Venous thromboembolism (VTE) is an increasing concern in rheumatoid arthritis (RA) with little known about risk factors. We aimed to compare risk factors for unprovoked VTE and atherosclerotic cardiovascular disease (ASCVD) in patients with RA and to assess subsequent ASCVD risk after an unprovoked VTE.
People with RA participating in a US-wide longitudinal observational registry from 1998 to 2018 were assessed for incident unprovoked VTE (deep venous thrombosis and pulmonary emboli not associated with cancer, recent surgery, hospitalisation, fracture and pregnancy) and ASCVD (myocardial infarction and stroke) validated from hospital/death records. Risk factors for VTE and ASCVD and the risk of ASCVD after an unprovoked VTE were determined using Cox proportional hazards models.
During median (IQR) 4 (1.5-7) years of follow-up in 31 366 patients with RA, 539 unprovoked VTE and 1648 ASCVD events were identified. The adjusted models showed increased VTE and ASCVD risk with older age, male sex, comorbidities, prior fracture, worse disability, higher disease activity and glucocorticoids. Traditional cardiovascular disease risk factors were common in both ASCVD and VTE but only increased ASCVD risk with obesity as the exception (VTE HR (95% CI), 1.46 (1.13-1.87)) and ASCVD, 0.58 (0.50-0.68)). ASCVD risk doubled after an unprovoked VTE (HR (95% CI), 2.05 (1.43-2.95)).
Our findings suggest that unprovoked VTE is mediated by inflammation of RA and may be considered a spectrum of pan-cardiovascular syndrome.