Giving Insulin Is Not a Guessing Game: Insulin Replacement Therapy in Type 2 Diabetes Mellitus

Abstract

In 2021, 537 million adults were living with diabetes. Being a progressive disease, there would eventually be failure of oral hypoglycemic agents (OHA) to maintain good glycemic control and a majority will require insulin. However, optimal glycemic control has not been satisfactory in a significant proportion of patients who were on insulin therapy. Patient factors (eg, awareness, compliance, socioeconomic) have been identified but physician-related factors are as important. These include incorrect choice and inappropriate combination of insulin therapy which could be corrected by making the treatment physiologic. The purpose of this article is to improve management decisions in type 2 diabetes by reviewing its pathophysiology and identifying the optimum insulin regimen that could mimic such. Since eventual beta cell failure is central to its pathophysiology, it is but reasonable to replace insulin by mimicking its physiologic secretion. Hence, the term Insulin Replacement Therapy (IRT) should be utilized. This could be provided by the combination of premix insulin (ie, NPH + regular insulin) and rapid-acting insulin which has been reported to provide an initial 17.5% HbA1c reduction and even 18% reduction on 5-year follow-up providing sustainable control. A stepwise approach is an effective tool for insulin intensification. Hypoglycemia in insulin therapy could be prevented with an appropriate dietary regimen through automatic snacking. Keywords: Insulin replacement therapy, type 2 diabetes mellitus, pathophysiology