The utility of maximal oxygen uptake in assessment of cardiovascular risk in female patients with rheumatoid arthritis without associated lung disease

Abstract

Introduction: The gold standard method for assessment of cardiorespiratory competence is the maximal oxygen uptake (VO2 max) examination.

Objective: To evaluate VO2 max as a marker of cardiovascular disease in rheumatoid arthritis (RA) and its relation with cardiovascular disease (CVD) in such cohort of female patients with rheumatoid arthritis without associated lung disease.

Patients and Methods: 132 female RA patients were assessed for cardiopulmonary fitness with a VO2max testing. 100 healthy females were recruited as control group. Exclusion of patients with pulmonary fibrosis by using HRCT. Traditional CVD risk factors and disease characteristics and their correlation with VO2 max were assessed.

Results: Based on VO2 max mean, patients were classified into three groups; unfit (<16.72 ml/kg/min), fair (16.73-25.6 ml/kg/min) and average fitness (>25.6 ml/kg/min). Patients were significantly worse VO2 max mean [(21.28±6.96) ml/kg/min] compared to control subjects. Patients with poor VO2 max level were more likely be older, hypertensive, had family history of CVD, high BMI with high mean of FRS. Significant differences were detected between the fitness subgroups in mean of carotid IMT and presence of carotid plaques. Long duration of RA, uncontrolled disease activity, high HAQ, high CRP and positive anti-CCP antibodies were correlated significantly with reduced VO2 max.

Conclusion: VO2 max test can be used as a surrogate cardiovascular disease marker in RA patients. VO2 max can be used as a noninvasive test to detect and quantify fitness defects in RA patients at increased risk of CVD.