Risk of venous thromboembolism in ankylosing spondylitis: a general population-based study.

BACKGROUND: Venous thromboembolism (VTE), including pulmonary embolism (PE) and deep venous thrombosis (DVT), can be life threatening. An increased frequency of VTE has been found in inflammatory conditions. To date, evidence assessing whether this risk is also greater in patients with ankylosing spondylitis (AS) is scarce. METHODS: Using the provincial British Columbia, Canada healthcare database that encompasses all residents within the province, we conducted matched cohort analyses of incident PE, DVT and overall VTE among incident cases of AS and compared them with individuals randomly selected from the general population without AS. We calculated incidence rates (IRs) of VTE and multivariable analyses after adjusting for traditional risk factors using Cox models. RESULTS: Among 7190 incident cases of AS, 35 developed PE and 47 developed DVT. IRs of PE, DVT and overall VTE per 1000 person-years for patients with AS were 0.79, 1.06, 1.56 compared with 0.40, 0.50, 0.77 in the control cohort. Corresponding fully adjusted HRs (95% CI) of PE, DVT and VTE were 1.36 (0.92 to 1.99), 1.62 (1.16 to 2.26) and 1.53 (1.16 to 2.01), respectively. The risks of PE, DVT and VTE were highest in the first year of diagnosis with HR (95% CI) of 2.88 (0.87 to 9.62), 2.20 (0.80 to 6.03) and 2.10 (0.88 to 4.99), respectively. CONCLUSIONS: These findings demonstrate an increased risk of VTE in the general AS population. This risk appears the most prominent in the first year after diagnosis.

The risk of pulmonary embolism and deep vein thrombosis in rheumatoid arthritis: a UK population-based outpatient cohort study.

BACKGROUND: Recent hospital-based studies have suggested a sixfold increased risk of pulmonary embolism (PE) in rheumatoid arthritis (RA) in the year following admission. We evaluated the risk of PE and deep vein thrombosis (DVT) and associated time trend among RA patients (84.5% without a history of hospitalisation during the past year) derived from the general population. METHODS: We conducted a cohort study using an electronic medical records database representative of the UK general population, collected from 1986 to 2010. Primary definitions of the RA cohort (exposure) and PE/DVT outcomes required physician diagnoses followed by corresponding treatments. We estimated relative risks (RRs) of PE and DVT compared with a matched non-RA comparison cohort, adjusting for age, sex, smoking, body mass index, comorbidities and hospitalisations. RESULTS: Among 9589 individuals with RA (69% female, mean age of 58 years), 82 developed PE and 110 developed DVT (incidence rates, 1.5 and 2.1 per 1000 person-years). Compared with non-RA individuals (N=95 776), the age-, sex- and entry-time-matched RRs were 2.23 (95% CI 1.75 to 2.86) for PE and 2.20 (CI 1.78 to 2.71) for DVT. Adjusting for other covariates, the corresponding RRs were 2.16 (CI 1.68 to 2.79) and 2.16 (CI 1.74 to 2.69). The time-specific RRs for PE were 3.27, 1.88 and 2.35 for follow-up times of <1 year, 1-4.9 years, and ≥5 years, and corresponding RRs for DVT were 3.16, 1.82 and 2.32. CONCLUSIONS: This population-based study indicates an increased risk of PE and DVT in RA, supporting increased monitoring of venous-thromboembolic complications and risk factors in RA, regardless of hospitalisation.

Risk of incident cardiovascular events in patients with rheumatoid arthritis: a meta-analysis of observational studies.

OBJECTIVE: To determine the magnitude of the risk of incident cardiovascular disease (CVD; fatal and non-fatal), including acute myocardial infarction (MI), cerebrovascular accidents (CVA) and congestive heart failure (CHF), in patients with rheumatoid arthritis (RA) compared to the general population through a meta-analysis of controlled observational studies. METHODS: The authors searched the Medline, Embase, LILACS and Cochrane databases from their inception to June 2011. Observational studies meeting the following criteria were included: (1) prespecified RA criteria; (2) predefined CVD criteria for incident CVD (MI, CVA or CHF); (3) a comparison group; and (4) RR estimates, 95% CI or data for calculating them. The authors calculated the pooled RR using the random-effects model and tested for heterogeneity using the bootstrap version of the Q statistic. RESULTS: Fourteen studies comprising 41 490 patients met the inclusion criteria. Overall, there was a 48% increased risk of incident CVD in patients with RA (pooled RR 1.48 (95% CI 1.36 to 1.62)). The risks of MI and CVA were increased by 68% (pooled RR 1.68 (95% CI 1.40 to 2.03)) and 41% (pooled RR 1.41 (95% CI 1.14 to 1.74)). The risk of CHF was assessed in only one study (RR 1.87 (95% CI 1.47 to 2.39)). Significant heterogeneity existed in all main analyses. Subgroup analyses showed that inception cohort studies were the only group that did not show a significantly increased risk of CVD (pooled RR 1.12 (95% CI 0.97 to 1.65)). CONCLUSIONS: Published data indicate that the risk of incident CVD is increased by 48% in patients with RA compared to the general population. Sample and cohort type influenced the estimates of RR.