Intersectional inequalities in health in Germany: The effects of sex, education, and migration

Abstract Background Persisting health inequalities for females, those with less education, and those with migration background have been documented in Germany and Europe, but few studies have used intersectional methods to assess the combined effect of these identities on self-rated health (SRH). Methods Using baseline data from 191,836 German National Cohort (NAKO) participants, we created three intersectional exposure variables combining binary sex, level of education, and migration variables (any migration, Turkish, and ethnic German resettler backgrounds). We used multinomial logistic regression to produce relative risk (RR) ratios for poor SRH as compared to good SRH while controlling for age, household size, and study site. We assessed additive interaction by computing two- and three-way relative excess risk due to interaction (RERI) measures. Results Compared to university-educated non-migrant males, the RR of poor SRH increased as the number of disadvantaged identities increased. Among those without university and with any migration background, males had a RR of 2.27 (95% CI 2.11-2.45) and females a RR of 2.59 (95% CI 2.42-2.77). Inequalities were most extreme for females without university who were Turkish (RR 5.86, 95% CI 4.98-6.89) or resettlers (RR 3.44, 95% CI 2.89-4.10). We found several significant superadditive RERI effects. The total RERI for having any migration background, being female, and not being university educated was 0.65 (95% CI 0.45-0.84), indicating that the interaction of these identities was associated with a 65% increase in risk in addition to the separate risk of each identity. The RERI for Turkish females without university was especially notable, indicating a 369% increase in risk (Total RERI 3.69, 95% CI 2.65-4.72). Conclusions We found intersectional inequalities in SRH by sex, education, and migration. The interaction between disadvantaged identities increased the risk of poor SRH beyond the added risk of each individual identity. Key messages • We found intersectional inequalities in health by sex, education, and migration. The interaction of these identities increased the risk of poor health beyond the separate risk of each identity. • Future research should explore how intersectional inequalities may affect the progression towards worse health over time. Policymakers should be aware of nuanced differences between subgroups.