LAUSR

Objective To explore the link between COVID-19 incidence, socio-economic covariates, and NHL incidence. Design Ecological study design. Setting Sardinia, Italy. Participants We used official reports on the total cases of COVID-19 in 2020, published data on NHL incidence, and socio-economic indicators by administrative unit, covering the whole regional population. Main outcomes and measures We used multivariable regression analysis to explore the association between the natural logarithm (ln) of the 2020 cumulative incidence of COVID-19 and the ln-transformed NHL incidence in 1974-2003, weighing by population size and adjusting by socioeconomic deprivation and other covariates. Results The cumulative incidence of COVID-19 increased in relation to past incidence of NHL (p < 0.001), socioeconomic deprivation (p = 0.006), and proportion of elderly residents (p < 0.001) and decreased with urban residency (p = 0.001). Several sensitivity analyses confirmed the finding of an association between COVID-19 and NHL. Conclusion This ecological study found an ecological association between NHL and COVID-19. If further investigation would confirm our findings, shared susceptibility factors should be investigated among the plausible underlying mechanisms.