Intensification of insulin therapy in patients with type 2 diabetes mellitus: an algorithm for basal-bolus therapy

Abstract

The incidence of diabetes mellitus is projected to continue to increase worldwide over the next 20 years leading to increased costs in the management of the disease and its associated co-morbidities. Insulin replacement is one of many treatment options that can help to bring about near normoglycemia in the patient with type 2 diabetes mellitus (T2DM). Glycemic control as close to normoglycemia as possible can help to reduce the risk of microvascular and macrovascular complications, yet less than one-half of patients with T2DM achieve glycemic targets as recommended by practice guidelines. The purpose of this review is to provide guidance to primary care physicians for the initiation and intensification of basal-bolus insulin therapy in patients with T2DM. Two treatment algorithms that can be both patient- and physician-driven are proposed: a stepwise approach and a multiple daily injections approach. Evidence shaping the two approaches will be discussed alongside management issues that surround the patient treated with insulin: hypoglycemia, weight gain, patient education, and quality of life.

Figure 1.

Insulin replacement regimens for the management of hyperglycemia. A: Once-daily, long-acting insulin analogue (black) or twice-daily, intermediate-acting human insulin (dashed) as basal replacement therapy. Insulin regimens can be intensified with the administration of a rapid-acting insulin analogue (light grey) at mealtimes in addition to long-acting (B) or intermediate-acting basal insulin (C). Arrows indicate insulin injections at mealtimes or bedtime. *As per the package insert, long-acting insulin glargine may be given at any time in the day, and insulin detemir once daily should be given in the evening. Adapted from De Witt et al. (21) with permission.

Figure 2.

Stepwise approach to the treatment of patients with type 2 diabetes mellitus. HbA_1C = glycosylated hemoglobin. Adapted from Raccah et al. (28) with permission.

Figure 3.

A stepwise method for the introduction of basal-bolus insulin therapy and bolus dose adjustment. *For a patient on < 40 units/day basal insulin, a starting dose of 3 units may be appropriate; ^†Dose corrections based on self-monitored blood glucose (SMBG) values at pre-meal (lunch and dinner) and bedtime; ^‡Glycemic targets: pre-meal SMBG of 5.0–7.2 mmol/L (90–130 mg/dL); bedtime SMBG of 6.1–7.8 mmol/L (110–140 mg/dL); targets should be individualized; ^§ADA 2012 recommends treating to HbA_1C < 7.0%; target should be individualized to the patient. FPG = fasting plasma glucose; HbA_1C = glycosylated hemoglobin.

Figure 4.

Dose adjustment for multiple daily injection insulin therapy.