Archives of Medicine and Health Sciences

: 2021  |  Volume : 9  |  Issue : 2  |  Page : 187--192

Human well-being, healthy ageing, and syndemics: Inseparable lessons for a sustainable future

Bhaskara P Shelley 
 Department of Neurology, Yenepoya Medical College, Mangalore, Karnataka, India

Correspondence Address:
Prof. Bhaskara P Shelley
Department of Neurology, Yenepoya Medical College, Yenepoya (Deemed to be) University, Mangalore - 575 018, Karnataka

How to cite this article:
Shelley BP. Human well-being, healthy ageing, and syndemics: Inseparable lessons for a sustainable future.Arch Med Health Sci 2021;9:187-192

How to cite this URL:
Shelley BP. Human well-being, healthy ageing, and syndemics: Inseparable lessons for a sustainable future. Arch Med Health Sci [serial online] 2021 [cited 2022 Oct 6 ];9:187-192
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Sustainable Development: Holding Our World in Trust for Our Children – Michael Meacher

 Global Health: The Age of Syndemics

This editorial is my “storytelling” for ushering a sustainable development by harnessing and galvanizing a concept of “collective health.” This must be done without disentangling human well-being, productive human longevity, graceful ageing, ecosystem health of our planet earth, and through the kaleidoscopic lens of the Non Communicable Disorders Syndemics. As an Earth citizen during the era of the COVID-19 pandemic, I do imagine and long for a sustainable future for shared humanity. Imagine if our human intelligence, human will, and collective consciousness is coupled with solidarity for global health, life on Planet Earth would indeed guarantee a future for sustainable humanity and sustainable nature. I hope I am not a 'dreamer.' I hope humanity survives on the Blue planet without the annihilation of the human race. And the world will live as one cosmos. The future is now!

“When one tugs at a single thing in nature, he finds it attached to the rest of the world.” – John Muir

In the Anthropocene era, humanity, as earth citizens, have now a paramount health and other urgent contemporary challenges that would determine our trajectory as a sustainable global civilization, including taking priorities in the stewardship of eco-civilization of our Terra Madre, earth. We are now living through in an unprecedented period in our history with the COVID-19 crisis. Perhaps, I would state that the COVID-19 pandemic will be a critical epoch in our history for us to reimagine human health and public health challenges within the framework of a syndemic perspective.[1] A syndemic perspective conceptualizes the cumulative, intertwined, and synergistic interaction between socioecological and biological factors in the causation of adverse health outcomes. This vanguard concept is indeed a wholesome framework that gives credence to biosocial factors, salutogenesis, with interconnectedness to a life-course epidemiology. To me, “syndemics” is a nonpiecemeal construct that does serve as a model for understanding human well-being, health problems, disease crisis, and healthy life expectancy for the attainment of Sustainable Development Goal for “Good Health and Well-being” (SDG 3). The biosocial concept of health and syndemics reorients our understanding of diseases not as distinct entities in nature, separate from other diseases, and independent of the social contexts in which they are found. Instead, it reconsiders that all of these factors do interact synergistically in various and consequential ways, ultimately imposing a cumulative and substantial impact on the health of individuals and whole populations.

The world is caught in a “syndemic” of chronic disorders at the intersectionality of climate change and human health. This syndemic consists of synergistic interaction of climate change, planetary health, noncommunicable diseases (NCDs), undernutrition, the intricate effects of NCD on healthy ageing, cognitive and mental health, and the potential long-term COVID 19 pandemic. This has been endorsed by the Lancet Commission report giving credence to the “Global syndemic” challenges of obesity, undernutrition, and climate change.[2] Adverse changes in planetary health and climate change are the greatest threat, a silent killer, and an invisible injustice to human well-being and global human health. This climate-health connection has disastrous links to infectious diseases and respiratory, cardiovascular, climate-sensitive health risks, and mental and brain health with resultant neurological and neuropsychiatric disorders.[3],[4],[5],[6]

SDGs must never be seen in isolation but in an integrated, indivisible and collaborative perspective since there are inextricable connections between human health, non-communicable disorders (NCD) related syndemics, and other wider development indices. The other wider determinants do include the human development index, education, gender equity, security, health equity, nutrition & food security, poverty, policies and governance, human rights, dignity, and multiple global environmental changes including climate change. The universal call for action SDGs therefore envisions and guarantees global human prosperity, and transforms the ecological sustainability of our world. The UN 2030 Agenda for Sustainable Development will undoubtedly not end in 2030, but emblematic of a human development mindset that will continue to shape human well-being, healthy longevity, global development, and a sustainability landscape for the rest of the 21st century. At this juncture, it is my viewpoint that human well being and health outcomes must take into account the relationship between exposure to adversity across an overall life course perspective and current syndemic conditions along with the psychosocial health conditions. This would be a holistic sustainable health (care) model for health promotion and disease prevention across the life course of human cycle.

Humanity must collectively recognize the quintessential need for sustainable well-being and have a global charter for reimagining synergistic opportunities to safeguard the health of humans and ecosystem health by reconceptualizing health and disease using a “syndemics lens.” Rebuilding sustainable humanity through the looking glass of Vaisudhaiva Kutumbakam (The World is One Family; A Global Solidarity Initiative), tackling the global disease burden should not be portrayed as a Sisyphean task. I would reiterate that Man's pursuit of hubristic ideologies and scaling the Tower of Babel would meet the “fate of Icarus.” Instead, the syndemic approach to human well-being and to extend human health span and healthy longevity inclusive of ecosystems health would not result in a Pyrrhic victory that we need to abandon this Blue Marble to become a space-faring civilization. Reorienting human systems public health policies and interventions and health-care systems through a syndemic approach would indeed be the strategic bedrock for SDG3, thus safeguarding sustainable humanity for healthy people on a healthy planet, earth.

I would underscore that human ageing is a multifactorial process during the life span and would be myopic to envision ageing strictly within the realms of geriatrics. Rather than targeting a single disease, I reiterate upon the cumulative effect of environmental influences and the syndemics operating on other variables such as demographic, biological, genetics and epigenetic factors, behavioral and social factors, and early and mid-life factors to the process of health span, life span, ageing, and longevity across the life course. In this editorial, I would conceptualize human ageing and the biopsychosocial aspects of healthy life expectancy to be a process that occurs over the human life cycle. It is my opinion that sustainable ageing should not be narrowly focused on health for older adults; instead, we need to reconstruct and broaden the continuum of healthy ageing out of the looking glass of chronological age and Geroscience. The World Health Organization designated the decade 2020–2030 as the “Decade of Healthy Ageing.”[7],[8] Ironically, the COVID-19 pandemic also began at the same time. This unprecedented crisis is exactly why we need to think now about how best to prioritize the needs and risks of elders and manage the health care of sick elders. I would state that the COVID-19 pandemic is also an unforgettable lesson for humanity and a learning opportunity to address human health through the syndemic perspective. The timing is ripe to restructure public health challenges using the “syndemics lens” to formulate prevention and intervention strategies for human well-being. The goal of increasing human health span and the ageing of humanity must be addressed beyond the realm of biogerontology to include a “life course epidemiology,” from the cradle-to-grave perspective. The early-life factors and mid-life social, behavioral, and psychosocial factors as evidenced from the centenarian and longevity studies, especially the Nun study,[9] the Okinawa Centenarian Study (OCS),[10] and the HUNT study,[11] undoubtedly underscore lifestyle and health behavior factors to be associated with entering older age without disease, good mental and cognitive functioning, without frailty. Human longevity is influenced by environment and nutrition too. The healthy life expectancy and Humanity's “Biological Warranty Period” must be conceptualized within a complex, intricate, and intertwined mixture of the Nature–Nurture framework. This should rope in the syndemic perspective without disentangling the contribution of early-life and mid-life risk factors to successful and positive ageing. There must be renewed thrust beyond the scope of preventive geriatrics to successfully integrate preventive medicine, lifestyle medicine, and preventive neurology for a healthy lifestyle and healthy brain ageing (HBA). This integrated approach will be a tangible opportunity that aligns well with the UN 2030 Agenda SDGs for sustainable healthy ageing, and a healthy planet that would safeguard sustainable humanity for the future.

Let me reiterate that “Healthy ageing” is indeed a critical facet of human well-being, which cannot be achieved in isolation by abhorring planetary health and the syndemics of chronic human disorders. Healthy people, healthy ageing, and healthy planet should be ambitious goals in the era of SDGs. A global initiative on healthy ageing that is inclusive of the SDGs will have more thrust to promote healthy ageing, social change, and resilience across generations, not losing sight of the role of the human–environment interaction. Such inclusive public health initiative would be a decisive tool to promote healthy people's longevity and successful ageing as a sustainable goal as well as for sustainable planetary health. We must therefore pledge for “One Planet, One Health, One Future”

 Sustainable Healthy Ageing

“We are going to age, but how we age, that's our choice.” - Dami Roelse

The right to health and healthy life does not start or end at a specific age and I would endorse the “life course approach” to health and healthy life expectancy. Why are we concerned about fostering “Healthy People-Healthy Ageing” initiative as well as a HBA strategy? Undoubtedly, this will revolve around Human capital formation, mental capital and well-being, social capital, and ageing gracefully. I would reiterate that healthy ageing would mandatorily be inclusive of HBA since “brain ageing occurs in tandem with other bodily physiological ageing.”

With this prologue, let me celebrate the human collective knowledge and moralistic action for promoting and supporting healthy ageing through the aegis of United Nations/World Health Organization's initiative “Decade of Healthy Aeging (2021–2030” declared on December 14, 2020. This revolves around the tenet of the 2030 Sustainable Development Agenda and Global Campaign to Combat Ageism. Indeed, it is heartening to take note that India, in global solidarity, did launch the year of Decade of Healthy Ageing (2020–2030). This was proclaimed on October 1, 2020, by Dr Harsh Vardhan, Union Minister for Health and Family Welfare, on the occasion of International Day for Older Persons.

Population ageing or third demographic transition (nicknamed “The Silver Tsunami”) is a formidable demographic phenomenon of the 21st century and unprecedented public health concern in human history. According to World Population Prospects 2019 (United Nations, 2019), by 2050, 1 in 6 people in the world will be over the age of 65, up from 1 in 11 in 2019. The drivers of ageing and increase in the elderly population are mainly contributed by the declining female fertility, and increasing longevity. Taking cognizance of the longevity revolution and being in the era of SDGs, it is indeed pivotal to safeguard the social capital, the best possible mental capital, and well-being of our elderly citizens. The editorial will not to dwell on a public health and health-care system perspective, health care ethics, social and economic consequences of the ageing population, and sustainability challenges of population shrinkage in the urban century. Instead, the focus will be on “healthy life expectancy” and healthy ageing trajectories by explicating lifestyle behavior, various ageing studies, insights from centenarians and supercentenarians, and the need to upskill the knowledge of longevity medicine. I stress that healthy ageing programs will fail unless preventive strategies are incorporated into the larger health-care system. Healthy ageing can not only add years to life, but it adds life to years. The editorial, therefore, underscores facets of “sustainable healthy ageing” through the avenues of preventive neurology, and preventive geriatrics. Undoubtedly, being a cognitive and behavior neurologist with an interest in major neurocognitive disorders (cognitive impairment and dementia), I would emphasize that brain health is fundamental to all health.[12],[13] Therefore, it is imperative to envisage a health literacy perspective and health campaign on brain health, brain-healthy lifestyles, and HBA strategies not only in the ageing population but also from the cradle to the grave to envision “Healthy People-Healthy Ageing 2030” initiative.

 Reimagining Human Well-Being: From Cradle to Grave

“Ageing isn't a problem or disease. Ageing is living.” - Ashton Applewhite

Here, I refer to the life-course perspective of ageing rather than static changes to individuals in the older stages of life. I emphasize a broader perspective that considers ageing to begin at conception, taking into consideration the impact of early and mid-life socioenvironmental conditions and personal, lifestyle choices, and behavioral factors across the life span of human development. Using this cradle-to-grave perspective, a conceptual framework for healthy ageing is possible by advocating the dynamic nature of ageing. The life-course perspective is also crucial in understanding the role of intrinsic (genetic) and extrinsic (environmental) factors in the ageing process.[14] This “health capital” and life-course approach does indeed connect early-life events and factors through the life course (i.e., “the way we live“) to health outcomes occurring much later in adult life and old age.

Natural ageing is a continuous and uninterrupted dynamic process resulting from a cumulative, progressive interaction of Nature Versus Nurture. Broadly, this reflects the interdependency of the role of intrinsic factors (genes) versus extrinsic factors (early to mid-life environment, biosocial, ositive psychobehavioral factors – emotional, personality, motivational, positive life experiences, nutritional, diet-gut microbiome and gut-brain link, and lifestyle behaviors). Increasing evidence does indicate that environmental and lifestyle factors do influence epigenetic mechanisms, such as DNA methylation, histone acetylation, and microRNA expression. It is fascinating to note that both epigenetic mechanisms and lifestyle are tightly linked and modifiable. Therefore, using a life-course approach and lifestyle behavioral interventions could reverse epigenetic ageing, slow biological ageing, and extend health span toward healthy life expectancy.

Healthy ageing strategies inclusive of healthy brain ageing strategies have undoubtedly a direct emphasis and urgent priority to older adults' health and health of ageing populations. Health ageing envisions that “older people live well, age well and have a respectful end of life in age-friendly communities.” Nevertheless, I would like to look backward to move forward for sustainable and healthy human ageing. I would like to dwell on a renewed thrust on health literacy for the “healthy people initiative” that give credence to healthy lifestyle behaviors, brain health, and healthy brain ageing perspective all of which would ultimately dictate cellular health, healthy people, and healthy ageing without dementia. In this context, sustainable healthy ageing should not be narrowly focused on health for older adults; instead, we need to conceptualize healthy ageing out of the looking glass of chronological age life course approach.

I reiterate that healthy ageing is a process that occurs over the life cycle. Therefore, I underscore that a “Healthy people-Healthy ageing” health perspective would mandate a “whole life course approach” from cradle to the grave. A life-course healthy ageing strategy is a multidimensional concept, taking into consideration the biological and behavioral pathways that link various biological, psychological, and social risk factor trajectories during childhood, adolescence, and adult life, to changes in health and disease risk later in life.

What comes to the mind when the term 'ageing' is brought up. Well, at the crux of the biology of ageing it would quintessential to reflect panoply of molecular and regulatory cell biological process that maintains 'cellular health'. Telomeres is postulated as a universal biological clock that shortens in parallel with cellular ageing. In this respect,I would underscore the positive effect of lifestyle variables (diet, nutrition, physical activity) on telomere health, maintenance and dynamics. This captures a holistic wellness concept where a lifestyle and behavioral risk factor-driven approach could exert influences on the epigenetics of human ageing, cellular ageing and telomere biology, cellular genetics, all of which ultimately dictates cellular senescence in health, disease, and ageing.

 Centenarian Studies: Understanding Healthy Ageing and Longevity

“We don't stop playing because we grow old. We grow old because we stop playing.” - George Bernard Shaw

If I were to ask this quixotic question “To live long at 100 years and older or die early at an ideal age,” how would we tackle to answer this question? Some insights to answering this question come from the centenarians, a more elite phenotype of healthy ageing and human survivorship. Centenarians are equipped to reach the extreme limits of the human life span as they seem to have secrets to the art of staying young while growing old. This elite group of cognitively healthy people possess relatively good health, being able to perform their routine daily life, and to escape fatal age-related diseases. The data from centenarians and supercentenarian studies and the Nun study do indeed show the optimism of healthy ageing that is inclusive of successful brain ageing. Centenarians are useful models to explicate the environmental, behavioral, epigenetic, and genetic factors that enhance longevity and decrease susceptibility to vascular and other lethal diseases associated with ageing. The New England Centenarian Study (NECS), a longitudinal study founded in 1994, is exemplary of positive biology, exceptional survival, and life at the extreme limits of longevity. NECS serves as models of healthy human ageing from a life-course biopsychosocial perspective with its underlying genetic (longevity enabling genes) and environmental signatures.

In the Japanese island of Okinawa, there are more people over the age of 100 years than in any other place on earth. Not only do Okinawans live incredibly long and healthy lives, but their lives are replete with happiness, serenity, camaraderie, positive psychology experiences, plenty of activity, healthy lifestyles, with light eating and plenty of exercises, and rest embodying the motivation to live, i.e., “ikigai” means reason/purpose to live (“The Ikigai lifestyle”). Researchers say that the Okinawan secrets include “ikigai, moai, and hara hachi bu” (In Japanese, moai refers to a group of lifelong friends; “hara hachi bu” dietary rule that says that you should eat until you are 80% full – the concept of caloric restriction for healthy ageing).

Elderly Okinawans in Japan have been documented to have the lowest mortality rates in the world from a multitude of chronic geriatric diseases and as a result, enjoy not only what may be the world's longest life expectancy but also the world's longest health expectancy. A “new generation” of centenarians has arisen in Japan, and the total population of persons 100 years old or older reached 32,295 with a centenarian prevalence rate of 25.28 centenarians/100,000 in 2007. The Okinawans are said to be “the world's healthiest and longest-lived people.” In the village of Ogimi,located in the rural north of Okinawa's main island is known as 'village of longevity' since Ogimi has the highest longevity index in the world. The OCS[10] investigated the genetic and lifestyle factors responsible for this remarkable successful ageing phenomenon for the betterment of the health and lives of all people. This elite group of “Dementia free Centenarians,” supernormal centenarians, and supercentenarians are longevity champions who could unlock the mysteries of health or successful ageing. Their life at the extreme limit represents the phenotype of healthy ageing where they have achieved the previously unattainable age of 110 years or more. The traditional Okinawans had healthier lifestyles, consumed a low-calorie diet high in vegetables including sweet potatoes, tofu, seaweeds and soy, low glycemic load diet, and low body mass index (18–22), and had low blood levels of free radicals, low cholesterols, and low homocysteine all of which reduced ageing-related free radical damage, lowered incidence of coronary heart disease and stroke, low cancer, and osteoporosis. Their healthy lifestyle included a healthy diet comprising low caloric intake, high vegetables/fruits consumption, higher intake of good fats (omega-3, mono-unsaturated fat), fish, high fiber diet, and high flavonoid intake (green and herb tea); regular exercise; avoidance of smoking; blood pressure control; and a stress-minimizing psychospiritual engagement. In this study, coronary heart disease and stroke were rare and did not appear clinically until after 100 years of age. The lack of clinical expression of major cardiovascular disease in this elite group does not necessarily indicate the lack of underlying pathology. Autopsy reports on centenarians have indicated several underlying subclinical comorbidities. Nevertheless, these exceptional survivors do seem to be more resilient or better able to delay or adapt to major chronic disease and thus maintain biological function significantly longer.

The Nun study[9] is a longitudinal study of ageing funded by the National Institute on Ageing involving the Teaching Sisters of Notre Dame (USA); 678 sisters were enrolled since 1991 (age 75–102); archived written autobiographies (data on early-life positive emotions; idea density; linguistic skills studied); underwent annual cognitive testing; and by 2003, autopsies were done for 400 deceased sisters. The findings from this study revealed that traits in early, mid, and late life have strong relationships with the risk of Alzheimer's disease, as well as the mental and cognitive disabilities of old age. By studying the nuns' autobiographical writings from their early lives, scientists found that regardless of evidence of Alzheimer's pathology in the brain, sisters who had better language abilities early in life were less likely to exhibit symptoms. Sister Matthia who lived up to the age of 104 years represented the Model of Healthy Ageing despite having Braak and Braak Stage 4 (stage 0 indicates the absence or only sparse appearance of AD pathology; Stages 1 and 2 indicate mild pathological changes; Stages 3 and 4 indicate moderate neuropathology load; and Stages 5 and 6 indicate widespread neuropathology in the brain). Sister Matthia is exemplary of having motivational and cognitive reserve entangled with early positive emotions that led her to be “happy, productive, and vivacious” to the end of her life just weeks short of 105, having “enjoyed more than 100 years of dementia-free life.”

Sister Bernadette had a master's degree, had been teaching elementary school for 21 years and high school for 7 years died at the age of 85 from a massive heart attack. Her brain autopsy had revealed the greatest spread of Alzheimer's disease pathology (Braak and Braak Stage 6) and she had ApoE genetic predisposition (a strong genetic risk factor for AD). Her annual cognitive tests at ages 81, 83, and 84 years revealed high scores on each examination without any evidence of cognitive deterioration. Sister Bernadette thus represented an extreme example: despite a genetic predisposition to Alzheimer's disease (ApoE gene) and an abundance of Alzheimer's disease lesions in her brain, she had preserved cognitive functions and had resistance to the clinical expression of neuropathology, suggesting that the severity of AD pathology did not correlate always with cognitive changes. She had the cognitive reserve which is a measure of the brain's ability to adapt to or compensate for the presence of pathology. The degree of resistance to the clinical manifestation of neuropathology and cognitive reserve is undoubtedly related to life-course events, social factors, nutrition, positive life emotions, intellectual stimulation, education, and lifelong learning. Sister Marcella' “life, cognitive abilities, and longevity were extraordinary;” at 100, her Mini-Mental Status Examination score was documented to be 28/30. At postmortem, she had a remarkably clean, large brain when she died at 101.

These centenarian studies do provide rich insights into a lifestyle for a long healthy life and healthy ageing by the adoption of an early to mid-life life-course perspective. They also appear to have delayed clinically apparent diseases until very late in life that has positive correlates with their health behaviors and health habits.

 Syndemics, Population Health, and Sustainable Development Goal 3

What is the COVID-19 crisis telling us about health systems, the socioecological dynamics of factors influencing health and well-being, and population health? In this context, researchers and public health experts have called for COVID-19 to be considered a syndemic. In a similar vein, I reiterate that the Syndemic framework will have sustainable implications for prevention and multicomponent intervention strategies from a life-course perspective, as well as a new path for global health research. I underscore the vanguard concept of Syndemic framework and public health research emphasizing the domains of social–psychological (i.e., social, political, and ecological factors), psychological– biological, and social–biological interaction to health solutions for SDG3. The syndemics do have a crucial influence on safeguarding the health of people, protecting mental health and brain health, and ultimately healthy life expectancy and productive longevity. I would reiterate that this syndemic approach offers a productive and effective way to strategize multidisciplinary approaches to mitigating human diseases and human “biological warranty period” by understanding how diseases in tandem afflict population health over a continuum in time and place.

The Centenarian studies have established that early-life conditions and mid-life environments do predict healthy ageing and survival to advanced ages. The biopsychosocial determinants for healthy ageing and neurobiological substrates for healthy brain ageing are set in motion during the continuum of ageing 20–30 years earlier during early to mid-life. Healthy ageing is therefore a process that occurs over the life cycle, and our “Healthy People-Healthy Ageing” initiative should not be akin to “closing the stable door after the horse has bolted out.” “Healthy People-Healthy Ageing” initiative should be indoctrinated from school children, school professionals, teenagers, adults, and the elderly by adopting the concept of the “cradle to grave life course approach.”

At the end of this editorial, I hope that I have explicated the answer to the question: What is a life-course approach to health and human capital for sustainable development? I would reiterate that a life-course approach to health, lifestyle (medicine), and health behaviors are inexorably interrelated and intertwined that paves the trajectory for “ageing well” and “productive longevity.” I would state that the physical body and the brain are not in separate rooms. Brain health is fundamental to all health, and I would reiterate that healthy ageing initiatives must be coupled with healthy brain ageing strategies.[13] A life-course approach to health and human capital, healthy people, healthy ageing, and healthy brain Ageing through effective stewardship for a healthy planet coupled with the holistic strategy of a Syndemic framework would certainly pave the way forward in achieving the United Nation's 2030 Agenda for Sustainable Development, i.e., SDG 3 Goal “ensure healthy lives and promote well-being for all at all ages.” Reorienting with the wisdom from the Upanishad, I recall the mantra “Tamaso Ma Jyotirgamaya” (“Lead me from Darkness to Light”) and let me end the editorial with a plea “Let our human solidarity, collective consciousness, our sapience, and collective action lead humanity from dark times to an insightful vision for lighting a sustainable and promising future for human well-being,healthy longevity and planetary health.”

“I like to envision the whole world as a jigsaw puzzle … If you look at the whole picture, it is overwhelming and terrifying, but if you work on your little part of the jigsaw and know that people all over the world are working on their little bits, that's what will give you hope.” - Jane Goodall


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