The influence of socioeconomic disparities on the association of physical behavior with incident type 2 diabetes

To evaluate the influence of socioeconomic status (SES) on the associations of moderate to vigorous physical activity (MVPA), light intensity physical activity (LIPA), sedentary behavior, and sleep duration with incident type 2 diabetes (T2D). The analysis included 69,461 participants from the UK Biobank who completed an accelerometer-based physical activity measurement. Individual-level SES was assessed via latent class analysis of household income, employment status, and education qualifications. The area-level SES was determined through the Townsend Deprivation Index. The additive hazard model and Cox proportional hazards model were employed to estimate the risk of T2D. After a median follow-up of 6.7 years, 1,252 cases of incident T2D were documented. The associations between physical behaviors and T2D risk differed significantly by SES. Compared with individuals with higher SES, those with lower SES presented greater increases in T2D risk associated with low MVPA (68 vs. 31 cases per 10,000 person-years; p for interaction = 0.030), high sedentary behavior (24 vs. 1 cases per 10,000 person-years; p for interaction < 0.001), and short sleep duration (23 vs. 5 cases per 10,000 person-years; p for interaction = 0.003). Area-level SES also modified the relationship between low MVPA and T2D risk on both additive and multiplicative scales (p for interaction < 0.001), with stronger effects observed in socioeconomically disadvantaged groups. Addressing insufficient MVPA, prolonged sedentary behavior, and inadequate sleep among individuals with lower SES could significantly reduce the number of T2D cases, highlighting the importance of targeted public health interventions to mitigate disparities in T2D incidence.