[Impact of extreme temperatures on primary care requirement in France: the CHAUFOS Study (2010-2018).]

The health impact of cold and hot waves is major. Nevertheless, the respective impact of extreme high and low temperatures remains controversial.The daily number of (1)#160;patients managed by SAMU#160;93 dispatching centre#8211; primary care requirement indicator, (2)#160;Mobile Intensive Care Unit (MICU) interventions#8211; patient severity indicator and (3)#160;number of deaths have been recorded. Daily minimum and maximum temperatures were recorded from 2010 to 2018. The analysis covered the 10#160;warmest and coldest days of each year (2#160;#215;#160;70#160;days), and the 30#160;warmest and coldest days of the total period (2#160;#215;#160;30 days).Over 2,702#160;days, 1,513,070#160;patients, 89,478#160;MICU interventions and 7,350#160;deaths were analysed. Median temperature: 16.0[10.4-21.6]#176;C.The coldest days were associated with a significant increase in patients managed (665[609-764] vs 538[474-619]; P#160;lt;#160;0.001), MICU interventions (35[32-39] vs 33 [28-38]; P#160;=#160;0.006) and deaths (3[2-5] vs 2[1-4]; P#160;=#160;0.0008) considering the 10#160;days of extreme temperatures in each year and a significant increase in patients managed 615[580-698] vs 542[475-627]; P#160;lt;#160;0.001) considering the 30-day extreme of the period.The hottest days were associated with a significant decrease in patients managed (484[443-549] vs 538[474-619]; Plt;#160;0.001), MICU interventions (31[25-37] vs 33[28-38]; P#160;=#160;0.006) and deaths (2[1-3] vs 2[1-4]; P#160;=#160;0.0008) considering the 10 extreme days of each year and a significant decrease in patients managed (536[479-576] vs 542[475-627]; Plt;#160;0.001) considering the 30 extreme days of the period.Primary care requirement, number of severe patients and mortality increased significantly with extreme low of temperature.