ABSTRACT
Diabetes is a major public health emergency of the 21st century. Results of the Indian Council of Medical Research-INdia DIABetes (ICMR-INDIAB) study have found prevalence of diabetes and prediabetes in India to be as high as 7.3% and 10.3%, respectively with nation-wide projection of 77.2 million people with prediabetes and 69.2 million with diabetes. It is well established that insulin resistance (IR) and islet ß-cell failure are the two major features of T2D Multiple mechanisms including glucotoxicity, lipotoxicity, oxidative stress, endoplasmic reticulum stress, formation of amyloid deposits in the islets, etc. have been hypothesized to participate in the pathology of the disease. In the concluding decade of the last century, numerous studies - prospective and cross-sectional, have confirmed the role of chronic low-grade inflammation as a pathogenetic factor of T2D. It has been shown that increased levels of various inflammatory markers and mediators including fundamental markers like white blood cell count, C-reactive protein (CRP) to the more specific circulating cytokines like, interleukin-6 (IL-6), IL-1ß, plasminogen activator inhibitor-1 (PAI-1), etc. correlate with incident T2D. Based on the robust evidence implying the role of inflammation in T2D pathogenesis, several studies have proven that the proinflammatory cytokines play a central role in the development of microvascular diabetic complications such as nephropathy, retinopathy, and neuropathy. Inflammation in T2D causes accelerated atherosclerosis which predisposes to CVD, the leading cause of mortality in these patients. Recently there is a considerable increase in the interest among the researchers about anti-inflammatory therapies in the setting of chronic disorders such as T2D and CV diseases. In a multi-country study conducted in Asia, approximately 50% of Indian respondents had poor diabetes control. Most patients initially respond to sulfonylurea and/or metformin, and later these agents lose their effectiveness with time. Therapeutic option in patients uncontrolled on two-drug combination therapy is either to add third oral drug or insulin. However, use of insulin is limited due to its high cost and poor compliance. Majority of new treatment options like GLP1 agonists, insulin analogs and SGLT2 inhibitors are costly considering they are still under patent. The thiazolidinedione class of drugs is associated with adverse effects like fluid retention and weight gain that may result in or exacerbate edema and congestive heart failure. Thus there is a need for a safe and inexpensive treatment option for the management of uncontrolled T2D. Considering the role of inflammation in T2D pathogenesis, the drug should not only have antihyperglycemic effects but also reduce inflammatory burden thus reducing the progression and complications of T2D. The current interest is apparently directed towards drugs targeting inflammation acting at different stages of the inflammatory cascade. In the recently published CANTOS study, canakinumab, a selective, high-affinity, fully human monoclonal antibody which inhibits IL-1ß, has no consistent long-term benefits on HbA1c. Other selective inhibitors like anakinra (IL-1 receptor antagonist) and etanercept (TNF inhibitor) too have yielded modest effects on glycemic parameters and insulin sensitivity. However, hydroxychloroquine (HCQ), a broad anti-inflammatory agent has been shown to reduce HbA1c by 0.87%. Hydroxychloroquine (HCQ) is considered as one of the safest disease modifying anti-rheumatic drug, used widely for the treatment of rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). The effect of HCQ in preventing development of diabetes in patients with chronic inflammatory diseases was highlighted in a prospective observational study of 4905 adults with rheumatoid arthritis and no diabetes with 21.5 years of follow-up. Patients who took HCQ for more than 4 years had a significant 77% lower risk of diabetes compared with non users of HCQ (RR, 0.23; 95% CI, 0.11-0.50). Taking cue from this study highlighting the anti-diabetic effect of HCQ, pioneering research studies evaluating these effects of HCQ were conducted in India. In 2014, hydroxychloroquine 400 mg got DCGI approval as an adjunct to diet and exercise to improve glycemic control of patients on metformin, sulfonylurea combination in Type 2 diabetes.
