Living in a neighbourhood where people feel safe and supported is linked to a reduced risk of psychosis among Stockholm residents – but only for people of Swedish or European origin. This is shown in a new study from Karolinska Institutet and UCL published in the journal Nature Mental Health. For people of North African or Middle Eastern origin, an increased risk of psychosis was seen in the same neighbourhoods.

“Our results indicate that high personal trust in the residential area does not automatically benefit everyone. To promote mental health among the entire population, we need to create inclusive environments for everyone,” says Anna-Clara Hollander, associate professor at the Department of Global Public Health and co-author from Karolinska Institutet, together with Cecilia Magnusson and Christina Dalman, professors at the same department.

The explanation may lie in who experiences trust in the neighbourhood.

“The levels of personal trust measured in the study were based primarily on responses from people with Swedish-born parents. This means that people from different backgrounds may not have the same experiences or access to social networks that foster safety and trust,” says the study’s last author, James B. Kirkbride, professor of psychiatric and social epidemiology at UCL (University College London), and lead investigator on the study.

Social capital in residential areas

In a comprehensive population study, the researchers investigated how different forms of social capital in residential areas affect the risk of developing serious mental illnesses, such as psychosis and bipolar disorder. The study is based on data from over 1.4 million people born in Sweden and living in Stockholm County, who were followed for up to 15 years.

The researchers focused on three types of social capital: political trust, welfare trust and personal trust, i.e. the experience of being able to get help when needed and feeling safe in one’s neighbourhood.

The results show that higher levels of personal trust in the neighbourhood were associated with either a reduced or increased risk of developing psychotic disorders and bipolar disorder without psychosis, depending on the person’s origin. Among residents with parents from Sweden or Europe, high personal trust had a protective effect, while the opposite effect was seen among residents with parents from North Africa and the Middle East.

Provides important clues

The researchers emphasise that the results cannot be interpreted as a causal relationship, but that they provide important clues as to how social factors affect mental health.

The study also shows that political and welfare-related trust had no clear link to mental illness.

Previous research has shown that foreign-born people living in Sweden and other high-income countries have an increased risk of developing psychosis, schizophrenia and other psychotic disorders. There is also evidence suggesting that the risk is lower among people living in areas with a high proportion of individuals from the same country of origin.

The study was conducted in collaboration with Region Stockholm. It was funded by the Swedish Research Council, Forte, the Wellcome Trust and the Royal Society, among others. James B. Kirkbride has received consultancy fees from Roche and the Health Services Executive, Ireland. No other conflicts of interest have been reported.