Examining the exhaled levels of hydrogen peroxide in rheumatoid arthritis: a pilot study

Previous studies have assessed airway inflammation in rheumatoid arthritis by using bronchoalveolar lavage (BAL).1,2 To widen the scope of the study, a biomarker that is less invasive and less expensive is necessary. Recent studies have shown that exhaled breath condensate (EBC), a measure that is minimally invasive and substantially less expensive than BAL, can be used to assess inflammation in the lower respiratory tract.3,4 To assess the utility of this measure, we compared the levels of EBC hydrogen peroxide (H2O2) in patients with rheumatoid arthritis with values in controls. Patients with rheumatoid arthritis (n = 22) meeting the disease classification criteria5 and controls (n = 23) were studied. As smoking influences EBC measures of inflammation,6 we assessed smoking status (current smoker v non-smoker), excluding subjects self-reporting a diagnosis of chronic …