Physical inactivity and arterial dysfunction in patients with rheumatoid arthritis

Objectives: The increased risk of cardiovascular (CV) disease associated with rheumatoid arthritis (RA) is partly attributable to chronic inflammation, but traditional CV risk factors such as physical inactivity are also likely to be important. This study assessed the cross-sectional relationship between physical activity (PA) and arterial dysfunction in patients with RA. Methods: Participants free of overt arterial disease aged 40-65 years were recruited from a consecutive series of RA patients attending a rheumatology clinic. A research nurse measured the 'augmentation index' (AIX%) on a single occasion (a higher AIX% indicates arterial dysfunction) using SphygmoCor radial pulse wave analysis (PWA) according to current recommendations. Participants provided a fasting blood sample and self-completed a patient questionnaire that included the modified Godin PA score (mGPAS). Analysis was adjusted for age, sex, CV and rheumatological factors using multiple linear regression. Results: Among 114 patients (mean age 54 years, median arthritis duration 10 years, 82% women), mean AIX% was 31.5 (SD 7.7) and median mGPAS 15 (IQR 10-35). AIX% was correlated with mGPAS (rho -0.21, p = 0.02). AIX% decreased with more frequent vigorous PA. On unadjusted analysis, a 10-point higher mGPAS was associated with a -0.9 [95% confidence interval (CI) -1.3 to -0.4, p = 0.0005] lower AIX%. On adjusted analysis, the reduction was attenuated to -0.5 (95% CI -0.8 to -0.1, p = 0.03). Conclusions: A higher level of self-reported PA in RA patients is associated with a lower level of arterial dysfunction independently of other CV and rheumatological factors. Longitudinal studies are required to demonstrate that increased PA improves arterial dysfunction in RA patients.