Electrocardiographic changes in spondyloarthritis and use of anti-TNF-α drugs: a retrospective study with 100 patients

OBJECTIVE: To investigate the prevalence of electrocardiographic changes in patients with spondyloarthritis and to correlate these changes with use of anti-tumor necrosis factor-alpha (TNF-α) drugs and HLA-B27 positivity. METHODS: Retrospective study including 100 patients diagnosed with spondyloarthritis according to Assessment of SpondyloArthritis International Society (ASAS) criteria and 50 controls. Epidemiological and clinical features, results of inflammatory activity tests, HLA-B27 positivity, and medication use data were extracted from medical records. Disease activity was assessed using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). All participants were submitted to electrocardiogram performed using a 12-lead device; rhythm, heart rate, conduction disorders and QT interval corrected using the Bazett formula were analyzed. RESULTS: Of 100 patients with spondyloarthritis, 51 were on anti-TNF-α drugs and 49 were not. HLA-B27 was detected in 53.1% of patients in the sample. Patients with spondyloarthritis had lower heart rate (p=0.06), longer QT interval (p<0.0001) and higher prevalence of right bundle branch block (p=0.014) compared to controls. Duration of disease was weakly correlated with heart rate (Rho=0.26; 95%CI: 0.06-0.44; p=0.008). The prevalence of right bundle branch block was positively correlated with HLA-B27 positivity. Use of Anti-TNF-α drugs did not interfere with electrocardiographic parameters. CONCLUSION: Patients with spondyloarthritis had lower heart rate, longer QT interval and a higher prevalence of right bundle branch block compared to controls. HLA-B27 positivity was associated with the prevalence of right bundle branch block. Anti-TNF-α drugs had no impact on electrocardiographic findings.