Residency · Residency · Medicine Pediatrics
Climate Change and Health Across the Lifespan
Introduction
Climate change is a health emergency with profound implications across the lifespan. Children, pregnant women, older adults, and those with chronic diseases are disproportionately vulnerable. Rising temperatures, extreme weather events, air pollution, vector-borne disease expansion, and food insecurity are already causing measurable health effects worldwide. Med-peds physicians must understand the mechanisms through which climate change affects human health, recognize climate-sensitive conditions, and advocate for mitigation and adaptation strategies.
Climate Change and Human Health: Pathways
Direct Effects
Extreme heat: Heat exhaustion, heat stroke, exacerbation of cardiovascular and renal disease. Extreme weather events: Hurricanes, floods, and wildfires cause injuries, displacement, and mental health trauma. Wildfires: Particulate matter (PM2.5) exposure causes acute respiratory exacerbations and long-term cardiovascular risk. Drought: Water scarcity affecting hygiene, agriculture, and nutrition.
Indirect Effects
Air quality degradation: Ground-level ozone and PM2.5 from fossil fuel combustion worsen asthma, COPD, and cardiovascular disease. Allergen changes: Longer pollen seasons and higher pollen counts increase allergic disease burden. Vector-borne disease expansion: Warming temperatures expand geographic range of mosquitoes (dengue, Zika, malaria) and ticks (Lyme disease) Food insecurity: Crop failures, fishery decline, and nutritional quality reduction from elevated CO2. Water-borne disease: Flooding increases contamination; warming favors Vibrio and harmful algal blooms. Mental health: Eco-anxiety, climate grief, PTSD from extreme events, and displacement.
Vulnerable Populations Across the Age Spectrum
| Population | Key Vulnerabilities | Primary Climate Threats | Clinical Considerations |
|---|---|---|---|
| Children | Immature thermoregulation; developing organs; high metabolic rate | Heat illness, asthma from air pollution, vector-borne disease | Sports safety protocols; asthma action plans with AQI triggers |
| Pregnant women | Altered thermoregulation; fetal vulnerability | Preterm birth, preeclampsia, stillbirth | Heat avoidance counseling; air quality monitoring |
| Older adults | Impaired thermoregulation; polypharmacy; social isolation | Heat stroke, cardiovascular events, respiratory exacerbations | Medication review (diuretics, anticholinergics); welfare checks |
| Chronic disease | Impaired adaptive capacity | Disease exacerbation, medication instability | Insulin storage plans; inhaler action plans; hydration counseling |
Children
Children are disproportionately vulnerable due to higher metabolic rates, immature organ systems, behavioral patterns, and longer time horizon for cumulative exposures. Heat-related illness: Children thermoregulate less efficiently; sports-related heat illness is increasing. Asthma exacerbations: Air pollution and allergen increases drive emergency visits; asthma is already the leading cause of pediatric chronic disease. Infectious disease: Diarrheal diseases increase with flooding and water contamination; vector-borne diseases expand into new regions. Malnutrition: Climate-driven food insecurity affects growth and neurodevelopment. Mental health: Children and adolescents experience eco-anxiety, climate grief, and trauma from displacement. Developmental effects: Prenatal air pollution exposure is associated with low birth weight, preterm birth, and neurodevelopmental disorders.
Pregnant Women
Heat exposure increases risk of preterm birth, low birth weight, and stillbirth. Air pollution (PM2.5, ozone) is associated with gestational hypertension and preeclampsia. Climate-driven food insecurity affects maternal nutrition and fetal growth. Infectious disease expansion (Zika virus) poses teratogenic risks.
Older Adults
Heat vulnerability: Impaired thermoregulation, chronic disease burden, polypharmacy (diuretics, anticholinergics reduce heat adaptation) Social isolation amplifies heat risk; the 2003 European heat wave killed an estimated 70,000, predominantly elderly. Cardiovascular and respiratory exacerbations from air pollution and extreme temperatures. Displacement from extreme weather events is particularly disruptive for older adults with mobility limitations and care needs.
Chronic Disease Populations
Asthma and COPD: Worsened by air pollution, allergens, and wildfire smoke. Cardiovascular disease: Heat stress increases cardiac workload; PM2.5 is an independent cardiovascular risk factor. Diabetes: Heat impairs insulin storage and glucose regulation; food insecurity disrupts dietary management. Kidney disease: Dehydration and heat stress exacerbate CKD; "Mesoamerican nephropathy" linked to occupational heat exposure. Mental illness: Lithium toxicity risk increases with dehydration; heat-related psychiatric emergencies increase during heat waves.
Clinical Implications
Heat-Related Illness
Heat exhaustion: Core temperature 37-40 degrees C; fatigue, headache, nausea, diaphoresis; treat with cooling and hydration. Heat stroke: Core temperature >40 degrees C with altered mental status; medical emergency requiring aggressive cooling (cold water immersion, evaporative cooling) Pediatric dosing for IV rehydration; adult management includes ICU-level monitoring for organ dysfunction. Prevention: Hydration, acclimatization, avoiding exertion during peak heat, checking on elderly during heat waves.
Air Quality and Respiratory Health
Monitor Air Quality Index (AQI) and advise patients to limit outdoor activity when AQI >100. Asthma action plans should incorporate air quality triggers. N95 masks provide protection from wildfire smoke particulate matter. Long-term PM2.5 exposure is associated with reduced lung development in children and accelerated lung function decline in adults.
Vector-Borne Disease Surveillance
Expanding ranges of Aedes aegypti and Aedes albopictus mosquitoes bring dengue, Zika, and chikungunya to previously unaffected regions. Tick-borne diseases: Lyme disease expanding northward and to higher altitudes; longer tick seasons. Clinicians in newly affected areas must maintain awareness and diagnostic capability.
Physician Advocacy and Healthcare Sustainability
The healthcare sector contributes 4.4% of global greenhouse gas emissions; hospitals and health systems have a responsibility to reduce their carbon footprint. Prescribing practices: Metered-dose inhalers have a significantly higher carbon footprint than dry powder inhalers; consider when clinically equivalent. Telemedicine: Reduces patient travel and associated emissions. Sustainable hospital practices: Energy efficiency, waste reduction, local food sourcing. Physician advocacy for clean energy policy, air quality standards, and climate adaptation infrastructure. Medical education should integrate climate and health curriculum.
Clinical Pearls
Children are the most vulnerable population to climate change health effects due to physiologic, developmental, and exposure factors. Heat stroke is a medical emergency; rapid cooling to below 39 degrees C within 30 minutes improves survival. Air pollution is a leading environmental risk factor for disease globally; anticipatory guidance on AQI monitoring should be routine. Vector-borne disease geographic ranges are expanding; clinicians must maintain awareness of emerging local risks. Physicians have a professional obligation to advocate for climate policies that protect health and reduce healthcare's carbon footprint.
References
- Watts N, Amann M, Arnell N, et al. The 2020 report of The Lancet Countdown on health and climate change. Lancet. 2021;397(10269):129-170.
- Perera FP. Multiple threats to child health from fossil fuel combustion: Impacts of air pollution and climate change. Environ Health Perspect. 2017;125(2):141-148.
- Salas RN, Shultz JM, Solomon CG. The climate crisis and clinical practice. N Engl J Med. 2020;382(7):589-591.
- Ebi KL, Capon A, Berry P, et al. Hot weather and heat extremes: Health risks. Lancet. 2021;398(10301):698-708.