REVIEW ARTICLE
Year : 2022 | Volume
: 1 | Issue : 2 | Page : 52--58
The changing global ageing demography and africa perspective: Implications for future pandemics
Abiodun Bamidele Adelowo
Department of Medical Services, Office of the Vice President, State House Abuja, Nigeria
Correspondence Address:
Abiodun Bamidele Adelowo
Department of Medical Services, Office of the Vice President, State House Abuja
Nigeria
Abstract
Despite pockets of incidences in different places, from all indications, the world might has experienced the worse phase of the COVID-19 pandemic. We must however admit the obvious – the pandemic caught the world poorly prepared. The relatively high case-fatality rates and socioeconomic losses from the pandemic could have been effectively mitigated assuming the global healthcare systems were more proactive in their preparedness. However, there is no time to cry over spilled milk. We must quickly learn our lessons and prepare for future disease outbreaks. Another pandemic in the future without adequate preparedness may be too grievous to the fragile interconnected global healthcare and economic systems. The objectives of the article are to briefly discuss the global ageing population and the role such phenomenon might have played in the recent global COVID-19 outbreak and may play in future disease outbreaks, especially in Africa. Accordingly, a review of related online full articles published from 2000 to 2022 from reliable scientific search engines was done. Results revealed that the world is presently experiencing a change in age demography to older age groups, and such phenomenon might have played a significant role in the different COVID-19 incidence and case-fatality rates that were experienced by different regions of the world. Due to the fast-changing age demography in Africa, the continent might suffer the most unfavourable outcomes from future pandemics. Stakeholders must closely monitor the fast-changing age demography in Africa and institute evidence-based health-promotional measures that will adequately prepare the continent for future disease outbreaks.
How to cite this article:
Adelowo AB. The changing global ageing demography and africa perspective: Implications for future pandemics.J Niger Acad Med 2022;1:52-58
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How to cite this URL:
Adelowo AB. The changing global ageing demography and africa perspective: Implications for future pandemics. J Niger Acad Med [serial online] 2022 [cited 2023 Jun 2 ];1:52-58
Available from: http://www.jnam.com/text.asp?2022/1/2/52/365599 |
Full Text
Introduction
The tail end of the year 2019 will forever go down in the history of the world as one of the darkest moments in recent human history. In December 2019, there was an outbreak of COVID-19 in Wuhan, China, and in a few months, the disease had spread to all regions and corners of the world. For the next 2 years, this highly infectious disease kept the world on its knee, forcing most human socioeconomic activities to either slow down or completely short down. In just two years and a few months, precisely from December 2019 to June 2022, COVID-19 had been diagnosed in 533,816, 957 cases, resulting in 6,309,633 case fatalities.[1]
Although many countries, especially the developed countries, can boast of fairly robust healthcare systems, the COVID-19 pandemic-induced global economic losses and the unprecedented disruption of human activities pointed in only one direction. The world was unprepared, or at best, poorly prepared for the COVID-19 pandemic. A mistake that must not be made ever again. Another episode of a major global disease outbreak(s) without proper preparedness and adequate proactiveness might be too fatal as the world’s fragile economic and security systems may never recover.
Compared to the rest of the world, Africa suffered the least from the COVID-19 pandemic. The African continent recorded the least incidence and case-fatality rates from the deadly infectious disease. According to the records of the WHO, as of June 2020, only 9,053,205 confirmed COVID-19 cases were recorded in Africa, compared to 222,913,637 cases in Europe; 159,605,214 cases in the Americas; 62,148,182 in Western Pacific, 58,260,872 in South-East Asia; and 21,835,083 in Eastern Mediterranean.[1] These results were surprising to many because it has been predicted by some that Africa might record one of the highest morbidity and mortality rates from COVID-19; and dead bodies might litter the streets of some African countries.[2] Many explanations have been proposed as the reasons for the disparity in the COVID-19-related morbidity and case-fatality rates as witnessed by different regions of the world. Most especially, questions have been asked on why the least prepared continent – Africa, seems to have suffered the least from the recent COVID-19 pandemic.
One major factor that might explain the different COVID-19 incidence, hospitalization, and case-fatality rate in different regions of the world is the changing global ageing demography. A deeper understanding of this phenomenon and its public health implications might explain the reason why Europe and America seem to have been massively hit by the COVID-19 pandemic, and why Africa seems to have suffered the least. Furthermore, global public health policymakers and practitioners will also need such information to be able to properly position the world’s healthcare systems and adequately prepare for future disease outbreaks, especially in Africa.
The Epidemiology of the Global Changing Ageing Population
Life expectancy is increasing at an alarming rate globally, and a good number of the global population are presently 60 years and above.[3],[4] Never before in human history has a large number of people lived to older (≥ 60 years) or oldest (≥ 80 years) age, as noticed in this generation.[5] People who are ≥ 60 years were only 8% (200 million) of the world’s population in 1950, it rose to 382 million in 1980, to 11% (760 million) in 2011, then to 900 million in 2015, and to 962 million by 2017.[4],[6],[7]
The number of these older adults (≥ 60 years) population is expected to continue to increase globally; it will nearly double to around 1.4 billion by 2030, and nearly triple to around 2.1 billion (22% of the world’s population) by 2050, and most of the increase will be recorded in Africa and in developing countries.[4],[6],[7] Similarly, in 2003, the global population of people who are ≥ 65 years was only 35.9 million, this rose by 24.7% to 44.7 million by 2013, and is expected to rise to more than double, to around 98 million by 2060 [Figure 1].[8]{Figure 1}
The increasing global older adult population is occurring simultaneously in all countries and communities of the world. According to the projections of the United Nations, all of the countries of the world or any geographical area with at least 90,000 inhabitants, are presently experiencing and will continue to experience an increase in the proportion of persons aged ≥ 60 years.[7] About 16.5% of the world’s population is presently or will be ≥ 60 years by 2030, this is expected to rise to about 22% by 2050.[5] In fact, the percentage of people who are ≥ 60 years may have already exceeded 16.5% of the total population in some (if not most) developed European and North American countries.[5] By 2050, the percentage of people that are ≥ 60 years is expected to rise to 35% of the population in Europe, 28% in Northern America, 25% in Latin America and the Caribbean, 24% in Asia, 23% in Oceania, and 9% in Africa.[7]
Also, by 2030, the global number of older persons (≥ 60 years), is expected to be more than that’s of children (< 10 years) (1.41 billion versus 1.35 billion); while by 2050, the number of people worldwide who are ≥ 60 years is projected to be more than that’s of adolescents and youth (at ages 10–24 years) (2.1 billion versus 2.0 billion).[7],[9] This is the first time in human history that the world would likely have more older people (≥ 65 years) than children (< 5 years), regardless of their geographical location and socio-economic status.[10],[11]
Even among the oldest population (≥ 80 years) of the world, life expectancy is increasing. Presently, one in every eight older persons (≥ 60 years) are aged 80 years and above. The percentage of this age group (≥ 80 years) increased from 0.6% (15 million) of the world population in 1950 to around 1.6% (110 million) in 2011.[5] From 2017 to 2050, the global population of persons aged ≥ 80 years is projected to increase more than threefold, rising from 137 million to 425 million, which will be about 4% of the world population by 2050.[12],[13]
These statistics suggest that almost one-sixth of the present global population is already ≥ 60 years and their percentage and absolute number are increasing daily. From all indications, the global older adult (≥ 60 years) population may increase to more than one-fifth of the world population and about one-third in many developed countries by 2050. This high and still rising percentage of global older adults has a lot of implications on the present and future disease profiles and disease outbreaks [Table 1] and [Table 2].{Table 1} {Table 2}
The Changing Aging Population in the Developing Countries and Africa
For decades, the health and socio-economic systems in developing countries have faced numerous challenges – ranging from poor infrastructures, low Gross Domestic Products (GDP) per capita, high burden of preventable communicable diseases, unstable political environment, security instability, etc. Another challenge with probably greater magnitude is now emerging. The population in most developing countries is fast ageing, at a greater pace than the developed counties, and quicker than the available resources.[7] For decades Africa has always prided itself as the continent with the youngest population. The present median age of people living in Africa is only 19.7 years, which has been projected to rise to just 26.4 years by 2050.[5]
Only 5.5% of Africans are presently 60 years and above, this is projected to increase by only 4.3% (i.e., to 9.8%) by 2050, compared to Asia and Latin America (which will increase from 10% to 25%), and Europe and North America (which will increase from 20% to 30%) within the same period.[5] Furthermore, over 41% of the country with the largest population in Africa, Nigerian, is presently under 15 years. Only about 5% (about 10 million) of Nigerians are presently 60 years and above, while the majority of the Nigerian population lies between the ages of 0 to 14 years, with a median age of only 18.1 years.[14] Indeed, the black continent is occupied by mostly young people. However, these statistics are fast changing.
Although the global changing ageing population was first noticed in the high-income developed countries, the phenomenon is fast catching up with Africa and with most low- and middle-income developing countries.[4] It now appears that the developing countries are “getting old faster before they get rich”.[5] From all indications, the largest and the most dramatic increases in absolute numbers of older persons are expected to occur in Africa and most developing countries.[6] By 2030, the percentage of people who are ≥ 65 years in developing countries is expected to rise by as much as 140% from its present level.[15] While by 2050, about 80% of all the global citizens that will be 60 years and above will likely be living in Africa and developing countries.[4],[7]
Even now, the present absolute number of older adults (≥ 60 years) in sub-Saharan Africa (SSA) alone double that’s of the entire population of northern Europe, and this figure is expected to rise significantly faster than anywhere else in the world and will increase from around 46 million in 2015 to around 157 million by 2050.[10] Furthermore, between 2017 and 2050, the population of people aged ≥ 60 years in 25 countries of the SSA (including Nigeria) is projected to increase by more than threefold, while in four SSA countries (Malawi, Rwanda, Uganda, and Zimbabwe), the number of older persons will quadruple over the same period.[7] In addition, the speed or pace of increase in the absolute number of the older persons has been projected to be fastest in Africa (compared to other continents), where the absolute number of these older citizens will increase by more than threefold, from 69 to 226 million between 2017 and 2050, then to 716 million by 2100.[7]
No other region of the world will experience such growth at such a pace. Furthermore, the most rapid increase in the absolute number of older persons in Africa will be expected in Eastern (such as Kenya), Western (such as Nigeria), and Central (such as Cameroon) African countries, while most of the Northern and Southern Africa countries will only experience only modest absolute rise within the same period.[5] The pace of increase will be so fast that most African (and some of the developing) countries will have much shorter periods to react or adjust to the demographic transition.
There may not be enough time to formulate the necessary policies and built needed infrastructures to meet the health and socioeconomic needs of the anticipated high number of the older population.[5] By implication, although Africa will likely have the highest absolute number of older adults (≥ 60 years) by 2050, the continent may likely not have enough time, finance, infrastructure, and other resources to manage the anticipated negative health and socio-economic impacts that may arise from such occurrence.
Epidemics Implication of the Global Ageing Population: COVID-19 as a Case Study
The changing global ageing demography to a much older population is regarded as probably the most important public health, medical and socio-demographic problem of the 21st century.[9] This is partly so because there exists a positive correlation between increasing age and declining health, resulting in gradual dysfunction in virtually all physiological processes in the body. The ageing process negatively impacts people’s health primarily by causing a gradual and progressive loss in the body’s ability to adjust appropriately to behavioural and environmental assaults. This with time results in progressive difficulty in maintaining the internal milieu and homeostasis of the body.[16]
Furthermore, the increasing wear and tear, and production of free radicals and pro-inflammatory biomarkers that are associated with advancing age, tend to create cascades of pathophysiological and psychosocial changes in the body. Some of these multiple, gradual, and often simultaneous age-related changes in the body include – the development of systemic chronic inflammation (SCI); multiple molecular and cellular damages and degradation; increase in the rate of incomplete or error in replication, repair, or destruction of cells; dysfunctional immune regulation; decrease neuroimmunoendocrine communication, and increase organ degeneration and atrophy. All these health-damaging events often increase people’s vulnerability or susceptibility to diverse environmental trauma, pollutions, infections, and other forms of stress.[10],[17]
In most cases, these cascades of age-induced changes in the body eventually result in the development of varying degrees of frailty, disabilities, and chronic non-communicable diseases (NCDs) – such as hypertension, heart diseases, diabetes mellitus, stomatitis, neurodegenerative syndromes (like Alzheimer disease), benign prostatic hyperplasia, some cancers, many autoimmune diseases, and other chronic diseases of aging (CDA).[18],[19],[20] In addition, the dysfunctional immune regulation and decreased neuroimmunoendocrine communication that are often associated with advancing age often result in increased susceptibility to and severe forms of many infectious diseases. Increased susceptibility to some infectious diseases by a large number of people in a community coupled with a ‘favourable environment’ are often the most important factors that result in disease outbreaks – be it epidemics or pandemics.
Using the COVID-19 pandemic has a case study – multiple studies highlighted three socio-demographic factors as very critical in the relative high infectivity, hospitalization, and case-fatality rates of COVID-19 that were recorded in some communities. These factors were older age (especially ≥ 60 years), male gender, and ethnic minority groups (especially the black race).[21] Out of these, older age is arguably the most important factor. Studies suggested that the higher the age, the higher the probability of developing COVID-19. A study that was done among 1, 591 confirmed COVID-19 Italians observed that the median age of the patients was 63 years.[22] Other observational studies that were done on confirmed COVID-19 patients in China also revealed the median ages of 47, 49, 50, and 55.5 years from different studies.[22]
Different studies also associated high hospitalization and case-fatality rates in COVID-19 cases with older age groups. A study that was done among confirmed COVID-19 cases in China noticed that almost 50% of hospitalized patients (due to “refractory” COVID-19) were 60 years and above.[23] Another China-based study noticed a median age of 56 years among the 138 COVID-19 cases that were hospitalized for different COVID-19-related complications.[22] A study that was done in 12 New York City area hospitals among 5,700 hospitalized patients, all with severe forms of COVID-19, noticed a median age of 63 years.[24] While a meta-analysis revealed that the most important determinants of mortality in conformed COVID-19 cases in China were advanced age (above 60 years) and age-related underlying chronic diseases.[22]
Since advancing age is associated with dysfunctional immunity and poor immune resilience, infectious diseases (that have the potential to cause outbreaks) will almost always take advantage of a high percentage of older adults in the community to strike. Thus, the relatively higher infectivity, hospitalization, and case-fatality rates of COVID-19 that were recorded in many European and North American countries may likely have resulted from the high percentage of older adults in their communities. While the relatively lower infectivity, hospitalization, and case-fatality rates of COVID-19 that were recorded in most African countries may likely be due to their younger population.
However, since about 22% of the world’s population and 35% of some developed nations will be 60 years and above by 2050, it is only logical to predict that the world will experience more disease outbreaks (possibly in pandemic forms) in the nearest future. Furthermore, since Africa will house the highest absolute number of older adults (≥ 60 years) by 2050, it will also be logical to predict that the black continent will soon lose its ‘young population immunity or advantage’ and may experience frequent and possibly severe epidemics in the nearest future. By implication without adequate preparation the next major disease outbreaks might be too devastating to the fragile and ill-prepared healthcare systems and economy of most African countries; with a ripple effect on the interconnected global economy and peace.
Africa and the Need to Prepare for Future Disease Outbreaks
Although present statistics strongly suggest that Africa is fast losing its ‘young population immunity or advantage,’ it appears the black continent is the least prepared for its possible health and socio-economic implications. In contrast to other nations of the world, issues around ageing population are barely considered by most policymakers in Africa. If considered at all, they are perceived at best as marginal to, and at worse a distraction from the major and pressing national and subnational developmental, economic, and security issues.[5] There seems to exist a weak political will to take appropriate proactive measures among leaders in Africa. This is despite the formal declaration of commitments to take appropriate actions by most African nations during the United Nation’s Madrid Plan of Action on Ageing and the African Union (AU)’s Policy Framework and Plan of Action on Ageing.[5]
Because other developmental challenges in Africa will likely persist by 2050, the black continent may be unable to surmount the challenge that the additional health and socioeconomic burdens that a ageing population might bring to the table. The levels of healthcare and socioeconomic developments in most African countries may not be robust enough to effectively manage the anticipated rise in the absolute number of the older population and its associated increased prevalence of chronic diseases of age (CDA) (such as hypertension, type 2 diabetes mellitus, cardiovascular diseases, and some cancers), frequent outbreaks of infectious diseases, and high prevalence of age-related frailties/disabilities. Such situations, if not well managed, might further crumble the fragile and infantile healthcare and socioeconomic systems in Africa. A situation that may be unsustainable in the long-term and may even reverse all the hard-earned developmental indices that the continent has painstakingly accrued over the years.
Regardless of the present developmental challenges confronting Africa and the developing world, the issues around the ageing population must be recognized and prioritized as a vital developmental issue for the future survival of Africans. If well managed, it carries enormous developmental potentials, if not, it might be difficult for Africa, to recover from its potentially catastrophic effects for many years. Unfortunately, Africa and the developing world do not have the luxury of time to take necessary actions. It took most developed counties decades, and sometimes a century, to adjust to their demographic transition. For instance, it took the population aged ≥ 65 years in France more than 100 years to rise from 7% to 14%, which is more than enough time for the country to put the necessary adaptive measures in place. However, it will take Africa and many developing countries only a few decades to achieve similar demographic change.[3]
Consequently, African and developing nations need to act fast and decisively. The issues around the ageing population cannot and must not wait any longer. Contrary to popular opinion, the issue of ageing cannot be ignored or postponed. One of the best strategies that Africa and the rest of the world need to adopt is to adequately prepare for a future full of older citizens. This can be done through immediate and strategic investment in the education and health of the citizens throughout their life course.[5] A well-educated population will appreciate and understand the challenges ahead and make adequate individual and group preparation to effectively avoid or manage future disease outbreaks. More people must also be educated on how to achieve healthy ageing (regardless of their present age group or health status), and how to manage their peculiar health needs in old age.[3]
Secondly, there is a need to institute health promotional policies and programs that will optimize the immune resilience and functional capacities of most people, starting from a young age. Such measures will likely ensure that the immune system and functional capacities of most people are primed and resilient enough to withstand and mitigate external assaults from infectious diseases, thereby preventing or mitigating the effects of possible future disease outbreaks. From the available evidence, the best-known measure to increase people’s immune resilience and optimize their functional capacities is for them to constantly engage in healthy lifestyle practices throughout their lifespan, starting from their younger age.[25],[26]
Evidence-based healthy lifestyle practices that can promote strong immunity and optimal functional capacity up to old age include – regular consumption of whole food plant-based diets; engaging in adequate physical activity, restorative sleep, good stress management, and good social connectedness; and avoidance of substance abuse (such as tobacco use).[25],[26] Adequate investment and resources must be channeled in these directions by all stakeholders – right from the individual, community, and national levels.
Furthermore, stakeholders should prioritize certain policies and programs for the older persons, including intergenerational knowledge transfer, better access to healthcare services, improved social pension programs, stronger support for informal and family-based support systems, and greater access to healthy nutrition.[5] Finally, government and all stakeholders must continue to closely monitor the fast-changing age demography and disease outbreaks patterns in Africa and the rest of the world through well-funded research works, and promptly implement the recommendations from such ventures.
Conclusion
The scientific world learned a lot from the recent COVID-19 pandemic. The susceptibility, spread, and severity of the disease positively correlated with the rising global ageing phenomenon. Africa was speared of the relatively high incidence, hospitalization, and case-fatality rates from COVID-19 partly because of her relatively young population profile. This will likely change in a few years from now, and Africa will most likely record the highest absolute number of older adults (≥ 60 years) by 2050, compared to the rest of the world. A high number of older adults (most of whom may have age-related immune dysfunctions and multiple chronic diseases of age) coupled with a ‘favourable environment’ (largely due to climatic change) in Africa are perfect opportunities for multiple disease outbreaks.
Although we cannot stop the global ageing population phenomenon, we can effectively control it by optimizing the human functional capacities and immune resilience to possible future disease outbreaks. This can be done by implementing evidence-based measures that promote healthy lifestyles and sustainable positive behavioural changes, right from a young age. Such proactiveness and preparedness will likely translate to better ability of the immune system of the majority of people to resist or control future major disease outbreaks.
Financial support and sponsorship
Nil.
Conflict of Interest
The author declares no conflict of interest.
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