By Colin Farrelly
The World Health Organization has designated the decade 2021-2030 as the “Decade of Healthy Ageing”. And the United Nations estimates that the 703 million persons aged 65 years or over in 2019 will double by 2050. I believe the aging of humanity is one of the most significant developments of the 21st century. Population aging is both a success story- one made possible only because of our success with reducing the historically high rates of early and mid-life mortality- but also an unprecedented and pressing public health predicament. Aging is a significant risk factor for disease, frailty and disability. To meet the challenges of population aging the medical sciences must exercise and celebrate the creative epistemic virtues of imagination and idealism. This is the focus of my latest JME article.
The inspiration for writing this JME paper was pure happenstance. When doing research on another project I happened to come across the physician and pathologist Christian Herter’s 1910 Presidential address to the American Medical Association entitled “Imagination and Idealism in the Medical Sciences”. It is a neglected masterpiece! It is just as relevant today as it was in 1910. Progress is possible in the medical sciences, Herter argued, because science is plastic, with new discoveries being made and new interpretations of old facts. And yet, lamented Herter, our lectures and textbooks are conservative and make our minds static by reinforcing the fixity of facts.
Perhaps the most profound insight in Herter’s essay was his observation that the most importance advances in the medical sciences are often made by indirect methods, when researchers were not intentionally looking to treat or cure a disease. In the 100+ years since Herter’s essay the medical sciences’ preoccupation with the study of pathology has only intensified. But I believe this century’s most important advance in public health will likely come from an indirect method- an intervention that modulates the inborn aging process itself, thus increasing the human healthspan vs simply increasing survival by forestalling death.
For the past 15 years I have been following the fascinating field of scientific research known as biogerontology or “geroscience”. This area of research applies insights from evolutionary biology to understand why humans, and other sexually reproducing species, have the lifespan, age of sex maturity, fertility, risks of chronic disease, frailty and disability, etc. that we have. It also studies ways to modulate the aging process in laboratory species such as worms, mice and fruit flies, through interventions like caloric restriction and genetic manipulation. Over the past two decades the prospect of intentionally manipulating the rate of biological aging in humans has gone from realm of science fiction to actual clinical trails, such as the TAME (The Targeting Aging with Metformin) clinical trial in humans. Geroscience inspires us to imagine “adding more life to years” vs just “adding more years to life”. But geroscience remains a somewhat marginal and often misunderstood field within the medical sciences, in part because many do not consider aging to be a disease.
Historically, our imagination fixated, understandably, on ascertaining the causation of pathology, especially those infectious diseases that kept human life expectancy at birth below what we now consider to be “middle age”. Discovering what caused particular infectious diseases, like cholera, helped lead to the sanitation revolution. An understanding of the proximate causes of small pox, polio, diphtheria, tetanus, pertussis, measles, mumps and rubella, etc. helped inspire the imagination needed to develop vaccines to enhance the human immune system beyond what evolution had given us. The idealism of safer environments for humans to live, work and play in, helped make a reality safer food to consume, cleaner water to drink and swim in, safer working conditions, safer vehicles for driving, etc.
When we think of ideals for the medical sciences, our minds turn to cures and treatments for specific diseases. The ideal of a “cancer-free world”, or eradicating HIV/AIDS or COVID-19. In my JME essay I note the successes, but also limitations, of the idealism of disease-control. Unfortunately our fixation on the paradigm of disease control has marginalized what many scientists now believe may prove to be among one the most significant advances in public health this century- an applied gerontological intervention that slows the rate of molecular and cellular decline, thus extending the human healthspan. Using our imagination to target the inborn aging process itself, vs any specific disease of aging, may help us realize the ideal of healthy aging.
Author: Colin Farrelly
Affiliations: Queen’s University
Competing interests: NA
Social media: https://colinfarrelly.com/