Abstract
Health inequalities remain a central challenge in public health and are often shaped by social and economic conditions. However, in many cases, geographic determinants are overlooked despite having a significant impact on population health. Some geographic determinants include altitude, climate, terrain, and environmental conditions. The altitude of residence can impact health in various ways; areas located at high altitudes face challenges such as living in zones with low oxygen levels and the effects of hypoxia. Climate has a direct effect on health; heatwaves can affect agricultural production, causing food shortages and nutritional problems. Similarly, geographic isolation, limited access to water, air pollution, and biodiversity loss contribute to region-specific health risks. This paper highlights the importance of incorporating geographic determinants into public health frameworks to inform the development of context-sensitive and equitable interventions. Recognizing the influence of geography is essential to reducing health disparities and improving outcomes for populations living in environmentally vulnerable areas.
Keywords
Significance for Public Health
Public health seeks to address health disparities by tackling the social determinants of health, aiming for effective interventions to resolve them. However, geographic determinants play a fundamental role in health status and are often relegated to the background or overlooked. Understanding the role of geographical determinants will allow the formulation of more effective public health policies adapted to each environment, especially in remote communities
Introduction
In public health, discussions on health inequalities have traditionally emphasized social determinants such as income, education, and access to healthcare. 1 While these factors are undeniably critical, a crucial dimension remains insufficiently explored: geography. 2 Gaeographic variations are not only socially and ecologically relevant but also carry direct implications for clinical outcomes and public health planning. The influence of geography in medical practice must be taken seriously—not only to accurately measure racial and socioeconomic disparities, but also to design effective, context-sensitive reforms that reduce them. 2 For instance, being poor in the Amazon region, with access to biodiversity, freshwater, and relatively stable environmental conditions, differs profoundly from being poor in the high Andes, where hypoxia, extreme temperatures, and nutrient-poor soils compound health vulnerabilities.3,4 This same principle applies globally: it is not the same to belong to an indigenous group like the Ogiek tribe in the forests of Kenya as it is to be a Maasai living on the plains of the Maasai Mara. 5 The Ogiek benefit from more favorable ecological conditions such as water access, fruits, and cultivable land while the Maasai must contend with arid terrain, dependence on pastoralism, and prolonged periods of water scarcity. 6 In both cases, poverty exists, but geography fundamentally shapes the risks, resources, and resilience of each population.
Evidence shows that place of residence profoundly influences both access to healthcare and exposure to risk, thereby shaping health outcomes in significant ways. 7 Marginalized populations residing in remote, high-altitude, arid, or polluted urban areas often encounter structural barriers such as limited healthcare infrastructure, heightened environmental hazards, and substandard service quality. 8 Furthermore, these spatial disparities frequently intersect with racial and socioeconomic inequities, reinforcing cycles of deprivation and poor health. 9
There are four principal types of relationships between health determinants and geographical space: physical health determinants, anthropogenic pollution, nutritional processes, and behavioral habits. 10 Within these categories, key elements include water availability and contamination, air quality, and broader environmental conditions. Notably, one critical yet often overlooked factor is the impact of residential altitude on human health.10,11
These considerations underscore the urgent need to integrate geographic determinants into public health discourse. Current policies frequently neglect these spatial variables, leaving high-risk populations underserved and thereby exacerbating existing health inequities. Recognizing and addressing the role of geography is essential for designing more equitable and effective health interventions.
Geographic Determinants of Health
Geography plays a fundamental role in shaping the conditions in which people live, yet it is often integrated as a secondary factor within broader health determinant models, such as the Dahlgren and Whitehead model or the Canadian Health Determinants Framework. Geographic determinants directly influence health outcomes in various ways. For instance, individuals residing at high altitudes are more prone to hypoxia-related conditions, while those in tropical regions face heightened risks of vector-borne diseases and parasitic infections.12,13 The physical environment, coupled with geographic isolation and uneven access to healthcare services, intensifies the effects of social determinants and deepens health disparities.
Vine et al underscored the need for public health frameworks to incorporate geographical factors into disease prevention and healthcare access. 14 Integrating these determinants into public health planning would allow for more context-specific interventions that better address health inequalities. Just as social and economic factors shape health outcomes, geography must also be considered.
Specific Geographic Risks and Suggested Interventions
Impact of Altitude on Health
Prolonged exposure to high-altitude hypoxia presents a range of health risks. Living in low-oxygen environments has been associated with increased rates of suicide, cardiovascular disease, and cerebrovascular events (strokes). 15 Furthermore, evidence suggests that children raised in high-altitude regions may experience impaired cognitive development due to sustained hypoxic stress during critical periods of brain maturation. 16 The cumulative effects of hypoxia can ultimately hinder both the health status and economic productivity of these populations. Compared to individuals residing at lower elevations, those living at high altitudes may encounter greater difficulties in achieving optimal cognitive and physical development.
Mental health is also adversely affected by altitude. Both short- and long-term emotional and psychological disturbances have been reported, including mood fluctuations, heightened psychological stress, and a higher prevalence of depressive symptoms. Additionally, individuals residing at high altitudes frequently report poorer self-perceived health outcomes. 17
Nutritional deficiencies are another significant concern in high-altitude regions. Limited access to a diverse range of nutrient-rich foods often results in carbohydrate-heavy diets that lack adequate proteins and essential micronutrients.18,19 These nutritional limitations contribute to long-term health issues, including stunted growth and anemia, further impairing the health potential of populations in these areas.
Additionally, iodine deficiency, exacerbated by the low iodine content of high-altitude soils, is particularly concerning for pregnant women. Long-term exposure to iodine-deficient environments may lead to hypothyroidism and, in severe cases, cretinism in newborns—a condition characterized by irreversible developmental delays and cognitive impairments. 20 Implementing iodine supplementation strategies and comprehensive nutrition education programs is vital to prevent these adverse outcomes.
Other aspects affected by altitude include eye health. Exposure to high-altitude conditions is associated with a range of ophthalmic effects. Short-term consequences include high-altitude retinopathy, variations in corneal thickness, and photokeratitis, while long-term exposure can contribute to the development of pterygium, cataracts, and dry eye syndrome. 21
Water Access and Desert Regions
Access to safe and sufficient water is a fundamental determinant of health, particularly in arid and desert regions where scarcity poses critical threats to human survival and well-being. In such environments, limited water availability increases the risk of dehydration, heat-related illnesses, and food insecurity. Populations living under these conditions face compounded challenges, including famines, infectious diseases, and malnutrition, largely due to inadequate irrigation for agriculture and limited access to potable water.22 -25 This situation contrasts with regions such as North and South America, where water resources are generally more abundant, though increasingly threatened by the impacts of climate change.
According to estimates from the World Health Organization (WHO), approximately 1.6 million deaths annually are associated with poor access to water and inadequate water security. Of these, nearly 60% are attributed to infectious diseases—most notably diarrhea, schistosomiasis, trachoma, and intestinal helminth infections. Moreover, early-life exposure to diarrheal diseases has been linked to long-term consequences in children, including malnutrition and impaired cognitive development observed between 6 and 9 years of age. 26
Beyond physical health, water scarcity also exerts a profound impact on mental health, particularly in rural areas. The economic hardship caused by crop failures, combined with the social stigma of poverty and the isolation often experienced during prolonged droughts, can lead to significant psychological distress. Chronic stress from the daily search for potable water, fears of waterborne diseases or flooding, and the cumulative mental burden of environmental instability contribute to elevated rates of anxiety and depression. In many cases, these pressures prompt internal or cross-border migration, which in turn introduces additional psychosocial stressors and exacerbates the mental health burden. 27
To mitigate these impacts, it is essential to implement effective water governance strategies. This includes the development of resilient water management systems, adoption of efficient irrigation technologies, and the integration of climate adaptation policies tailored to the needs of water-scarce regions.25,28,29
Air Quality and Pollution in Urban Areas
Air quality is another vital geographic determinant of health, particularly in densely populated urban areas. Exposure to poor air quality, driven by industrial emissions and vehicular traffic, has been linked to increased rates of respiratory diseases, cardiovascular conditions, and premature death.30,31 In 2019 alone, air pollution caused around 6.7 million deaths, of which 85% are attributable to non-communicable diseases such as ischemic heart disease, stroke, lung cancer, asthma, and chronic obstructive pulmonary disease (COPD). 32 The burning of fossil fuels, along with deforestation and urban sprawl, has worsened air pollution globally, particularly in rapidly growing cities. Efforts to create green spaces, regulate industrial emissions, and promote sustainable public transportation are necessary to reduce the health burden caused by air pollution.
Biodiversity and Ecosystem Risks
Biodiversity plays a crucial role in maintaining health, both directly and indirectly. Diverse ecosystems offer natural protection against environmental risks, such as disease transmission and pollution. For example, exposure to a rich variety of microbes in biodiverse environments may promote a healthy microbiota, which strengthens the immune system and protects against allergies and autoimmune diseases.33,34 However, human encroachment on natural habitats, often through agricultural expansion, has increased the risk of viral spillovers from wildlife to humans, as seen in recent zoonotic outbreaks. The destruction of ecosystems at the agricultural frontier, combined with global climate change, increases the likelihood of such events, putting populations at risk of new infectious diseases.35 -37
Conclusion
Incorporating geographic determinants into public health strategies will lead to more effective, context-specific interventions, reducing health disparities and promoting better health outcomes for geographically marginalized populations. From the prolonged effects of hypoxia at high altitudes to the unique challenges of water scarcity in desert regions, geography shapes health in ways that must be recognized and addressed. A comprehensive understanding of these determinants, combined with tailored interventions, will contribute to a healthier, more equitable future.
Footnotes
Author Contributions
Conceptualization: EOP; Methodology: EOP, JIC, JVG, Software: JVG, EOP; Validation: JIC, EOP; Investigation: EOP, JIC, JVG, MAM, KCC, MPC; Resources: JVG, MAM, KCC, MPC; Data curation: EOP, JIC; Writing—original draft preparation: JVG, MAM, KCC, MPC; Writing—review and editing: EOP, JIC; Visualization: JIC, JVG, EOP; Supervision: JIC, EOP; Project administration: EOP; Funding acquisition: EOP. All authors have read and agreed to the published version of the manuscript.
Funding
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study did not receive specific grants from funding agencies in the public, commercial, or not-for-profit sectors. However, the authors acknowledge financial support from the Universidad de Las Américas (UDLA), Ecuador, which provided institutional salaries for research staff, stipends for student interns, and covered the article processing charges (APC) associated with this publication.
Declaration of Conflicting Interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.