CRP and rheumatoid arthritis: The amount of missing data for covariates for the 868 patients were: age (n = 8 missing values), HDL-cholesterol (n = 61), LDL cholesterol (n = 70), diabetes status (n = 7), smoking status (n = 9), family history of IHD (n = 10), RA duration (n = 9), DAS28 (n = 31), CRP (n = 24), steroid dosage (n = 2), and BMI (n = 16).