APOB and rheumatoid arthritis: BMI ≥ 25.0, elevated ApoB/ApoA1 ratio and smoking were all significantly associated with increased risk for development of RA in multivariable conditional logistic regression models in younger individuals (OR = 1.45 (1.04–2.02), OR = 1.39 (1.00–1.93) and OR = 2.11 (1.51–2.95), respectively) (Table 3).