Heat-related mortality in Europe during the summer of 2022

Abstract

Over 70,000 excess deaths occurred in Europe during the summer of 2003. The resulting societal awareness led to the design and implementation of adaptation strategies to protect at-risk populations. We aimed to quantify heat-related mortality burden during the summer of 2022, the hottest season on record in Europe. We analyzed the Eurostat mortality database, which includes 45,184,044 counts of death from 823 contiguous regions in 35 European countries, representing the whole population of over 543 million people. We estimated 61,672 (95% confidence interval (CI) = 37,643-86,807) heat-related deaths in Europe between 30 May and 4 September 2022. Italy (18,010 deaths; 95% CI = 13,793-22,225), Spain (11,324; 95% CI = 7,908-14,880) and Germany (8,173; 95% CI = 5,374-11,018) had the highest summer heat-related mortality numbers, while Italy (295 deaths per million, 95% CI = 226-364), Greece (280, 95% CI = 201-355), Spain (237, 95% CI = 166-312) and Portugal (211, 95% CI = 162-255) had the highest heat-related mortality rates. Relative to population, we estimated 56% more heat-related deaths in women than men, with higher rates in men aged 0-64 (+41%) and 65-79 (+14%) years, and in women aged 80+ years (+27%). Our results call for a reevaluation and strengthening of existing heat surveillance platforms, prevention plans and long-term adaptation strategies.

Fig. 1. Temperature-related risk of death during 2015–2019.

a,b, Cumulative relative risk of death (unitless) in Europe for the overall population (black), women (red) and men (blue) (a) and people aged 0–64 (blue), 65–79 (red) and 80+ (black) years (b), together with their 95% CIs (shadings). c–f, Regional relative risk of death (unitless) at the temperature 95th centile for the overall population (c), people aged 80+ years (d), women (e) and men (f).

Fig. 2. Weekly temperature and heat-related mortality numbers in Europe during the summer of 2022.

a, Weekly baseline (gray line) and observed (black line) temperature (°C) averaged over Europe. Temperature anomalies are defined as the difference between observed and baseline temperatures (gray shading). Baseline temperatures were computed as the mean annual cycle of observed temperatures in the reference period 1991–2020. b,c, Weekly heat-related mortality (weekly deaths) aggregated over Europe for the overall population (black), women (red) and men (blue) (b) and people aged 0–64 (blue), 65–79 (red) and 80+ (black) years (c), together with their 95% CIs (shadings). The numbers for women and men in b do not include the United Kingdom; values for the age groups in c do not include Germany, Ireland and the United Kingdom.

Fig. 3. Regional temperature anomaly and heat-related mortality rate during the summer of 2022.

a, Regional temperature anomaly (°C) averaged over the summer. b–f, Regional heat-related mortality rate (summer deaths per million) aggregated over the summer for the whole population (b), women aged 65–79 years (c), men aged 65–79 years (d), women aged 80+ years (e) and men aged 80+ years (f). Summer refers to the 14-week period between 30 May and 4 September 2022 (weeks 22–35).

Fig. 4. The summer of 2022 within the context of rising temperatures in Europe.

a, Year-to-year time series of summer mean temperatures (°C) averaged over the analyzed European countries. The straight lines depict the linear fitting for the 1991–2012 (excluding the year 2003) and 2013–2022 periods. b, Relationship between summer mean temperature (°C) and summer heat-related mortality (summer deaths) in the analyzed European countries. The straight line shows the linear fitting for the 2015–2022 period.

Extended Data Fig. 1. European sex- and age-specific temperature-related risk of death and heat-related mortality.

Panels (a-d) depict the cumulative relative risk of death (unitless) in Europe during 2015-2019. Panels (e-h) display the weekly heat-related mortality (weekly deaths) aggregated over Europe during the summer of 2022. The shadings represent the 95% confidence intervals. All-age data by sex was not available in the United Kingdom (red and blue lines in panels a,e). Data by sex and age groups was not available in the United Kingdom, Ireland and Germany (panels b-d, f-h).

Extended Data Fig. 2. Regional temperature anomaly and heat-related mortality rate during weeks 22, 23 and 24.

Regional temperature anomaly (a,c,e; °C) and heat-related mortality rate (b,d,f; weekly deaths per million) during weeks 22 (May 30 – June 5; a,b), 23 (June 6 – June 12; c,d) and 24 (June 13 – June 19; e,f) of the year 2022.

Extended Data Fig. 3. Regional temperature anomaly and heat-related mortality rate during weeks 25, 26 and 27.

Regional temperature anomaly (a,c,e; °C) and heat-related mortality rate (b,d,f; weekly deaths per million) during weeks 25 (June 20 – June 26; a,b), 26 (June 27 – July 3; c,d) and 27 (July 4 – July 10; e,f) of the year 2022.

Extended Data Fig. 4. Regional temperature anomaly and heat-related mortality rate during weeks 28, 29 and 30.

Regional temperature anomaly (a,c,e; °C) and heat-related mortality rate (b,d,f; weekly deaths per million) during weeks 28 (July 11 – July 17; a,b), 29 (July 18 – July 24; c,d) and 30 (July 25 – July 31; e,f) of the year 2022.

Extended Data Fig. 5. Regional temperature anomaly and heat-related mortality rate during weeks 31, 32 and 33.

Regional temperature anomaly (a,c,e; °C) and heat-related mortality rate (b,d,f; weekly deaths per million) during weeks 31 (August 1 – August 7; a,b), 32 (August 8 – August 14; c,d) and 33 (August 15 – August 21; e,f) of the year 2022.

Extended Data Fig. 6. Regional temperature anomaly and heat-related mortality rate during weeks 34 and 35.

Regional temperature anomaly (a,c; °C) and heat-related mortality rate (b,d; weekly deaths per million) during weeks 34 (August 22 – August 28; a,b) and 35 (August 29 – September 4; c,d) of the year 2022.

Extended Data Fig. 7. Sensitivity to the period of calibration of the epidemiological associations.

Panels (a,b) depict the cumulative relative risk of death (unitless) in Europe (a) and the weekly heat-related mortality (weekly deaths) aggregated over Europe during the summer of 2022 (b), together with their 95% confidence intervals (shadings). Panels (c-f) display the regional relative risk of death (unitless) at temperature 95^th percentile (c,d) and the regional heat-related mortality rate (summer deaths per million) aggregated over the summer of 2022 (e,f). Values were obtained from epidemiological models calibrated with data from the periods 2015-2019 (black in a,b; and maps in c,e) and 2015-2022 (red in a,b; and maps in d,f). Summer refers to the 14-week period between May 30^th and September 4^th of 2022 (weeks 22-35).

Extended Data Fig. 8. Meta-predictors included in the meta-regression.

Maps correspond to the regional temperature average (a, °C), temperature inter-quartile range (b, °C) and percentage of people aged 80+ years (c, %).