Insulin initiation in patients with type 2 diabetes mellitus: treatment guidelines, clinical evidence and patterns of use of basal vs premixed insulin analogues

This review addresses the apparent disconnect between international guideline recommendations, real-life clinical practice and the results of clinical trials, with regard to the initiation of insulin using basal (long-acting) or premixed insulin analogues in patients with type 2 diabetes (T2D). English language guidelines vary considerably with respect to recommended glycaemic targets, the selection of human vs analogue insulin, and choice of insulin regimen. Randomised trials directly comparing insulin initiation between basal and premixed analogues are scarce, and hard endpoint outcome data are inadequate. The evidence presented suggests that a major component of the HbA1c not being attained in every day clinical practice may be a result of factors that are not adequately addressed in forced titration trials of highly motivated patients, including failure to comply with complex treatment and monitoring regimens. Enforced intensification of unrealistic complex treatment regimens and glycaemic targets may theoretically worsen the psychological well-being in some patients. More simple and sustainable treatment regimens and guidelines are urgently needed. As for the use of insulin in T2D, there is limited evidence to convincingly support that initiation of insulin using basal insulin analogues is superior to initiation using premixed insulin analogues. While awaiting improved clinical efficacy and cost-effectiveness data, practical guidance from national and international diabetes organisations should consider more carefully the importance of: i) being clear and consistent; and ii) the early implementation of sustainable and cost-effective insulin treatment regimens with an emphasis on optimising treatment ease of use and patient compliance.