A 15-year registry based follow up study of site specific cancer mortality among immigrants with type 2 diabetes in Sweden

Cancer is a leading cause of death among individuals with type 2 diabetes (T2D), and immigrants in Europe face a higher T2D risk than native populations. We investigated mortality disparities in overall and eight specific T2D-related cancers among immigrants and native Swedes diagnosed with T2D between 2006 and 2021. An open cohort of 478,607 individuals aged ≥ 35 years at the time of T2D diagnosis (28% first-generation [G1] and 6% second-generation [G2] immigrants) was followed until December 31, 2023. Flexible parametric survival models were used to estimate hazard ratios (HRs), stratified by age at arrival and duration of residence for G1 immigrants. G1 immigrants, except those from Nordic countries, generally had lower overall cancer mortality than natives. However, mortality risks for specific cancers converged toward those of natives with longer residence in Sweden, and notably liver and endometrial cancer mortality were higher among those who arrived early in life compared with natives. In G2 immigrants, kidney and endometrial cancer mortality rates were elevated, particularly for those with Western (HR = 1.63) and Nordic (HR = 1.82) parental origins, respectively. Mortality rates from colorectal and liver cancers also appeared to increase among those more recently diagnosed with T2D. These findings underscore the need for strengthening integrated diabetes and cancer care and tailored support services for high-risk immigrant populations.