Area-level indicators of income and total mortality during the COVID-19 pandemic

Background There is mounting evidence that socioeconomic inequalities in mortality have widened during the COVID-19 pandemic. This study aimed at evaluating the relationship between area-level indicators of income and total mortality during the first phase of COVID-19 pandemic in the most hit Italian region. Methods We conducted an ecological study based on the number of deaths registered in the municipalities of the Lombardy region (Italy) between January 2019 and June 2020. Municipalities were grouped according to quintiles of average income and pension of their resident population. Monthly age-standardized mortality ratios (MRs) between the poorest and the richest municipalities and the corresponding 95% CI were computed to evaluate whether the pre-existing socioeconomic inequalities widened during the pandemic. Results Over the study period, 175 853 deaths were registered. During the pre-pandemic period (January 2019 to February 2020) the MR between the poorest and the richest municipalities ranged between 1.12 (95% CI: 1.00–1.25) and 1.33 (95% CI: 1.20–1.47). In March 2020, when the pandemic began to rapidly spread in the region, it raised up to 1.61 (95% CI: 1.51–1.72) and decreased thereafter, reaching the pre-pandemic values in April 2020. Similar results were observed in the analysis of the mortality at ages 65 and over in municipalities grouped according to average pension, where the MR increased up to 1.82 (95% CI: 1.70–1.94) in March 2020. Conclusions The socioeconomic inequalities in mortality widened in Lombardy, the Italian region most severely hit during the first phase of the COVID-19 pandemic.