Abstract
INTRODUCTION: Cancer is a major public health challenge in Germany with significant socioeconomic inequalities in incidence and mortality. However, there is only limited research on the incidence of diagnosis-specific cancers and related inequalities among socioeconomic groups within the working-age population. This study aims to address this gap by analysing how the incidence of common cancers depends on individual- and area-level socioeconomic characteristics among working-age women and men. METHODS: Using a prospective cohort design based on anonymised German statutory health insurance data, this study examined a cohort of 2.23 million individuals aged 25-67 years over a five-year period (2015-2019). Individual socioeconomic position was assessed using educational attainment and occupational skill levels, while area-level deprivation was determined using a composite socioeconomic index. Incidence rates were estimated per 100,000 person-years at risk, age-standardised to the 2013 European standard population. Hazard ratios were calculated using multilevel Cox proportional hazards models. RESULTS: The analysis revealed 50,276 newly diagnosed cancer cases during the study period. Lower education, lower occupational skill levels and higher area-level deprivation were associated with a higher incidence of stomach, lung, colorectal, prostate, breast and cervical cancer, but a lower incidence rate of malignant melanoma of the skin. After mutual adjustment of the socioeconomic indicators, higher hazard ratios of lung cancer were found for men with lower educational (HR = 2.8, 95%CI:2.3-3.5) and occupational skill levels (HR = 2.8, 95%CI:2.3-3.5) and for women with lower education (HR = 2.3, 95%CI:1.7-3.1). Lower occupational skill levels in both sexes (women HR = 0.6, 95%CI:0.5-0.7; men HR = 0.7, 95%CI:0.6-0.9) and lower educational levels in men (HR = 0.7, 95%CI:0.6-0.8) were independently associated with a lower risk of malignant melanoma. For area-level deprivation, we observed a higher risk of stomach (women 1.6, 95%CI:1.2-2.0; men HR = 1.3, 95%CI:1.1-1.6) and lung cancer (women HR = 1.3, 95%CI:1.1-1.5; men HR = 1.5, 95%CI:1.3-1.7) in more deprived areas, even after adjusting for individual-level socioeconomic characteristics. In contrast, a higher risk of skin melanoma was observed in less deprived areas after individual-level socioeconomic adjustments (women and men HR = 0.6, 95%CI:0.5-0.7). CONCLUSIONS: Our findings suggest that strategies to prevent cancer in the working-age population should take more account of the unequal structural conditions in which people work and live. The study shows that area-level socioeconomic deprivation has explanatory power for unequal cancer risks beyond the individual characteristics of socioeconomic position.