Effect of rheumatoid factor on mortality and coronary heart disease

Objective An association between rheumatoid factor (RF) and increased mortality has been described in individuals with rheumatoid arthritis. The objective of this study was to determine the effect of RF on mortality and coronary heart disease (CHD) in the general population. Methods Subjects were participants in a population-based study focused on cardiovascular disease who attended for a study visit during the years 1974-84. RF was measured and information obtained on cardiovascular risk factors, joint symptoms and erythrocyte sedimentation rate (ESR). The subjects were followed with respect to mortality and incident CHD through 2005. Adjusted comparison of overall survival and CHD event-free survival in RF-positive versus RF-negative subjects was performed using Cox proportional hazards regression models. Results Of 11 872 subjects, 140 had positive RF. At baseline RF was associated with diabetes mellitus and smoking and inversely associated with serum cholesterol. RF-positive subjects had increased all-cause mortality (HR 1.47, 95% CI 1.19 to 1.80) and cardiovascular mortality (HR 1.57, 95% CI 1.15 to 2.14) after adjusting for age and sex. Further adjustment for cardiovascular risk factors and ESR only modestly attenuated this effect. An increase in CHD among the RF-positive subjects did not reach statistical significance (HR 1.32, 95% CI 0.96 to 1.81, adjusted for age and sex). Subjects with RF but without joint symptoms also had increased overall mortality and cardiovascular mortality (HR for overall mortality 1.33, 95% CI 1.01 to 1.74, after adjustment). Conclusion In a general population cohort, RF was associated with increased all-cause mortality and cardiovascular mortality after adjustment for cardiovascular risk factors, even in subjects without joint symptoms.