Do we need to live long or to live well, asks S.Ananthanarayanan.

The question of whether life has become more onerous in modern times is often raised. Has our capacity to perform declined since the time of our grandparents? What has been the price of the general increase of life expectancy that we have now?

Andrew J. Scott, Martin Ellison and David A. Sinclair, from the departments of economics at London Business School and the University of Oxford, and the Harvard Medical School, in a paper in the journal, Nature Aging, step away from subjective assessments to answer the question. Instead, they develop measures of the economic value of being alive, and examine which public health strategy may be the best investment for society to make. The approach cuts through impressions of current crises, environment, personal stress, and simply estimates the total of the value that every individual places on life itself.

The question, in fact, of choosing a short and healthy life, over a longer one with health issues, has been examined many times in the past. The paper, in the course of presenting its results, draws on paradigms in literature and cinema, and uses them to represent alternative approaches to aging and mortality.

The first of these were the people of Luggnagg, called the Struldbrugg, in Jonathan Swift’s satire, Gulliver’s Travels. The Struldbrugg grew old like the rest of us, but they could never die. As they would grow frailer with time, they were treated as legally dead when they were 80 years old, and were not allowed to own property or participate in civic life. The second is Oscar Wilde’s character, Dorian Gray, who was mortal, but did not age. In the novel, Dorian Gray had a portrait painted of himself as a young man, and it was the portrait that would age, and die, while the subject of the painting stayed young, till he died. The third case is Peter Pan, in J M Barrie’s story of a boy who never grew old, and lived in Neverland, where time did not pass. And the fourth case is of Wolverine, the Marvel Comics superhero, who could regain youth by regenerating his organs

The context is the dramatic increase in the life expectancy (LE), thanks to better nutrition and medical services, over the last 150 years. The paper, however, cites The Global Burden of Diseases, Injuries, and Risk Factors Study, 2019, which covered 204 countries, and finds that despite the increase in LE, the proportion of the lifetime spent in good health has not increased. While the years of poor health have increased, the paper notes, it is chronic non-communicable diseases – which were the cause of 73.2% of the deaths in the US in 2016, that these years are affected by. Hence the emerging body of research that emphasises the idea of “healthy aging”, the paper says.

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What should be the way forward? Should the time of illness be compressed towards the end of life? How would it help to target aging itself, which could make life both healthier and longer? Or should the emphasis be on treating specific diseases? To find answers, the paper uses a technique, the value of statistical life methodology, which puts monetary value to the gains from longer life, better health and changes in the rate at which we age.

The methodology consists of estimating what a person may be “willing to pay (WTP)” for a year’s increase in LE, at any stage of life. The WTP is related to the individuals’ lifetime expected utility. Increase of the lifetime implies more time to enjoy goods, or the levels of consumption, and leisure that are available. And improvement in the quality of life would increase the utility of given amounts of goods and leisure.

The computation used are of the American population and levels of consumption and manner of living, which would certainly not hold for other parts of the world. The paper itself states that even for the American case, the assumptions of values can be questioned and modified. The objective, however, is not monetary evaluation, but a comparison of the value of different forms of health service interventions. In respect of the relative costs and benefits of alternatives, the differences in the values of inputs considered would affect each choice in the same way. The conclusions would hence continue to be valid.

The first case considered is of just extending life while health keeps failing as before. This is like the case of Struldbruggs, where the ratio of the ‘healthy LE’ to the LE rapidly falls, a case of increasing population of the very old, all on life support. The next case is where morbidity, or serious illness is compressed to the last years, with LE unchanged. Here, the ratio of ‘healthy LE’ to LE increases, and this would correspond to Dorian Gray. In the graph shown, this case is the blue line.

The next case is where aging itself is slowed down, with improvement in health as well as mortality. As aging can be considered a result of accumulating biological damage, deterioration of both health and mortality would be slowed down. The extreme is where aging totally stops, as in the case of Peter Pan. But even in a less extreme situation, unlike Struldbruggs or Dorian Gray, there is two-fold gain of utility, in health as well as in LE.

Calculations of the WTP, or the lifetime utility, over the lifetime, show that the value increases with age. This makes sense, as older persons have larger investments to enjoy and the value of a one-year increase in the LE would be more valuable to an older person. And in the case where aging has been slowed, the higher the LE, the greater that value of increase in health, and the better the health, the higher the value of increase in LE.

In the fourth case,Wolverine, it is considered that aging is as usual till some age, say 65, where there is a restoration of youth. Here, the WTP stays lower than Peter Pan till the restoration event. There is some progress in the regeneration of tissue, its effect on longevity is not clear, and it would increase WTP, but is still not a course of intervention to consider.

The next question examined is how does the WTP for slowing down aging compare with that of reduction of specific diseases. Here the paper looks at the benefits from a drug, metformin, prescribed for type 2 diabetes, and is said to protect against “several age-related diseases.”. Insofar as such protection (as also ‘education,’ which has wide, general health benefit) amounts to retarding aging, the study shows substantial benefits, “often matching or exceeding those from the complete eradication of cancer, dementia or cardiovascular diseases,” the paper says.

“Delaying aging creates a virtuous circle, where slowing aging begets demand for further slowing of aging…..this provides a distinctive dynamic to targeting aging compared to treatments aimed at specific diseases,” the paper concludes. The conclusion could lead to economics-based public health policy.

We are now seeing much disparity in the health budgets of states, and large deficit in many developing countries. A formal assessment of what facilities need to be created for the greatest public health returns would optimise the use of scarce funds.

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