Background: Rheumatoid Arthritis (RA) patients have a higher mortality and morbidity than the general population, related to cardiovascular disease (CVD). RA patients experience an increased risk of myocardial infarction, due to traditional risk factors and inflammation. Systemic inflammation is evident prior to the onset of clinical RA but not osteoarthritis (OA), we hypothesized that cardiovascular events and risk factors would occur prior to diagnosis of RA.
Methods: The HUNT surveys (1995-1997 and 2006-2008) were conducted in Nord-Trøndelag Norway. Information of RA or OA diagnosis ,were obtained from 36493 patients. Risk factors of age, sex, smoking, BMI, blood pressure, diabetes and previous CVD were evaluated in subjects that did not have RA or OA at baseline.
Results: 33567 individuals without RA or OA at baseline were mean (SD) age 46 (13) years old, 54% female, 50% current or ex-smokers, had BMI 26.1 (3.8) kg/m2, 3.2% had previous CVD, 1.4% had diabetes, 36% had hypertension. In this cohort, 786 (2.3%) individuals self-reported RA, 3586 (10.7%) self-reported OA at follow-up. Female were 41% and 136% more likely to develop RA and OA respectively. Individuals with previous CVD were 41% more likely to develop RA (p=0.03), but not OA.
Cardiovascular outcomes and associated risk factors were evaluated in patients diagnosed with RA (n=429), OA (n=2497) at baseline and follow-up. Adjusted for cardiovascular risk factors, RA subjects had a increased risk of stroke 69% (p=0.02), MI 45%(p=0.12) during follow-up. OA subjects had a 35% increased risk of angina (p=0.003), no vascular events.
Conclusion: These data suggest that subjects developing RA and OA among this population share common risk factors, but only RA is pre-dated and associated with increased cardiovascular events. The development of RA at population level is associated with previous cardiovascular events and suggests the need for screening individuals with events for auto-antibodies and inflammatory features of RA.