Diabetes mellitus in rheumatic diseases: clinical characteristics and treatment considerations

New pathophysiological insights are now available on comorbidities in rheumatic diseases (RDs). Several nationwide studies point to the fact that comorbid diabetes mellitus (DM) increases the risk of adverse outcomes in patients with various RDs. Genetic factors, intensity of systemic inflammation, anti-inflammatory potential of therapeutic agents, and duration of RDs have been insufficiently explored in the context of comorbidities. Some disease-modifying antirheumatic drugs (DMARDs) have demonstrated a potential to improve the glycemic control while glucocorticoids (GCs) have worsened it, particularly in systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Anti-TNFalpha agents in combination with hydroxychloroquine (HCQ) have been associated with a reduced risk of DM in patients with RA, ankylosing spondylitis (AS), Sjögren syndrome (SS), and SLE. Better understanding of confounding factor of currently available antirheumatic therapies in patients with DM and RDs will pave the way for a tailored approach, limiting the severity of clinical manifestations and reducing the mortality risk.