# Inequalities in somatic comorbidities among immigrants and Norwegians with and without common mental disorders: a national register study

## TL;DR

This study finds that immigrants with mental disorders in Norway face higher risks of certain physical health issues compared to Norwegians with similar conditions.

## Contribution

The study reveals novel disparities in somatic comorbidity risks among immigrant groups with mental disorders compared to Norwegians.

## Key findings

- Individuals with common mental disorders had higher somatic disease risks regardless of immigrant status.
- Non-Western immigrants with mental disorders had higher risks of CVD, hypertension, and diabetes than Norwegians with mental disorders.
- Sub-Saharan African immigrants with mental disorders had increased risk for viral hepatitis.

## Abstract

Comorbidity between mental disorders and somatic diseases exacerbates health outcomes and contributes to premature mortality. However, differences in this comorbidity among immigrant groups compared to the majority population are unclear. This study aims to examine disparities in the risk relationship between common mental disorders (CMDs) and somatic diseases among the majority population (Norwegians) and various immigrant groups.

This national register study uses information from 3 142 925 residents aged 18+on diagnosed CMDs and selected somatic diseases for years 2008–2016. Poisson regression models were used to study the association between CMD and somatic diseases (i.e., cardiovascular diseases (CVDs), endocrine and metabolic diseases, cancer, and infectious diseases). Differences in risk between Norwegians and immigrant groups were investigated by introducing interaction terms between CMD and immigrant background.

Individuals with CMDs had a higher risk for all somatic diseases compared to those without, regardless of immigrant status. Immigrant groups varied in comorbidity, with those without CMDs showing similar or lower risk compared to Norwegians. However, immigrants with CMDs from non-Western countries (i.e., Eastern Europe, sub-Saharan Africa, South Asia) had a significantly higher probability of developing CVD, hypertension, and diabetes mellitus than Norwegians with CMDs. Additionally, SSA immigrants with CMDs also had a higher risk for viral hepatitis.

Findings suggest that immigrant groups experience varying degrees of comorbidity, which underscores the need for tailored healthcare interventions to address these disparities effectively.

The online version contains supplementary material available at 10.1007/s00127-025-02892-6.