Unequal Health In New Zealand: Always Like This?

Alistair Woodward & Tony Blakely

There are large inequalities in health in New Zealand. This much is well-known, as is the fact that health care interventions and public health efforts often fail to make things better, and indeed may entrench disadvantage. Was it always like this? In fact, no. We are not suggesting there was a golden age when health was distributed absolutely equally. But there is plenty of evidence that the size of inequalities has varied over time, by a great deal. Here surely are clues to interventions. There must be a better chance of closing the gaps that matter most, those that are avoidable and unfair, if the history is better understood.

Let’s begin with ethnic inequalities. Early European writers and artists emphasized the robustness, vigour and apparent good health of Māori. Such accounts should be taken with a grain of salt for many reasons, but in fact when Tasman first sailed by in 1642 the mortality rates of the indigenous people may have differed little from the Dutch. At this point all Europe suffered from plagues, famines and civil strife, mortality was particularly severe in childhood, and life expectancies had not improved materially from hunter-gatherer times.

By the time that Cook arrived in Aotearoa, the demographic transition was underway in Europe and England was one of the first countries to move to a more stable and relatively benign mortality regime. Comparisons based on estimates of age at death from skeletal remains suggest a difference of perhaps 10 years in life expectancy at birth between late 18th century England and Māori. Such calculations are necessarily tentative, but there is little doubt the gap widened greatly in the following hundred years.

The swamping of Māori by immigration from Europe, and the transfer of natural resources, land especially, to new arrivals brought in Mason Durie’s words “decline, disease and dispossession”. There were no systematic statistics on deaths or population numbers (registrations of Māori births and deaths were not compulsory until 1913), but case reports, occasional surveys and subsequent modeling (for instance, based on the ratio of women to children) indicate that life expectancy at birth at the end of the 1800s may have been as low as 20 years. This was thirty years less than the expectation for non-Māori.

The Māori renaissance of the 20th century was evident in population growth, economic recovery and improvements in health, both in absolute terms and relative to non-Māori. As the quality of the data improves during this time, we can be increasingly confident about the diminishing inequality in life expectancy. By the 1980s the gap between Māori and non-Māori had reduced from thirty to between 5 and 10 years. The economic upheaval of the late 1980s and early 1990s was a significant setback. Also non-Māori life expectancy surged ahead in the 1980s after the worst of the Ischemic Heart Disease epidemic – which may have lingered longer for Māori. As a result inequalities in health widened during the 1980s to 1990s, but it proved only a temporary interruption. Recently life expectancy for Māori has improved year on year faster than non-Māori, though not by much – at the current rate it will take many more decades to achieve equality.

Elsewhere we have written at greater length about why and how the history of New Zealand has shaped the health of its people. The essential point is the present 7 year gap in life expectancy at birth did not drop out of the sky – there is a long back story, a story of contact, colonisation and recovery.

A similar waxing and waning is apparent in geographic inequalities. From the time that reliable statistics were first available until about 1940, that’s a period of 70 years, non-Māori New Zealanders lived longer than anyone else world-wide. After 1940 New Zealand, and Australia too, fell off the pace, and by the mid-70s were about 5 years behind world-best life expectancy. Then the long-run upwards trend resumed, at a rate in excess of most other countries, so that for males in particular New Zealand is now gaining rapidly on leading countries such as Sweden and Iceland. International comparisons, including the see-sawing contrasts between New Zealand and Australia, help to distinguish two important categories of causes of population health: those factors that explain the direction we are taking, the extraordinary long-term decline in mortality for instance (which remains largely unexplained); and the causes of short-term perturbations (such as economic recessions and epidemics).

Whatever measure is applied, the health of males and females tends to differ, most frequently to the disadvantage of males. Is this an inequality that is “avoidable and unfair”? The large fluctuations over time in excess male mortality suggest that at least some of the inequalities between males and females are avoidable. Two hundred years ago death rates were similar among males and females, and indeed at some ages, women’s rates were higher than those of men, due principally to high maternal mortality. In the twentieth century there was a remarkable divergence, most evident in middle age, with male mortality rates up to three times those of females – in New Zealand the sex difference in life expectancies peaked around 1970, at about 6 years. To a large extent the cardiovascular epidemic was behind this, and a confluence of biological vulnerability and socially patterned risk factors (cigarettes in particular) affected men particularly severely. With the downturn in heart disease, the difference in life expectancies is shrinking fast, and presently sits at about 4 years for Māori, and 3.6 years for non-Māori. In many respects, it is true, male female inequalities in health are hard-wired, but innate differences may be smaller than is often assumed. Clearly there is a significant overlay of social, cultural and environmental factors that amplify biological differences and, one might postulate, are amenable to change.

Health inequalities by age are the largest of them all, but again, we argue that it would be a mistake to assume that these are pre-determined or fixed, and there may be more room for improvement than was thought previously. Life expectancy is rising, as already noted, and this is now due largely to declining mortality at older ages. The age at which remaining life expectancy first falls below 15 years has risen (for women) from about 58 years in 1900 to 75 years in 2012, and is projected to climb to 80-85 years mid-century. These projections are uncertain of course, but there is no sign that humans have reached a hard limit on life expectancy – the longest lived group in the world, Japanese women, continue to do better every year.

Quality is at least as important as quantity, you might reasonably say, and are these extra years worthwhile additions to the life span? It is difficult to determine with confidence trends in healthy life expectancy because “healthy” is a slippery concept, and the perception, definition and reporting of poor health may all vary over time. A recent report from Statistics New Zealand found only minor changes in independent life expectancy from 1996 to 2013, and an expansion of years lived with self-reported disability requiring assistance. Other work, using different measures, paints a different picture. In Germany, for instance, psychological testing of successive birth cohorts has found that population ageing is decelerating in terms of cognitive function: a sign perhaps that the Flynn effect (the remarkable improvement in IQ scores over the last hundred years) applies at all ages.

The weight of the evidence, in our view, points to a generally positive conclusion – at any given chronological age there are more people, generally in better shape, than in the past, and this is both a challenge (because disability accumulates with age, even if at a slower rate than before), and an opportunity, since the new aged have much to contribute.

Health inequalities in New Zealand are dynamic, historical and in flux. There may be social and biological boundaries that are difficult to shift, but volatility is generally a positive feature, in our view. There are indeed plenty of options, if we acknowledge the origins and nature of the gaps we wish to close, to do better in the future.

Categories: Health, History, Inequality
Alistair Woodward & Tony Blakely
About the author

Alistair Woodward & Tony Blakely

Professors - University of Auckland & University of Otago
Alistair Woodward is a Professor of Epidemiology and Biostatistics at the University of Auckland. His professional background is public health medicine, epidemiology and environmental health. He has worked in universities in New Zealand, Australia, the UK and the United States. Present research interests include active transport - particularly the question of how to build cities to promote cycling and walking, climate change and the limits to adaptation, and environmental health risks in China. He led the work for the health chapter in the most recent IPCC assessment. With Tony Blakely he wrote “The Healthy Country? A History of Life and Death in New Zealand”, exploring the remarkable more than doubling in human life expectancy in the last two centuries. Professor Tony Blakely is an epidemiologist at the University of Otago, Wellington, He currently directs the HRC-funded Burden of Disease Epidemiology, Equity and Cost Effectiveness Programme (BODE3), which includes the modelling of the health impact of public health and cancer control interventions on health, health inequalities and health system costs. Tony initiated and implemented the New Zealand Census-Mortality Study (NZCMS) in the late 1990s, a pioneering study linking the national censuses with mortality data to allow monitoring and research on ethnic and socio-economic inequalities and the contribution of smoking to mortality. He has also led the parallel study, CancerTrends, that links census and cancer registration data to allow cancer incidence and survival studies. Tony also has research interests in mortality and longevity, tobacco, and diet. Cutting across all Tony’s research is a strong focus and interest in epidemiological and quantitative research methodologies. He co-authored “The Healthy Country? A History of Life and Death in New Zealand” with Alistair Woodward.