Recent Updates to Clinical Practice Guidelines for Diabetes Mellitus

Abstract

Guidelines for the management of patients with diabetes have become an important part of clinical practice that improve the quality of care and help establish evidence-based medicine in this field. With rapidly accumulating evidence on various aspects of diabetes care, including landmark clinical trials of treatment agents and newer technologies, timely updates of the guidelines capture the most current state of the field and present a consensus. As a leading academic society, the Korean Diabetes Association publishes practice guidelines biennially and the American Diabetes Association does so annually. In this review, we summarize the key changes suggested in the most recent guidelines. Some of the important updates include treatment algorithms emphasizing comorbid conditions such as atherosclerotic cardiovascular disease, heart failure, and chronic kidney disease in the selection of anti-diabetic agents; wider application of continuous glucose monitoring (CGM), insulin pump technologies and indices derived from CGM such as time in range; more active screening of subjects at high-risk of diabetes; and more detailed individualization in diabetes care. Although there are both similarities and differences among guidelines and some uncertainty remains, these updates provide a good approach for many clinical practitioners who are battling with diabetes.

Keywords: Blood glucose; Consensus; Diabetes mellitus, type 2; Evidence-based medicine.

Fig. 1

Treatment algorithm 1 (initial therapy) for patients with type 2 diabetes mellitus (T2DM). The algorithm stratifies the strategy of glycemic control for T2DM based on initial glycosylated hemoglobin (A1C) levels and underlying comorbidities. For newly diagnosed T2DM, begin with comprehensive lifestyle modification (LSM) at the time of diagnosis and monitor continuously. If the initial severe hyperglycemia (A1C level ≥9.0%) is accompanied by symptoms of hyperglycemia, insulin treatment should be prioritized (algorithm 3). If heart failure (HF), established atherosclerotic cardiovascular disease (eASCVD), or chronic kidney disease (CKD) are present, follow algorithm 4. If glycemic target is not achieved within 3 months after LSM, then glucose-lowering agent should be initiated promptly. If the current A1C is 1.5% higher than that of the target A1C or the current A1C level is ≥7.5%, follow algorithm 2 (combination therapy). If the A1C level is 7.5% or less, metformin monotherapy is recommended as a first-line therapy. However, if there are contraindications or intolerable side effects related to metformin use, a different class of medications can be considered. Instead of metformin monotherapy, early combination therapy could be considered to reduce the risk of failure of glycemic control in some patients with newly diagnosed T2DM. Reprinted from Hur et al. [1]. ^aParticularly HF with reduced ejection fraction (HFrEF, clinical diagnosis of HF and left ventricular ejection fraction ≤40%); ^bA history of an acute coronary syndrome or myocardial infarction, stable or unstable angina, coronary heart disease with or without revascularization, other arterial revascularization, stroke, or peripheral artery disease assumed to be atherosclerotic in origin; ^cestimated glomerular filtration rate <60 mL/min/1.73 m² or urine albumin creatinine ratio ≥30 mg/g.

Fig. 2

A framework for the follow-up treatment of an individual with type 1 diabetes. Modified from Holt et al. [53]. CGM, continuous glucose monitoring.