Cardiac autonomic modulation in juvenile idiopathic arthritis with use of biological medication: case report

Introduction: The introduction of biological medication in Juvenile Idiopathic Arthritis (JIA) proposes better therapeutic results with decreased pain and inflammation and consequent reduction in joint damage. The autonomic state can be a predictor for verifying the response to immunomodulation therapy. Thus, measuring heart rate variability can express autonomous behavior and possibly accompany the response to therapy through the expression of the inflammatory condition. Objective: Analysis of heart rate variability in a child with Juvenile Idiopathic Arthritis using the anti-Tumor Necrosis Factor. Methods: This is a clinical case report of an 8-year-old male with a diagnosis of JIA - oligoarticular form, using etanercept, admitted to Clínica Escola de Fisioterapia UNINORTE, Acre, Brazil in 2017. We analyzed laboratory and imaging tests, kinetic-functional evaluation, examination of cardiac autonomic modulation and physiotherapeutic treatment for analgesic, anti-inflammatory purposes, gaining flexibility, strength and postural re-education, according to CARE guidelines, case report guidelines. Results: After medication administration, there was a decrease in pain and normalization of serum creatinine (0.50 mg / dL) and CRP (less than 6 mg / dL) and an increase in erythrocyte sedimentation rate (17 mm3). In the examination of heart rate variability, the linear indices in the time domain showed a predominance of parasympathetic activity (RMSSD: 35ms), with decreased sympathetic control measured through the frequency domain (LF: 27.1 un). However, non-linear methods showed low variability with little dispersion of RR intervals. Conclusion: In the present report, the linear indices showed parasympathetic predominance and in the non-linear analysis a low heart rate variability with abnormal and insufficient adaptation of the autonomic nervous system in a child with juvenile idiopathic arthritis using biological medication.