Excess Seasonal Mortality

Healthy People
Mortality
Deaths
Avoidable Mortality
Winter Mortality
Vulnerable Populations
Heatwave Preparedness
Air Pollution
Cold Weather
Housing Weatherisation
Seasonal Immunisation
Emergency Response
Asthma
Excess Seasonal Mortality

introduction Introduction

Excess seasonal mortality occurs where there is a higher rate of death in one part of the year than the average for the rest of the year. People are more likely to die in conditions of extremes in temperature.  In the UK this is usually in the winter and the most commonly used measure is the (Excess) Winter Mortality Index.

Excess deaths have been reported in the summer in recent years but these are generally an excess compared to what happened in the same period in previous years, rather than a comparison between seasons.

Excess deaths from exposure to extremes of heat or cold increased by around 2% per 1°C temperature change. In addition, whilst the effects of extremes of heat were normally evident rapidly, within 24 hours, exposure to extremes of cold could take as long as 4 weeks to manifest itself in premature death1.

There are also excess deaths that result from extreme weather events, either from freezing conditions (snow and ice causing falls, fractures and road traffic accidents) or from excess heat (heat waves causing overheating in the elderly or vulnerable, causing exhaustion, dehydration and confusion).

The Winter Mortality Index compares the number of death occurrences in the winter period (December to March) with the average number of death occurrences in the preceding August to November and the following April to July (non winter period). The calculation used is:

\[ \text{Winter Deaths Compared to Non-Winter Deaths} = \text{Winter Deaths} - \text{Average Non-Winter Deaths} \]

The Index itself is expressed as a percentage and is calculated so comparisons can be made between groups:

\[ WMI = \left( \frac{\text{Winter Deaths Compared to Non-Winter Deaths}}{\text{Average Non-Winter Deaths}} \right) \times 100 \]

A negative WMI means there were higher deaths in the non winter periods than the winter period.

why is it important to population health Why is it important to Population Health?

Reducing excess seasonal mortality contributes to the overarching goal of increasing life expectancy and healthy life expectancy. Not only is the aim to increase both indicators, but to reduce the gap between them and to reduce inequalities.

Winter mortality is not solely a reflection of temperature, but of other factors as well. These include respiratory diseases and pressure on services, which have been more intense than usual during and following the height of the COVID 19 pandemic 2.

Excess seasonal mortality has the greatest impact on those on low incomes, those living alone, the elderly, vulnerable, disabled and those living in care homes but also the young living in cold and damp housing.

the derbyshire population approach The Derbyshire Population Health Approach

The Derbyshire Population Health Approach focuses on prevention, population health, evidence-informed practices, causes, and collaboration. It emphasises proactive measures to prevent health issues, tailors interventions to specific populations, incorporates evidence-informed practices, addresses underlying causes, and promotes collaboration for effective action.

When considering the topic of excess seasonal mortality within The Derbyshire Population Health Approach:

• Prevention Prevention

Prevention strategies for seasonal excess deaths focus on minimising the impact of extreme temperatures on vulnerable Derbyshire populations during both winter and summer seasons. This includes efforts to prevent exposure to extreme cold and extreme heat through initiatives such as weatherisation programs for homes, provision of heating and cooling assistance, and public awareness campaigns on weather-related risks. Prevention also involves addressing the underlying causes of vulnerability, such as inadequate housing, lack of access to healthcare, and socioeconomic disparities.

• Population Population

A population-focused approach recognises that certain groups, including the elderly, children, individuals with chronic illnesses, and those with limited access to resources, are more vulnerable to seasonal excess deaths. Understanding Derbyshire’s demographics and geographic areas most at risk is essential for targeting interventions effectively. Tailoring strategies to protect vulnerable populations during extreme weather events is a key aspect of this approach including promotion of immunisation to protect older people, young children and those with long term conditions against seasonal flu and other diseases.

• Evidence Evidence

The Population Health Approach to seasonal excess deaths relies on evidence-based practices and research to guide interventions and policies. This includes monitoring seasonal excess mortality rates, studying the health impacts of extreme temperatures, and assessing the effectiveness of interventions. Evidence-based approaches help identify the most vulnerable populations, evaluate the success of preventive measures, and adapt strategies in response to changing climate patterns.

• Causes Causes

Understanding the root causes of seasonal excess deaths involves examining the factors that contribute to vulnerability during extreme temperatures. This includes socioeconomic factors, housing conditions, access to healthcare, and behavioural practices. Population health initiatives aim to address these underlying causes through policies, social support programs, improved urban planning, and educational campaigns that raise awareness about the risks associated with extreme temperatures.

• Collaboration Collaboration

Collaboration among various Derbyshire stakeholders is vital for preventing seasonal excess deaths and responding effectively to climate-related challenges. Stakeholders may include government agencies, healthcare providers, community organisations, emergency responders, and environmental experts. Collaborative efforts can lead to the development of comprehensive heat and cold action plans, early warning systems, and population health campaigns that promote adaptive behaviours during extreme weather events. In Derbyshire voluntary, community and charity organisations can apply for a grant from Derbyshire County Council to open a Warm and Welcoming Space this winter.

latest derbyshire data Latest Derbyshire Data

Trend Data

Prevalence Maps of Derbyshire

The maps below illustrate various geographies for Derbyshire. LSOAs and MSOAs are geographical divisions used for statistical purposes, allowing for more detailed analysis of local data. In these maps, you can explore various health indicators and data for Derbyshire, providing valuable insights into the area’s health and wellbeing.

In the top right of the map, you’ll find the ‘Layer Control’ icon. This is an easy way to customise what you see on the map visualisation. Click the ‘Layer Control’ to choose which information is displayed on the map. Pick the indicator that interests you the most, and the map will transform accordingly.

Slope Index

This chart illustrates the differences in health and lifestyle factors across areas in Derbyshire, from the most deprived (decile 1, red) to the least deprived (decile 10, green). As you move from left to right on the chart (from more deprived to less deprived areas), the line shows whether these factors are becoming more or less common. Essentially, it’s a way to see how living in wealthier or poorer areas affects the prevalence of these factors.

further analysis and assessments Further Analysis & Assessments

Derbyshire Joint Strategic Needs Assessment (JSNA) involves a thorough examination of a specific health problem, exploring its causes, consequences, and underlying factors. It combines various data sources, collaboration with stakeholders, and rigorous analysis to generate insights for evidence-informed interventions and policy changes.

more information and resources More Information & Resources

Here are some useful resources and information to help prevent issues related to excess seasonal mortality. These materials are meant to provide individuals, healthcare professionals, and communities with the knowledge and tools they need as part of efforts to address this issue.

Contributors

Chris McManus, Advanced Public Health Practitioner (Epidemiology), Knowledge and Intelligence Team