Cost Effectiveness of Insulin Glargine versus Neutral Protamin Hagedorn Insulin in the Treatment of Type 2 Diabetes Patients in Turkey

Background: Type 2 diabetes mellitus (T2DM) poses a significant burden on population well being and healthcare expenditure in Turkey, with disease prevalence continuing to increase. Insulin treatment is necessary for patients failing to achieve glycaemic control with lifestyle modification or oral antidiabetic drugs. While neutral protamin Hagedorn (NPH) insulin has been traditionally prescribed for insulin introduction, insulin glargine has been shown to reduce glycated hemoglobin (HbA1c) with a more favourable hypoglycaemic profile. Objective: To evaluate the cost-effectiveness of insulin glargine compared to NPH insulin in patients with T2DM in Turkey, from a Social Security Institution perspective. Methods: A previously published discrete event simulation model of T2DM progression was utilised to characterise the cost-effectiveness of insulin glargine in a Turkish population given the benefits observed in clinical practice. Improvements in glycaemic control have been incorporated using data from The Health Improvement Network (THIN) database in the United Kingdom, combined with meta-regression results describing the relationship between hypoglycaemia and glycaemic control. Outcomes were evaluated over a 40-year horizon, and costs and benefits discounted at an annual rate of 3.5%. Results are reported in Turksih lira (TL), 2012. Results: Over a lifetime, the Incremental Cost-effectiveness Ratio (ICER) of insulin glargine compared to NPH was 40,101 TL per Quality-adjusted Life Year (QALY). Almost 52 hypoglycaemic events per patient were avoided with the use of insulin glargine compared to NPH, at an incremental lifetime cost of 7,140 TL per patient. The cost-effectiveness of insulin glargine is reduced when modelling only those benefits considered in the trial setting, while the cost-effectiveness profile can be expected to further improve in patients with higher HbA1c levels at baseline. Conclusion: It is difficult to interpret the results of modelling as there is no official cost-effectiveness threshold in Turkey. However, the results may be evaluated using thresholds derived according to methodology proposed by the World Health Organisation (WHO). Insulin glargine is expected to be costeffective compared to NPH insulin, with an ICER below three times the estimated gross domestic product (GDP) per capita; 56,850 TL.