The increased risk for cardiovascular disease (CVD) in rheumatoid arthritis (RA) is well known and inflammation appears to play a pivotal aetiological role. There is now substantial interest in whether or not psoriatic arthritis (PsA) is also associated with an enhanced cardiovascular (CV) risk. However, data on CVD in PsA is limited.1,–,3 The aim of this comparative study was to determine the prevalence of non-fatal CVD in patients with PsA compared with patients with RA and to investigate the risk factors of CVD in PsA.

In 2008 a CV questionnaire was sent to all 753 patients with PsA aged 50–75 years registered at our centre.4 As a comparator group, data from 353 randomly selected patients with RA aged 50–75 years (the CARdiovascular research and RhEumatoid arthritis study) were used.5 In all patients CVD was defined as a history of myocardial infarction, stroke and/or transient ischaemic attack verified by written documentation of the event. To study the CV risk factors, each patient with PsA with a history of CVD (cases) and three randomly selected age- and sex-matched patients with Psa without CVD (controls) attended the outpatient clinic for clinical investigation. Logistic regression was used to perform the analysis.

The response rate on the CV questionnaire was 65%. Women were less likely to respond than men (p=0.008). The prevalence of CVD was 10% in patients with PsA compared with 12% in patients with RA (OR 0.78; 95% CI 0.51 to 1.20; p=0.264). The age- and sex-stratified OR showed no significant difference between patients with RA and those with PsA (table 1). The results of cross-sectional analysis are shown in table 2.

This study demonstrates for the first time that the prevalence of CVD in PsA resembles the CV risk of RA. Furthermore, in our cross-sectional analysis we found a significant association between severity of disease measured by Disease Activity Score using 28 joint counts and disability index measured by Health Assessment Questionnaire and a history of CVD.

Many hypotheses exist to explain the increased CV risk in inflammatory rheumatic diseases, including the increased prevalence of traditional CV risk factors and inflammation which contribute considerably to all stages of atherosclerosis.1 6,–,9 A major area of research is to investigate the mechanisms by which inflammation interacts with conventional CV risk factors and enhances the atherosclerosis.

The limitations of this study are low response rate on the CV questionnaire and lack of direct comparison between patients with PsA and the general population. Owing to the response rate of 65%, the CV prevalence in PsA might be overestimated as patients with CV events were possibly more willing to participate. Otherwise, when conformation of the CV event was lacking, the patient was considered as a non-event which possibly led to underestimation of the prevalence rate. In addition, this study was limited to patients aged 50–75 years and non-fatal CV events. The results might be different for younger/older subjects or fatal CV events. Our findings need to be confirmed in other larger studies but, despite the limitations, this study emphasises the increased CV burden in PsA and, for the first time, we have shown that its magnitude resembles that of RA.