classifying diabetes. This hope was reinforced by the discovery that the target for thiazolidinediones and sulfonylureas are risk loci for type 2 diabetes. Unfortunately, their effect on response to therapy is difficult to discern at an individual level and genotype at PPARG and KCNJ11 should not alter therapeutic choices in type 2 diabetes [57, 58].
Conclusions
Multiple roads lead to the pathophysiologic defects that cause hyperglycemia. While autoimmune diabetes can be characterized quite readily in many patients, the remaining patients are far more heterogeneous. Efforts to reinvent the classification, at least to date, have not appreciably changed, or guided, the management of individual patients – the notable exception being monogenic forms of diabetes. Nevertheless, appreciating the underlying defects as well as the limitations of autoantibody and β‐cell function testing should help improve the care of patients with unclear classification and with associated comorbidities.
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