Health outcomes of COVID-19 in immigrants versus native Spaniards.

Background: During the SARS-CoV-2 pandemic, the differential impact on ethnic groups has been widely debated. This study examines the immigrant population of Fuenlabrada, Spain, analyzing their infection, hospitalization, ICU admission, and mortality rates compared with the Spanish population. Methods: This ambispective observational study (March 2020-January 2023) analyzed infection rates, hospitalizations, ICU admissions, and deaths among 215,000 inhabitants (10 % immigrants). Propensity score analysis was conducted to ensure comparability between groups. Findings: Among 14,688 patients with 18,724 infections, 4102 (21·9 %) infections occurred in immigrants. Of 5429 hospitalized infections, 989 (19·2 %) involved immigrants. Immigrants had more than double the hospitalization rates of Spaniards (fourfold among Latin Americans). Spaniards were older (by 16 years), had higher comorbidities, longer hospital stays, and higher one-month mortality (4·9 % vs. 1 %). Vaccination rates were lower among immigrants (Spaniards 77 %, Latin Americans 70 %, other immigrants ∼50 %). Adjusted analyses revealed no significant differences in mortality between groups. Interpretation: Elevated infection rates in immigrants, particularly Latin Americans, likely explain their higher hospitalization and ICU admission rates. Mortality, adjusted for demographics and clinical factors, did not differ significantly. Future research should explore the socio-demographic and genetic contributors to these disparities.