults, are particularly vulnerable when subsequently exposed to e.g. a new circulating viral strain.

On Radio 4 this morning, the ‘Thought for the Day’ speaker reflected the suggestion that we could be reaching a limit to extension of life expectancy. To which it is worth pointing out that people have been predicting that for many years and have found it necessary repeatedly to revise their assumptions (e.g. see Oeppen J, Vaupel JW. Broken Limits to Life Expectancy. Science (80- ). 2002;296(5570):1029–1031.)

 

The view from the Acropolis…

Outdoor pollution, worldwide, is estimated to kill 3.7 million people per year. This is not a typo. Combine these with deaths from indoor pollution and the total passes 7 million, or about 1 in 8 of all deaths according to Dr Maria Neira, Director of the WHO Public Health and Environment Department.

As I (EM) write this from an (austerity budget) hotel in Athens, those statistics on pollution-related deaths seem of a piece with the unending torrent of traffic. If the volume were not sufficient to generate a surfeit of particulates, the local style of driving—full speed between the traffic lights then slam on the brakes—surely exacerbates it. This may be of little consequence for me—as a jaywalking Englishman I am unlikely to survive the ‘red lights don’t count if you are turning right rule’ long enough for air quality to matter. But figures published by Public Health England earlier this year suggest around 25 000 English deaths per year are attributable to long-term exposure to particulates.1

So, why Athens?

Because the European and Global Healthy Cities Movement celebrates its 25th anniversary this year, and is meeting to mark the occasion with a conference on ‘Health and the City: Urban living in the twenty first century’. The movement now numbers 99 European cities within its networks, and is moving into its sixth phase with a feeling that city-level action and influence are set to grow yet stronger.

Pollution, traffic, and infrastructure provided the basis for many of the great public health interventions of the past, and there is every reason to believe that they will continue to be defining issues for the health of generations to come. By 2030, more than 70% of the world’s population will live in cities. City health will dominate the fate of the larger part of world population.

The meeting feels revitalized by the growing stature of city leaders and initiatives. Former New York mayor Michael Bloomberg looms large. ‘City health diplomacy’ is a phrase that recurs. Inequalities will not be solved by individual interventions. But they can, and have in the past, been narrowed by the kinds of population-based approaches that are the realm of local government.

In this issue, Gorsky et al. look at lessons from public health in England as it was practiced in the past, growing from the city-based health initiatives of the Victorians.2 Since public health ‘came home’ to Local Authorities in England in April 2013, it is pertinent to consider how its practice will differ not only from almost 40 (wilderness?) years in the NHS, but also how it might echo or depart from the great strides made in the time of Medical Officers of Health. Can modern Directors of Public Health and their colleagues live up to their forebears? Day, Shickle and colleagues propose five talents for public health leadership, and consider the challenges of engaging high-profile champions.3,4These are contributions to a debate that will continue to echo across the globe, since one of the great messages of the Healthy Cities experience is that the local is universal. If a problem exists in Preston, it is likely, in some form, also to exist in Lodz.

Following the news and Twitter feeds from back home during the meeting, the publication of the ‘Five Year Forward View’ leapt to the fore.5 The English National Health Service is currently funded at a level billions of pounds short of that envisaged in 2002 by Wanless in even his most optimistic (‘fully-engaged’) scenario, and Simon Stevens has now staked his claim on future governments to make good at least £8 billion of that shortfall.6,7 Even more significant, we would argue, is the emphasis placed on greater local powers to improve health, with a system-wide shift towards prevention.

While national politicians of all colours examine their fingernails intently and try to ignore the conclusion, obvious to the rest of us, that at some point we need to start talking about raising tax to pay for necessary services, local approaches can go at least some of the way towards amelioration of needs that will grow with demography.

Some aspects of public health are far from new, but others, such as social media, have no real precedent. Amelia Burke-Garcia and Gabriel Scally explore this new world in ‘Trending now: future directions in digital media for the public health sector’, with accompanying commentaries.8–10 We have placed this debate under ‘Wider Determinants’ because the rise of social media is a phenomenon that defies classification as an intervention. We may try to influence its direction but it has an immense and amorphous independence. Gabriel is in Athens, speaking on this and other issues from his long engagement with Healthy Cities. He describes its potential power, for a whole new type of public health engagement, but warns of its double-edged nature, as some of us have already found to our cost.

Finally, we are grateful to Jose Martin Moreno for his reflections on the still unfolding tragedy of Ebola—an avoidable disaster that demands reflection on our collective culpability, and on how, in the words of Denmark’s Crossing Borders ‘a virus turned into a racism outbreak’.11

1          Public Health England Estimating local mortality burdens associated with particulate air pollution, 2014 Chilton Public Health England

2          Gorsky M, Lock K, Hogarth S. Public health and English local government: historical perspectives on the impact of ‘returning home., J Public Health, 2014, vol. 36 (pg. 546-51)

3          Shickle D, et al. Mind the public health leadership gap: the opportunities and challenges of engaging high-profile individuals in the public health agenda, J Public Health, 2014, vol. 36 (pg. 562-7)

4          Day M, et al. Training public health superheroes: five talents for public health leadership, J Public Health, 2014, vol. 36 (pg. 552-61)

5          NHS England Five Year Forward View, 2014

6          Wanless D., Securing our future health: taking a long-term view, 2002 London HM Treasury

7          Wanless D., Securing good health for the whole population , 2004 London HM Treasury

8          Burke-Garcia A, Scally G. Trending now: future directions in digital media for the public health sector, J Public Health, 2014, vol. 36 (pg. 527-34)

9          Aspinall PJ. Commentary on ‘Trending now., J Public Health, 2014, vol. 36 (pg. 535-6)

10        Oyebode O. Commentary on trending now: future directions in digital media for the public health sector, J. Public Health, 2014, vol. 36 (pg. 537-8)

11        Santos C. Crossing Borders, 2014 http://crossingborders.dk/the-politics-of-ebola-how-a-virus-turned-into-a-racism-outbreak/

https://doi.org/10.1093/pubmed/fdu093 Published: 26 November 2014
© The Author 2014. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Lots of planets have a North . . .

Stuart Maconie’s splendid examination of England’s North, Pies and Prejudice, is prefaced with an exchange between Rose Tyler and the Doctor from an early episode of Russell T. Davies’s regenerated Dr Who: ‘If you’re an alien, how come you sound like you come from the North’ asks Rose. ‘Lots of planets have a North’ replies the Doctor, in a definitive Mancunian tone.1

Indeed they do, though sometimes the North is the East, or a specific locale, or the poor.

Owen Jones, author of Chavs – The Demonization of the Working Class, recently dismissed the English North–South divide as a myth.2 There is one division that matters, he argued, ‘those who have wealth and power, and those who do not’. If wealth and power are concentrated in the South, the point would seem rather to be that territorial divisions reflect and reinforce socioeconomic ones.

Responding in the New Statesman, James Maxwell pointed to the disproportionate impact on the North of public sector cuts, and to the long-standing disparity in infrastructure investment within the UK.3 London and its surrounding areas, according to IPPR North, receives over 80% of all planned transport spending, and an estimated 15 times greater share of arts and culture funding than other English regions.

Here, the comparison drawn by Bambra et al., in our guest editorial, of England’s North–South divide with that between East and West Germany before and after unification is pertinent.4 The principal causes of the German convergence of mortality have been identified by Vogt and Gampe as availability of health care and increasing pension levels.5 Since the North of England already enjoys health care that appears to be the match of, or superior to that elsewhere in country, this suggests that economic inequality remains the UK’s biggest problem in achieving geographical equality of health, wellbeing and life expectancy.6

This is no surprise to students and practitioners of public health, and has been a central message of reports from Black to Marmot.7 Yet public health debate is still too often focussed on individual behaviour and choice, and public health practice on efforts to influence those, notwithstanding the widespread recognition that those behaviours and choices are powerfully shaped by external factors. Many of these are beyond the influence of public health practitioners or the institutions that have primary responsibility for public health.

In this context, we have taken the opportunity as editors of our first Journal of Public Health issue to revise the categories in which articles are presented. While we recognize the importance of health improvement, health protection and health care services in the study and practice of public health, we also feel the need to reflect the relative importance of approaches at societal and personal levels. To this end, we have restructured the core content according to: In this edition, only four of these categories appear—Behavioural Factors is absent—although we plan to focus on alcohol in the next issue, with articles that will fall under this heading as well as under others. We invite submissions that consider public health with these categories in mind. Other sections, e.g. Chekhov’s Corner, Perspectives, Training & Education, will continue to appear on an ad hoc basis.

  • Wider Determinants of Health (politics, economics, environment)
  • Life Course and Epidemiology (self-explanatory)
  • Behavioural Factors (e.g. tobacco use, alcohol)
  • Interventions (prevention and services)
  • Methods (self-explanatory)

Finally, a small correction to our esteemed predecessors; in his valedictory editorial, Gabriel Leung described us as both as being ‘of Newcastle’.8 In fact, we are both of Durham University while one of us (E.M.) is also Director of Public Health for Newcastle. Either way, we are delighted at the opportunity to steer the journal, and add to it what we hope will be a usefully Northern perspective as well as a global (or even planetary) one.

 

1          Maconie S., Pies and Prejudice: In Search of the North, 2007 London Ebury Press

2          Jones O. The north-south divide is a myth – and a distraction, Guardian 4 May 2014

3          Maxwell J. Of course there is a north-south divide – and of course it matters, New Statesman 7 May 2014

4          Bambra C, Barr B, Milne E. North and South: addressing the English health divide, J Public Health, 2014, vol. 36 (pg. 183-6)

5          Vogt T, Gampe J. Money or Medicine? The contribution of rising income and improving health care to the East-West German mortality convergence, 2013 Population Association of America: 2014 Annual Meeting (pg. 1-7) Boston

6          Bevan G, Karanikolos M, Exley J, et al., The Four Health Systems of the United Kingdom: How Do They Compare? 2014 London The Health Foundation

7          Marmot M., Fair Society, Healthy Lives: tThe Marmot Review, 2010LondonThe Marmot Review

8          Leung GM. Mission accomplished: over and out, J Public Health, 2014, vol. 36 pg. 1

Journal of Public Health, Volume 36, Issue 2, 1 June 2014, Pages 181–182, https://doi.org/10.1093/pubmed/fdu036 Published: 01 June 2014

 

© The Author 2014. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.