Fig. 2

The association between incident RA and a combination of PRS and RDW. The groups of RDW were defined by the quartiles. The genetic risk categories were defined according to PRS as low (<20%), intermediate (20–80%), high (>80%). Joint association between combined genetic risk categories and RDW groups and RA was estimated by Cox Proportional Hazards models with age as the time scale, adjusted for sex, BMI, total physical activity (TPA), Townsend deprivation index, healthy diet score, and the first five genetic principal components. The error bars represent 95% confidence interval of hazard ratio. PRS polygenic risk score