Tumour necrosis factor α blockade reduces circulating N-terminal pro-brain natriuretic peptide levels in patients with active rheumatoid arthritis: Results from a prospective cohort study

Background: Patients with rheumatoid arthritis (RA) are at increased risk of heart failure and vascular events. Small increases in circulating N-terminal pro-brain natriuretic peptide (NT-proBNP) are associated with an increased risk of a cardiovascular event, and high levels signal left ventricular dysfunction. Data on the effects of tumour necrosis factor α(TNFα) blocking agents on circulating NT-proBNP levels in patients with active RA are lacking but may be informative. Methods: 171 consecutive patients with RA (28-joint disease activity score >3.2) without congestive heart failure (NYHA class III or IV) were scheduled to receive adalimumab once every 2 weeks. Serum NT-proBNP concentrations were measured simultaneously on stored baseline and 16-week samples. Paired sample t tests were used to observe differences in biomarkers before and after adalimumab administration. Correlations between the biomarkers and changes in circulating log NT-proBNP levels were evaluated with the Pearson test and multivariable linear regression analyses of correlates were performed (forward selection procedure). Results: Circulating levels of NT-proBNP decreased significantly after 16 weeks of adalimumab administration (median NT-proBNP 83.0 pg/ml vs 69.5 pg/ml, p=0.004). Changes in NT-proBNP levels were associated with changes in pulse pressure (r=0.18, p=0.02), systolic blood pressure (r=0.16, p=0.04) and erythrocyte sedimentation rate (r=0.18, p=0.02). On multivariable analysis, changes in pulse pressure and erythrocyte sedimentation rate remained independently associated with changes in circulating NT-proBNP levels. Conclusions: These observations show that blocking TNFα in patients with RA without evident heart failure decreases NT-proBNP levels by about 18%. This suggests no treatment-induced deterioration in cardiac function and a potential cardiovascular risk benefit.