# The role of social determinants in COVID-19 hospitalization disparities by migration status in Stockholm, Sweden. A population-based cohort study

## TL;DR

This study finds that social and health factors only partly explain why immigrants in Sweden had higher risks of being hospitalized with COVID-19 compared to Swedish-born people.

## Contribution

The study quantifies how much social and health factors contribute to hospitalization disparities among immigrant groups in Sweden.

## Key findings

- Immigrants from Africa and the Middle East had higher hospitalization risks compared to Swedish-born individuals.
- Social and health factors explained only a small portion of the disparities for the most affected immigrant groups.
- Occupation type and residential area were significant contributors to the disparities.

## Abstract

Immigrants in Sweden, particularly those from low- and middle-income countries, had higher risks of COVID-19 mortality and morbidity compared to the Swedish-born. However, prior studies have not quantified the contribution of the differential distribution of health and social determinants to the increased risks.

We used total population registers from Sweden to investigate disparities in COVID-19 hospitalization between five groups of immigrants and Swedish-born, using a cohort 577911 working-age adults (18–65 years) living in Stockholm during the first two waves of the COVID-19 pandemic. Applying a decomposition analysis, we quantified the relative contribution of age, sex, income, education, occupation type, residential area, and pre-existing medical conditions to these disparities.

Our study shows that immigrants have higher risks of hospitalization compared to Swedish-born, and that the investigated factors accounted for these disparities to varying degrees across immigrant groups. For the most affected immigrant groups (from Africa and Middle East), the examined factors together account for only a minor part of the disparities (21% and 18% for Wave 1; 16% and 11% for Wave 2), with occupation type and residential area contributing substantially.

Common observable social determinants of health account for a moderate share of the overall disparities in COVID-19 hospitalizations between Swedish-born individuals and immigrant from the most affected regions of origin.

The COVID-19 pandemic has disproportionately affected foreign-born individuals, who have experienced higher COVID-19–related mortality and morbidity compared to the majority populations in the receiving countries. Using mathematical analysis, we estimated how much of the difference in COVID-19 hospitalization risk between immigrants and the majority population in Sweden can be explained by various factors associated with adverse COVID-19 outcomes, including age, sex, health, and social factors. Our results show that the studied factors account for the immigrant–native differences in hospitalization to varying degrees across immigrants’ regions of birth. These factors explained the least proportion of this difference among the groups most affected by COVID-19. This highlights the need to continue identifying factors underlying immigrants’ higher risks of adverse COVID-19 outcomes.

Ma et al. quantify the role of several factors in explaining COVID-19 hospitalization differences between Swedish- and foreign-born individuals using a decomposition method. The findings reveal that the same set of factors influence COVID-19 hospitalization disparities to varying degrees depending on immigrants’ region of birth, and that these factors account for a smaller share of the disparities among the groups most affected by the pandemic.