Does Cold Affect Health More Than Heat? What a Study in Russia Reveals

Not only heatwaves in southern Europe pose a health risk. What about cold countries like Russia? A new study reveals it.

Can temperatures in places like Russia still pose serious risks to people’s health? Until recently, most of the evidence about temperature-related mortality in Russia was limited to a few studies based on short time periods or single cities. This left a significant knowledge gap for a country where winters are long and harsh, and summers are short—but becoming increasingly hotter due to climate change.

Through the EARLY-ADAPT project, we analysed over 19 million deaths across 300 Russian cities from 2000 to 2019, covering a wide range of climate zones and socio-economic conditions. We aimed to understand how both cold and heat exposure influences mortality in one of the world’s coldest and most geographically diverse nations.

Heat- and cold-related temperature risks vary unevenly across country

We found that temperature-related health risks differ significantly between cities.

• While heat-related mortality was higher in the European part of Russia, cold-related risks were more evenly distributed across regions.
• Cities with milder winters and hot summers had higher vulnerability to heat, while cities with more continental climates still showed considerable cold-related mortality.
• Cold-related risk did not follow a clear geographic gradient—possibly due to higher levels of infrastructure adaptation across the country.
• In contrast, heat-related risk showed a strong spatial pattern, with southern and western cities being the most affected.

This means that public health strategies cannot be performed as a universal solution – they need to be adapted to the specific regional climate patterns in the country.

Yatutsk. Photo: Alina Makhatyrova / Unsplash. 

Who is most at risk? Age and sex gap

We also looked closely at how temperature-related mortality varies by age and sex.

• Unsurprisingly, older adults—especially those aged 75 and above—were much more vulnerable to both heat and cold.
• But there were also some interesting disparities between men and women. There was notable gap between men and women: the differences in heat-related mortality risk were more pronounced among women than among men. However, among middle-aged men, the risk of heat-related mortality was higher compared to women of the same age group.

These sex- and age-specific patterns have also been observed in European studies, but in Russia, some Siberian cities showed opposite trends: higher heat-related mortality for men in the 0–59 years age group, and higher cold-related mortality in those aged 60–74. These unusual regional patterns might be explained by comorbidities, work-related exposure, or behavioral factors.

Temperature impact: the numbers behind the risk

How much do temperatures contribute to mortality in Russia? We calculated both the attributable number (how many deaths are linked to temperature) and attributable fraction (what percentage of total deaths are due to temperature).

Overall, around 11% of all deaths were linked to non-optimal temperatures, with most of these related to cold. Importantly, even in a country where people are used to harsh winter conditions, cold exposure accounted for 10.47% of all deaths, while heat was responsible for 0.67%. That translates to 99,631 annual deaths from cold and 6,376 from heat.

While cold is still the dominant contributor to mortality in Russia, heatwaves also represent a growing threat, particularly in regions less prepared for them

The difference between cold and heat-related attributable fraction is less when we consider extreme temperatures: 0.65% and 0.40% respectively. This shows that while cold is still the dominant contributor to mortality in Russia, heatwaves also represent a growing threat, particularly in regions less prepared for them.

Moscow. Photo: Aleksandr Popov / Unsplash. 

Regionally specified adaptation plans

One of the study’s key takeaways is the need for geographically targeted health policies. Because the temperature risks vary so much by region—and because age and sex also affect vulnerability—it’s not enough to have a national strategy. Instead, local governments and health systems should create custom adaptation plans based on their specific climate and population. For example, a city in Siberia might need to focus more on the primary causes of high temperature-related risks among middle-age male population, while a city in the south should prepare for heatwaves that threaten the most vulnerable elderly population.

One of the study’s key takeaways is the need for geographically targeted health policies. Because the temperature risks vary so much by region—and because age and sex also affect vulnerability—it’s not enough to have a national strategy.

This kind of accuracy planning is essential for reducing avoidable deaths and preparing for the ongoing effects of climate change. As the climate continues to change, these insights will be crucial for shaping effective, life-saving public health strategies. Even familiar climates can still be deadly—especially for society’s most vulnerable.