Pharmacological Management of Diabetes for Reducing Glucose Levels and Cardiovascular Disease Risk: What Evidence in South Asians?

INTRODUCTION: South Asians experience more type 2 diabetes, which is earlier in onset and with more rapid glycaemic deterioration, although average body mass indices are lower than in whites. Cardiovascular outcomes from diabetes drug trials are now reported as standard, with data from newer therapies influencing patient management. However, less is known of the effect of such therapies in South Asians. The aim of this narrative review was to extract, wherever possible, the glucose-lowering efficacy and cardiovascular and renal outcome data for these therapies in South Asians. DISCUSSION: Despite the higher prevalence and global burden of type 2 diabetes and adverse outcomes in South Asians, they remain underrepresented in global trials. Even when recruited, the current method of classifying ethnicity does not commonly allow South Asian data to be extracted and reported separately from all Asians. Interrogation of available trial data suggests broadly comparable effects on glycaemia and weight in Asians to other ethnicities with use of glucagon-like peptide 1 receptor agonists (GLP-1 RAs), but a potentially early, albeit marginally, greater glycaemia benefit with Dipeptidyl peptidase-4 inhibitors (DPP4is) which may not be sustained. Furthermore, there appears a potentially greater glycaemia benefit with use of sodium-glucose transport protein 2 inhibitors (SGLT2is) in Asians compared to whites. Whether such findings are true in all Asians subgroups requires further direct study. For cardiovascular outcomes, available data suggest at least comparable and potentially greater outcome benefits in Asians; point estimates were more favourable for Asians in the vast majority of GLP-1 RAs and SGLT2is outcome trials. It was, however, impossible to determine whether the effects were similar across all Asian subgroups. CONCLUSION: We conclude that trialists should be encouraged to record ethnicity with better granularity to allow differing ethnic groups data to be better interrogated. In the meantime, doctors should, where possible, confidently follow newer guidelines for the use of newer glucose lowering agents for treating glycaemia and for the prevention of cardiovascular and cardiorenal complications in South Asian people with type 2 diabetes.