Researchers examined the effects of antirheumatic treatment with Methotrexate (MTX) and tumor necrosis factor inhibitors (TNFi)—with or without MTX co-medication—on the serum N-terminal pro-brain natriuretic peptide (NT-proBNP) levels, as well as inflammatory markers, in patients with autoimmune arthritis. Their report was published in PLoS One.
The study’s lead author, Thao Nguyen, stated that their findings linked NT-proBNP levels to inflammatory markers. However, despite he and his collaborators’ observation that antirheumatic therapies significantly improved these markers, the therapies themselves did not appear to affect participants’ NT-proBNP levels.
The trial included 115 patients, of which 64 had rheumatoid arthritis (RA), 31 had psoriatic arthritis (PsA), and 20 had ankylosis spondylitis (AS). Clinical and laboratory outcomes were evaluated at baseline and after six weeks and six months of treatment.
NT-proBNP levels did not change significantly after six weeks (p = 0.939) or six months (p = 0.485) of antirheumatic treatment. There was no statistically significant difference in effect on NT-proBNP levels between MTX monotherapy and TNFi regimen, although there was a modest improvement from six weeks to six months in the MTX-only treatment group (median difference = –18.2, 95% confidence interval [CI] = –32.3 to –4.06, p = 0.013). Changes in NT-proBNP after treatment were also positively associated with changes in C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR).
The article did acknowledge several limitations of their study, including, among others, the observational design, the lack of a healthy control, and the fact that choice of therapy was made by the patient and their doctor, which could have introduced selection bias.
The authors posited that the study’s results demonstrated an association between inflammation and cardiac function and NT-proBNP. Furthermore, while NT-proBNP levels did not improve after six months of therapy, they were not negatively impacted despite significant improvements in participants’ inflammatory markers. “As patients with AA may be at risk for cardiac dysfunction and future CV events, further research is needed to define if NT-proBNP might be a good biomarker for predicting HF in AA patients,” the researchers concluded.
Source: PLoS One