Introduction: Perceived discrimination is associated with risk factors for type 2 diabetes, including measures of adiposity. However, the relationship between perceived discrimination and incident diabetes is unknown.
Objectives: To determine whether perceived discrimination is related to incident diabetes, and whether this association varies by race/ethnicity, age or sex.
Methods: Included in this analysis were 5,310 MESA participants aged 45-84 years, without a history of diabetes at baseline. Perceived discrimination was measured using the Lifetime Discrimination scale, which assessed experiences of unfair treatment in 6 life domains (e.g. fired or denied a promotion, unfair treatment by police, not hired for a job, having life made difficult by neighbors). Participants were also asked to attribute their experiences of discrimination to various factors (e.g. race/ethnicity, age, sex, religion). Incident diabetes was identified at four follow-up examinations as fasting glucose ≥126 mg/dL or use of diabetes medications. Multivariable-adjusted Cox proportional hazard regression was used to model lifetime discrimination as a continuous and categorical variable (0, 1, ≥2 domains).
Results: A total of 654 incident diabetes cases accrued over a median follow-up of 9.4 years (range 0.9-11.4). Lifetime discrimination reported in ≥ 2 domains (versus none) was associated with a 34% increased risk of incident diabetes, after adjustment for potential confounders or mediators (Table). Similar patterns were observed when we evaluated discrimination attributed to race/ethnicity only, or to a combination of other sources. There were no differences in the strength of association by race/ethnicity, age or sex.
Conclusions: Lifetime discrimination was associated with increased risk of incident diabetes, regardless of attribution. These associations were independent of obesity, behavioral and psychosocial factors. Future research is needed to explore the mechanisms of the discrimination-diabetes relationship.