SCREENING FOR TYPE 2 DIABETES

Speculate to Accumulate - Screening for Type 2 Diabetes, is it really cost effective?

Screening for Type 2 Diabetes, is it really cost effective?

Introduction

It is well known that tight glycaemic control decreases the risk of long-term complications such as retinopathy, nephropathy, neuropathy and cardiovascular disease in patients with type 1 or type 2 diabetes [1], [2] and [3]. In order to achieve optimal glycaemic control, insulin is recommended in patients with type 2 diabetes who fail to maintain near-normal HbA1c levels (<7.0%) after good adherence to an oral antidiabetic drug (OAD), generally metformin, in addition to diet and exercise control [4] and [5]. In light of the projected near-doubling of the number of individuals with diabetes over the next 25 years [6], and the associated increase in direct expenditure of $223 million (in 2007 USD), the costs of treating this population merit close scrutiny.

The long-acting insulin analogues (LAIAs) insulin glargine and insulin detemir have broadened the treatment choices for patients with diabetes, offering therapeutic efficacy at least equivalent to that provided by conventional human basal insulin (neutral protamine Hagedorn insulin [NPH]) but with a lower risk of hypoglycaemia; in the case of insulin detemir, there is also the advantage of less weight gain [7], [8], [9], [10], [11] and [12]. Compared to NPH insulin, the addition of insulin detemir [13] and [14] or insulin glargine [15] and [16] to OADs in conventional or treat-to-target studies has shown similar reductions in HbA1c (approximately 1.6-1.8%) and fasting glucose (approximately 2.8-4.2 mmol/L), and allowed a similar proportion of patients (60-70%) to reach HbA1c =7%. However, as documented in the recent consensus statement from the American Association of Clinical Endocrinologists and American College of Endocrinology [17], and in guidelines published by the National Institute for Clinical Excellence in the United Kingdom [18], basal insulin analogues are associated with a significantly lower rate of hypoglycaemic events than NPH insulin, reflecting their prolonged duration of action with minimal peak effect, as well as greater consistency in blood and plasma glucose concentrations [5]. Previous studies have demonstrated that the higher acquisition costs of LAIAs compared with conventional human basal insulin are more than offset by the cost savings that result from reduced hypoglycaemia and fewer long-term complications [12].

Comparisons between insulin detemir and glargine generally find equivalent glycaemic control and similar rates of hypoglycaemia, although insulin detemir is typically associated with less weight gain [8], [10] and [12]. These properties have also been documented in real-life settings. For example, a retrospective cohort analysis of data from a large US managed care organisation analysed the degree of glycaemic control and weight change achieved by poorly controlled (<12% of patients had HbA1c <7%), insulin-naïve patients initiated on human or analogue insulin in an ambulatory care setting. The study showed no difference in HbA1c outcomes between insulin classes (p < 0.05). Patients using insulin detemir were 30% less likely to gain weight (=0.9 kg) than glargine users (p < 0.05). Thus, weight outcomes for basal analogue insulin may differ ...