Impact of neighborhood income inequality on adolescents' mental health. Results from the STARS study

Over recent decades, there has been a simultaneous increase in income inequality and adverse mental health outcomes among adolescents in Western countries and especially in Sweden. Prior research on the relationship between income inequality and mental health has primarily focused on studies involving adults, yielding diverse findings regarding the nature of their association. Given the importance of relationships and comparisons to peers in immediate vicinity, we aimed to investigate the impact of neighborhood income inequality on mental health problems among seven-graders in Western Sweden. We used data collected in the STARS (STudy of Adolescence Resilience and Stress) cohort. A total of 1958 adolescents (mean age 13.6, SD = 0.4, 44% male) in 313 Demographic Statistics Areas (DeSO) were included. Adolescents answered questionnaires regarding stress and psychosomatic symptoms. Neighborhood income inequality was measured as DeSO-level's P90/P10 ratio, defined as the ratio between the 10th (highest) and the 1st (lowest) income decile. In a multilevel linear regression analysis, we found that higher neighborhood income inequality was related to lower stress and psychosomatic symptom scores after controlling for sex, individual parental income, and mean income and child poverty rate at DeSO-level. The associations did not differ significantly among DeSO-areas with different income or child poverty rates. Sex-specific-analysis revealed that the inverse association between income inequality and stress and psychosomatic symptoms was stronger in females than in males, but not significantly so. In summary, this study provided evidence supporting an association between higher neighborhood income inequality and reduced levels of seven-graders' stress and psychosomatic symptoms.