[Social determinants of the incidence of Covid-19 in Barcelona: a preliminary ecological study using public data.]

Objective: Social determinants and health inequalities have a huge impact on health of populations. It is important to study their role in the management of the Covid-19 epidemic, especially in cities, as certain variables like the number of tests and the access to health system cannot be assumed as equal. The aim of this work was to determine the relation of social determinants in the incidence of Covid-19 in the city of Barcelona.

Methods: An observational retrospective ecological study was performed, with the neighbourhood as the population unit, based on data of cumulative incidence published at May 14th, 2020 by the Public Health Agency of Barcelona. Covid-19 incidence disparities depending on the income of the neighbourhoods, the Pearson linear correlation of the variables selected (age, sex, net density, immigrants, comorbidities, smokers, Body Mass Index [BMI] and Available Income per Family Index [AIFI]) with the incidence and the correlation with a multivariant Generalized Linear Model (GLM) were estimated.

Results: It was found that neighbourhoods belonging to the lowest quintile of income had a 42% more incidence than those belonging to the highest quintile: 942 cases per 100,000 inhabitants versus 545 per 100,000 inhabitants of the highest quintile. The Pearson correlation was statistically significative between the incidence of Covid-19 and the percentage of population over 75 (r=0.487), the percentage of immigration of the neighbourhood and the origin of the immigrants (r=-0.257), the AIFI (r=-0.462), the percentage of smokers (r=0.243) and the percentage of people with BMI over 25 (r=0.483). The GLM showed that the most correlated variables with the incidence are the percentage of people over 75 (Z-score=0.258), the percentage of people from Maghreb (Z-score=-0.206) and Latin America (Z-score=0.19) and the percentage of people with BMI over 25 (Z-score=0.334). The results of the GLM were significative.

Conclusions: Social determinants are correlated with the modification of the incidence of Covid-19 in the neighbourhoods of Barcelona, with special relevance of the prevalence of BMI over 25 and the percentage of immigrants and its origin.