Post-recovery impact of the second and third SARS-CoV-2 infection waves on healthcare resource utilization in Lombardy, Italy

The administrative claims database of the Italian region Lombardy, the first in Europe to be hit by the SARS-CoV-2 pandemic, was employed to evaluate the impact on healthcare resource utilization following recovery from the second (mainly alpha-related variant) and third (delta-related) infection waves. 317,164 individuals recovered from the infection and became negative after the second wave, 271,180 after the third. Of them, 1571 (0.5%) and 1575 (0.6%) died in the first 6 post-negativization months. In the remaining cases (315,593 after the second wave and 269,605 after the third), hospitalizations, attendances to emergency rooms and outpatient visits were compared with those recorded in the same pre-pandemic time periods in 2019. Dispensation of drugs as well as of imaging, and functional and biochemical diagnostic tests were also compared as additional proxies of the healthcare impact of the SARS-CoV-2 infection waves. Following both waves, hospitalizations, attendances at emergency rooms, and outpatient visits were similar in number and rates to the pre-pandemic periods. However, there was an increased dispensation a number of drugs and diagnostic tests, particularly those addressing the cardiorespiratory and blood systems. In a large region such as Lombardy taken as a relevant model because early and severely hit by the SARS-CoV-2 pandemic, the post-COVID burden on healthcare facilities was mildly relevant in cases who recovered from the second and third infection waves regarding such pivotal events as deaths, hospitalizations, and need for emergency room and outpatient visits, but was high regarding the dispensation of some drug classes and types of diagnostic tests.