New analysis from the Government Actuary’s Department and international researchers highlights how extreme heat, ageing populations and climate pressures could increasingly affect mortality, NHS demand and public services.
As temperatures rise and populations age, climate change is increasingly becoming a health and public services challenge as much as an environmental one.
New work presented by the Government Actuary’s Department (GAD), alongside international research examining mortality across more than 550 European regions, is drawing attention to the complex relationship between extreme weather, ageing and health.
At an international webinar on climate change, ageing and health, experts brought together evidence from the UK, Europe, Africa and Bangladesh to examine how rising temperatures and environmental disruption could affect mortality, healthcare systems and older populations.
The discussion comes as the UK experiences another period of extreme summer temperatures, increasing scrutiny of whether the NHS and wider public services are sufficiently prepared for climate-related health pressures.
Climate Change as a ‘Compounding Risk’
Rather than looking solely at deaths directly attributed to heatwaves, the Government Actuary’s Department is examining climate change as a “compounding risk”.
Georgina Bedenham, Head of Climate and Disaster Risk at GAD, outlined work to develop a systems map showing how climate hazards could ultimately influence mortality in the UK.
The model considers direct pressures including extreme heat, flooding, deteriorating air quality, vector-borne disease and food and water safety.
But it also examines less obvious pathways through which climate change could affect health, including infrastructure strain, economic disruption, supply-chain pressures and population displacement.
The significance of the approach is that climate-related mortality may not always follow a simple pathway from extreme weather to ill health.
Flooding, for example, can damage homes and healthcare infrastructure, interrupt transport, prevent people from accessing services and cause longer-term financial and mental health consequences.
Similarly, wider economic disruption can affect employment, incomes, housing and ultimately the resources available for healthcare and other public services.
GAD is now expected to finalise and publish its systems map, while considering its implications for actuarial analysis and the measures that could improve resilience..
Extreme Heat and Mortality Across Europe
Alongside the UK work, Professor Torsten Kleinow, Director of the Research Centre for Longevity Risk at the University of Amsterdam, presented research examining the relationship between environmental conditions and short-term mortality across Europe.
The analysis covers more than 550 regions across 20 European countries, comparing weekly mortality against region-specific seasonal expectations.
Among the environmental factors studied, temperature-related variables emerged as the strongest predictors of short-term mortality variation.
Weeks containing several unusually hot days were associated with particularly pronounced increases in mortality, with significant geographical differences across Europe.
Researchers also modelled increasingly severe temperature anomalies, including scenarios in which average daily minimum and maximum temperatures were approximately 12°C above normal.
The findings raise an important issue for health planning: national averages can disguise substantial local differences in vulnerability.
An ageing population, housing quality, deprivation, existing health conditions, local infrastructure and access to healthcare can all influence the consequences of the same extreme weather event.
Why an Ageing Population Changes the Equation
Older people can be particularly vulnerable to extreme heat and climate-related disruption, but the international discussion also challenged the idea that age alone determines vulnerability.
Someone with good health, appropriate housing, transport and strong social networks may be considerably more resilient than another person of the same age living alone, experiencing poor health or struggling to access services.
This means climate-health planning increasingly needs to consider the interaction between age, health, deprivation, housing, geography, infrastructure and social isolation.
Research presented by Professor Liat Ayalon of Bar-Ilan University demonstrated how those pressures can interact.
Her research into the experiences of older people in Togo found communities facing increasingly unpredictable rainfall, severe heat, flooding, deteriorating agricultural conditions and food insecurity.
Approximately 46.6 per cent of participants rated their physical health as poor, while 45 per cent described their mental health as fair or poor.
The research also highlighted an often overlooked consequence of climate-related migration.
Moving away from an environmentally vulnerable area did not necessarily remove vulnerability. Older people could instead lose established family relationships, community networks and informal care arrangements while continuing to experience food and economic insecurity.
Climate resilience, the discussion suggested, is therefore not simply about physical infrastructure. Social networks and community support can themselves act as important forms of resilience.
From Winter Pressures to Summer Pressures?
For the UK, the findings raise questions about how the NHS prepares for increasingly extreme summers.
Health services have traditionally focused significant planning and resources on winter pressures, when respiratory illness, seasonal disease and cold weather increase demand.
But more frequent periods of extreme heat could create a parallel challenge.
Heat can exacerbate cardiovascular and respiratory conditions, increase dehydration and place additional pressure on people already living with complex health conditions.
Climate events can simultaneously affect the infrastructure upon which healthcare depends, from transport and buildings to energy and supply chains.
That creates the potential for increased demand to occur at precisely the moment that parts of the health system are themselves experiencing disruption.
The challenge is therefore broader than simply responding to individual heatwaves.
A New Prevention Challenge for Government
The Government Actuary’s Department’s systems approach also raises a wider question about how government assesses preventative investment.
If climate change affects health through housing, infrastructure, transport, economic security and community resilience, spending in one area could potentially reduce costs elsewhere.
Better housing may reduce heat-related health risks. More resilient infrastructure could maintain access to healthcare during extreme weather. Stronger community networks could help identify vulnerable residents before they require emergency intervention.
The benefits of climate adaptation could consequently be spread across the NHS, social care, local government and the wider economy rather than sitting neatly within the budget of the department making the initial investment.
That creates a challenge for conventional departmental spending decisions, but also an opportunity to consider climate resilience through a longer-term prevention and public-service productivity lens.
Preparing for a Hotter, Older Britain
The UK’s demographic and environmental trajectories are increasingly converging.
The population is ageing while periods of extreme heat are expected to become more frequent and intense. At the same time, the NHS and social care system are already managing rising demand from people living longer with multiple conditions.
The emerging evidence suggests climate resilience will therefore need to become a more prominent part of health and care planning.
The question for policymakers is no longer simply how the UK responds to individual episodes of extreme weather.
It is how the NHS, local government, housing, infrastructure and wider public services are redesigned for a country that is likely to be both hotter and older in the decades ahead.