Healthcare system overstretch and in-hospital mortality of intubated COVID-19 patients in Greece: an updated analysis, September 2020 to April 2022

BackgroundOur previous analysis showed how in-hospital mortality of intubated COVID-19 patients in Greece is adversely affected by patient load and regional disparities. We aimed to update this analysis to include the large "delta" and "omicron" waves that affected Greece during 2021-2022, while also considering the effect of vaccination. MethodsAnonymized surveillance data were analyzed from all COVID-19 patients in Greece intubated between 1 September 2020 and 4 April 2022, and followed up until 17 May 2022. Poisson regression was used to estimate the hazard of dying as a function of fixed and time-varying covariates. ResultsMortality was significantly higher above 400 patients, with an adjusted Hazard Ratio of 1.22, 95% CI: 1.09-1.38), rising progressively up to 1.48 (95% CI: 1.31-1.69) for 800+ patients. Hospitalization away from Attica region was also independently associated with increased mortality, as was hospitalization after 1 September 2021 (HR=1.21, 95% CI: 1.09-1.36). Vaccination did not affect the mortality of these already severely ill patients. ConclusionOur results confirm that in-hospital mortality of severely ill COVID-19 patients is adversely affected by high patient load and regional disparities, and point to a further significant deterioration after 1 September especially away from Attica and Thessaloniki. This highlights the need for urgent strengthening of healthcare services in Greece, ensuring equitable and high-quality care for all.