Interleukin-6 blockade improves autonomic dysfunction in rheumatoid arthritis

Autonomic nervous system (ANS) involvement in rheumatoid arthritis (RA) is well recognised and contributes to arrhythmia and sudden death. However, there is no study documented the therapeutic efficacy on autonomic neuropathy (AN) in RA. This is the first reported observation of improvement in AN with interleukin-6 (IL-6) blockade with tocilizumab in RA. We report a case of 61-year old female with seropositive RA with severe disease activity, investigated for autonomic neuropathy. A battery of non invasive tests was used for accurate assessment of AN function based on assessment of peripheral sympathetic autonomic function and cardiovascular reflex tests. Tocilizumab 8 mg/kg intravenous infusion at weeks 0, 4 and 8 was added to her treatment regimen. Cardiovascular autonomic function tests at baseline showed marked abnormalities of parasympathetic cardiovascular reflexes. After the first dose of tocilizumab there was a rapid improvement with normalization of parasympathetic autonomic activity with subsequent doses. IL-6 blockade with tocilizumab seems to have the potential to improve the vagus nerve mediated parasympathetic neuropathy and hence has the potential to restore cholinergic anti-inflammatory pathway.