
Good health across borders in 2030? That's the UN's SDG 3 target. How? Reduction of mortality from non-communicable diseases throughout the globe.
Global health refers to the health of populations from a global perspective which emphasizes the interdependence of health issues across nations and the need for collaborative solutions. It is simply the health of the globe that is the well bring of individuals and populations all over the world. There have been similar definitions by several bodies and organizations. According to the consortium of Universities for global health, “Global health is a field of study, research and practice that places a priority on achieving equity in health for all people’’.
Organizations such as WHO, UN, EU and USAID develop global health programs to save lives, protect local and international communities from diseases while promoting social and economic programs. The main objective of global health is to address the social determinants of health, such as poverty, education, and access to healthcare, as well as creating initiatives that foster partnerships between countries, organizations, and communities to share knowledge, resources, and implement best practices.
There are 3 main eras of global health:
a colonial era which was marked by efforts to protect colonists from tropical diseases from indigenous people.
An international health era which happened in the cold war and was marked by national health efforts in proxy countries to control the spread of epidemics.
The modern era which is the current era marked by professionalization of global health, through significant increase in research, global health training programs and global health capacity-building projects.
The efforts made by global health initiatives have assisted in building local capacities in both low and middle-income countries and parts of sub-Saharan Africa (SSA), as well as empowering communities to take charge of their health outcomes. This includes training healthcare professionals and strengthening health systems, which are essential for building sustainable global health improvements.
The Burden of Non-Communicable Diseases In Sub-Saharan Africa
Non-communicable diseases are the focus of global health as they're are more prevalent in reach and challenging to manage. The major NCD's and their impact in global health at all levels are explained below:
Cardiovascular Diseases (CVDs)
Cardiovascular diseases (CVDs) are emerging as a significant health concern in sub-Saharan Africa (SSA). CVDs are now among the leading causes of morbidity and mortality in this region. The region is experiencing a rapid rise in the incidence of conditions such as ischemic heart disease, hypertension, and stroke. It is estimated that over a million deaths annually in this region are attributed to CVDs, with ischemic heart disease being the leading cause of death among older adults. The prevalence of hypertension in some SSA countries can reach up to 48% of the adult population, which is significantly higher than in high-income countries (Monti et al., 2015).
The rise in CVDs in SSA can be attributed to a combination of traditional and emerging risk factors such as lifestyle habits, genetic and environmental factors and infectious diseases.
Lifestyle Changes: Urbanization and the rise of the middle class have led to lifestyle changes, including increased consumption of unhealthy diets high in salt, sugar, and fats, along with decreased physical activity. These changes are associated with rising obesity rates, diabetes, and hypertension, all of which are significant risk factors for CVDs.
Genetic Factors: There is considerable genetic diversity in SSA, which may influence susceptibility to CVDs. Certain genetic polymorphisms related to cardiovascular health may be more prevalent in African populations compared to those of European descent.
Environmental Factors: The coexistence of undernutrition and obesity, particularly in urban settings, creates a unique risk profile for CVDs. Early life environmental factors, such as maternal undernutrition, can lead to long-term health consequences, including increased susceptibility to CVDs later in life.
Infectious Diseases: The high prevalence of infectious diseases, such as HIV and tuberculosis (TB), also complicates the landscape of CVDs. For instance, diabetes, which is a risk factor for CVDs, is estimated to increase the risk of developing TB threefold, while TB can predispose individuals to diabetes.
Diabetes
Diabetes is increasingly recognized as a significant public health concern in sub-Saharan Africa (SSA), where the prevalence of this non-communicable disease (NCD) is rising alarmingly. Currently, approximately 22 million people in the region are affected by diabetes, with a regional prevalence of about 5.1%. This number is projected to rise to 42 million over the next 15 years, marking the highest global increase in diabetes cases. The disease is affecting individuals at a much younger age compared to more developed regions, with many cases occurring in people aged 40 and below (Pastakia et al., 2017).
The two most common types of diabetes are Type 1 and Type 2 diabetes. In SSA, Type 2 diabetes is more prevalent and is often associated with lifestyle factors such as obesity, physical inactivity, and unhealthy diets. Type 1 diabetes, while less common, also exists and is typically diagnosed in children and young adults. Several factors contribute to the rising incidence of diabetes in SSA:
Urbanization and Lifestyle Changes: Rapid urbanization has led to significant lifestyle changes, including increased consumption of processed foods high in sugar and fat, reduced physical activity, and sedentary lifestyles. These changes are closely linked to rising obesity rates, which is a major risk factor for Type 2 diabetes.
Genetic Predisposition: Genetic factors may also play a role in the susceptibility to diabetes among African populations. There is considerable genetic diversity in SSA, which may influence how individuals respond to environmental risk factors.
Socioeconomic Factors: The rise of the middle class in SSA is associated with changes in dietary habits and physical activity levels. As wealth increases, so does the consumption of unhealthy foods, leading to higher rates of obesity and diabetes.
Early Life Factors: The "thrifty phenotype" hypothesis suggests that early life environmental factors, such as maternal undernutrition, can predispose individuals to metabolic disorders, including diabetes, later in life. This is particularly relevant in SSA, where undernutrition during pregnancy and early childhood is common.
Infectious Diseases: There is a complex interaction between diabetes and infectious diseases prevalent in SSA, such as HIV and tuberculosis (TB). Diabetes can increase the risk of developing TB, and conversely, TB can predispose individuals to diabetes.
Cancers
Cancer is also emerging as a significant public health concern, where the burden of non-communicable diseases (NCDs) is increasing alongside ongoing challenges from infectious diseases. Cancer is becoming one of the leading causes of morbidity and mortality in SSA.
The World Health Organization (WHO) estimates that cancer cases in Africa will increase by 70% by 2030, with the region projected to experience a significant rise in both incidence and mortality rates. Currently, cancers of the breast, cervix, liver, and prostate are among the most common types diagnosed in SSA (Bray et al., 2022).
The types of cancer prevalent in SSA differ from those in high-income countries, largely due to variations in risk factors, lifestyle, and environmental exposures. Breast cancer is the most common cancer among women in SSA, with increasing incidence rates attributed to factors such as urbanization, lifestyle changes, and reproductive factors. Cervical cancer remains a leading cause of cancer-related deaths among women in SSA, primarily due to the high prevalence of human papillomavirus (HPV) and limited access to screening and vaccination programs. Prostate cancer is the most common cancer among men in SSA, with risk factors including age, family history, and possibly dietary influences. Hepatitis B and C infections are significant risk factors for liver cancer in SSA, where these viral infections are endemic.
There are several factors that has contributed to the rising incidence of cancer which include,
Infectious Agents: Certain cancers in SSA are linked to infectious agents, such as HPV (cervical cancer), hepatitis B and C (liver cancer), and HIV (Kaposi sarcoma). The interplay between infectious diseases and cancer is a unique challenge in the region.
Lifestyle Changes: Urbanization has led to lifestyle changes, including increased consumption of processed foods, reduced physical activity, and higher rates of obesity, all of which are risk factors for various cancers.
Environmental Exposures: Exposure to environmental carcinogens, such as aflatoxins (found in contaminated food) and pollution, can increase cancer risk. Occupational exposures in certain industries may also contribute to cancer incidence.
Genetic Factors: Genetic predispositions may play a role in cancer susceptibility among different populations in SSA.
Chronic Respiratory Diseases (CRDs)
Chronic Respiratory Diseases (CRDs) are a significant public health concern in sub-Saharan Africa (SSA). These diseases, which include chronic obstructive pulmonary disease (COPD), asthma, and other chronic respiratory conditions, are contributing to the growing burden of non-communicable diseases (NCDs) in the region. Currently, they are becoming more prevalent in SSA, where they are now among the leading causes of morbidity and mortality. The World Health Organization (WHO) estimates that respiratory diseases account for a significant proportion of NCD-related deaths in the region. For instance, COPD is projected to be the third leading cause of death globally by 2030, and SSA is expected to see a rise in cases due to various factors, including urbanization and lifestyle changes (Ahmed et al., 2017).
The most common CRDs affecting populations include:
Chronic Obstructive Pulmonary Disease (COPD): This is characterized by persistent respiratory symptoms and airflow limitation due to airway and/or alveolar abnormalities. COPD is often caused by long-term exposure to harmful particles or gases, particularly from tobacco smoke and indoor air pollution.
Asthma: Asthma is a chronic inflammatory disease of the airways that can lead to wheezing, breathlessness, chest tightness, and coughing. The prevalence of asthma is rising in SSA, particularly among urban populations.
Interstitial Lung Diseases: These include a group of disorders that cause progressive scarring of lung tissue, leading to respiratory failure. While less common, they are still a concern in certain populations.
Some of the several factors that have been known to contribute to the increasing incidence of CRDs in SSA. Smoking remains a significant risk factor for CRDs, particularly COPD. Also, many households in SSA rely on solid fuels (such as wood, coal, and biomass) for cooking and heating, leading to high levels of indoor air pollution.
This exposure is a major risk factor for respiratory diseases, particularly among women and children. Urbanization and industrialization have led to increased outdoor air pollution, which is associated with respiratory diseases. Poor air quality in cities contributes to the burden of asthma and COPD. The high prevalence of respiratory infections, such as tuberculosis (TB) and pneumonia, can lead to chronic lung damage and increase the risk of developing CRDs. The interaction between infectious diseases and chronic respiratory conditions is particularly concerning especially in SSA.
Mental health disorders
Mental health disorders are increasingly recognized as a significant public health concern in sub-Saharan Africa (SSA). Despite the growing awareness, mental health issues remain underfunded, under-researched, and often stigmatized in many countries within the region. Mental health disorders are prevalent in SSA, with estimates suggesting that approximately 13% of the population may experience a mental disorder at some point in their lives. Common mental health conditions include depression, anxiety disorders, schizophrenia, and substance use disorders (Charlson et al., 2014). The burden of mental health disorders is exacerbated by various factors, including poverty, conflict, and the impact of infectious diseases such as HIV/AIDS and tuberculosis.
The most common mental health disorders affecting populations include:
Depression: This is one of the leading causes of disability worldwide and is particularly prevalent in SSA. Factors such as poverty, unemployment, and social isolation contribute to the high rates of depression in the region.
Anxiety Disorders: These include generalized anxiety disorder, panic disorder, and post-traumatic stress disorder (PTSD). The prevalence of anxiety disorders is rising, particularly in populations affected by conflict and displacement.
Schizophrenia and Psychotic Disorders: These disorders are often misunderstood and stigmatized in SSA. Access to appropriate treatment is limited, leading to significant morbidity and disability.
Substance Use Disorders: The misuse of alcohol and drugs is a growing concern in SSA, contributing to mental health issues and exacerbating existing conditions.
A vast number of factors contribute to the increasing incidence of mental health disorders in SSA. For instance, poverty, unemployment, and lack of access to education are significant risk factors for mental health disorders. Also, economic instability can lead to increased stress and mental health issues. Many countries in SSA have experienced prolonged periods of conflict, civil unrest, and violence. Exposure to trauma and violence is a significant risk factor for developing mental health disorders, particularly PTSD and depression.
The 10/90 Gap Concept
The 10/90 gap concept refers to the disparity in global health research funding, where only 10% of the total funding is allocated to diseases that predominantly affect low- and middle-income countries (LMIC), while 90% is directed towards diseases that primarily impact high-income countries (HIC). This further explains that the majority of global health research funding is focused on conditions that are less prevalent in LMIC, despite these countries bearing a disproportionate burden of diseases. In LMIC, the 10/90 gap is usually less favorable as it is negatively impacted by the social determinants of health, such as poverty, education, and access to healthcare, thereby increasing the burden of disease as well as limiting the capacity of researchers in these countries to engage in global health research (Addo-Atuah et al., 2020).
Implications of The 10/90 Gap On Global health
The 10/90 gap has significant implications for health research in developing countries, where much of the population faces a high burden of diseases yet receives minimal research funding. The following are some key impacts:
Limited Research on Local Health Issues: Due to the disproportionate allocation of research funding, many diseases prevalent in developing countries, such as malaria, tuberculosis, and HIV/AIDS, receive insufficient attention. This lack of research hampers the development of effective treatments and interventions tailored to the specific health challenges faced by these populations.
Inadequate Health Infrastructure: The 10/90 gap contributes to the underdevelopment of health research infrastructure in some areas. With limited funding, there are fewer resources for training researchers, conducting studies, and establishing research institutions. This results in a cycle of dependency on external funding and expertise, which may not always align with local health priorities.
Poor Health Outcomes: The lack of targeted research leads to inadequate understanding and management of diseases that disproportionately affect populations especially in Sub-Saharan Africa. Consequently, this contributes to higher morbidity and mortality rates from preventable and treatable conditions, exacerbating health disparities.
Neglect of Non-Communicable Diseases (NCDs): While infectious diseases have historically dominated the research agenda, there is a growing burden of non-communicable diseases (NCDs) in Nigeria and Sub-Saharan Africa. The 10/90 gap means that research on NCDs, which require different approaches and interventions, is often overlooked, further complicating health challenges in the region.
Impact on Policy and Practice: The lack of robust research data limits the ability of policymakers to make informed decisions regarding health interventions and resource allocation. This can lead to ineffective health policies that do not address the actual needs of the population.
Global Health Inequities: The 10/90 gap perpetuates global health inequities, as researchers and health professionals may struggle to compete for funding and recognition in the global health arena. This can hinder the development of local expertise and innovation in addressing health challenges.
Final Thoughts
The application of the 10/90 gap involves prioritizing local health issues, strengthening research capacity, fostering partnerships, advocating for policy changes, utilizing community engagement, addressing social determinants, and promoting equity in global health initiatives. These efforts can significantly improve health outcomes and reduce disparities globally.
References
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Ahmed, R., Robinson, R., & Mortimer, K. (2017). The epidemiology of noncommunicable respiratory disease in sub-Saharan Africa, the Middle East, and North Africa. Malawi Medical Journal, 29(2), 203-211.
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