Regional variations in Italy's COVID-19 death toll: a descriptive analysis of excess mortality and associated factors from 2020 to 2021.

Background: Italy implemented various measures, including lockdowns and a mass vaccination campaign, to address the COVID-19 pandemic. This study aims to describe the temporal and regional differences in mortality trends between March 2020 and December 2021, along with associated socioeconomic, policy, and behavioral factors.

Methods: We used National Ministry of Health data on COVID-19 mortality, excess mortality (EM), and vaccine uptake, along with data from the Italian arm of a European survey of preventive behaviors and attitudes, such as trust in institutions. The analysis was conducted across four macro regions and five study periods. Avertable mortality was calculated as observed EM minus the lowest EM at the macro-regional level for each study period.

Results: In 2020-21, the estimated total EM was 180,169 deaths, with 76.4% officially attributed to COVID-19. This proportion ranged from 13.5% in the South and Islands (June-October 2020) to 140.0% in the Northeast (March-July 2021). Excess and avertable mortality peaked in the North during the first two periods (March 2020 - February 2021) and in the South and Islands thereafter (March-December 2021). Survey data revealed reduced adherence to stay-at-home orders in the North and lower trust in hospitals and reduced vaccine uptake, especially among the elderly, in the South and Islands. After the initial period, 33,587 deaths (18.6%) could have been averted if each macro-region had matched the lowest rates observed in that period. An estimated 40.7% of avertable deaths occurred in Southern and Insular Italy, which constitutes 33.7% of the national population.

Conclusions: Due to differential misreporting, EM estimates offer a more accurate view of regional and temporal patterns in COVID-19 mortality than official rates. The higher EM in northern Italy during the first year of the pandemic might be linked to lesser adherence to control policies, possibly associated with higher private-sector employment. The higher EM in the South and Islands post-March 2021, contributing to 40.7% of avertable EM, could be partly explained by the lower vaccination rates in the population aged 80 and older, who experienced the highest age-specific mortality rates and lower trust in the healthcare system in this macro-region.