Cardiovascular Risk Factors before Onset of Rheumatoid Arthritis Are Associated with Cardiovascular Events after Disease Onset: A Case-Control Study.

BACKGROUND: The increased comorbidity and mortality in rheumatoid arthritis (RA) patients are largely due to cardiovascular disease (CVD). Previously, we demonstrated increased frequencies of risk factors for CVD (elevated body mass index (BMI), elevated apoliprotein (Apo) B:ApoA1 ratio, and smoking) in pre-RA individuals compared with matched controls.

OBJECTIVES: Assess the impact of traditional CV risk factors present before the onset of RA on the risk of CV events (CVE) after diagnosis in comparison with matched controls.

METHODS: A case-control study including 521 pre-symptomatic individuals and 1566 controls identified within the Health Surveys of the Medical Biobank was performed. CVD risk factors were hypertension, elevated ApoB:A1 ratio, BMI, diabetes, and smoking. Information on comorbidities was requested from the Swedish National Patient Register and Cause of Death Register.

RESULTS: Pre-RA individuals had a higher risk of future CVE compared with matched controls (HR [95% CI] 1.70 [1.31-2.21]), which remained after adjustments for risk factors for CVD (HR [95% CI] 1.73 [1.27-2.35]). Most risk factors were associated with CVE after diagnosis, and a combination resulted in a higher risk in RA compared with controls; two risk factors, HR [95% CI] 2.70 [1.19-6.13] vs. 1.26 [0.75-2.13]; and three to four risk factors, HR [95% CI] 6.32 [2.92-13.68] vs. 3.77 [2.34-6.00].

CONCLUSIONS: Risk factors for CVD present in pre-RA individuals were associated with future CVE, and even after adjustments for these risk factors and treatments after RA onset, pre-RA individuals had a higher risk of CVE compared with controls. These findings further highlight the importance of the early assessment of risk for CVD.