Cost-effectiveness analysis of combined antidiabetic therapy for type 2 diabetes mellitus in a tertiary health institution in north-central Nigeria

Abstract

Abstract 
Background: Anti-diabetic therapy is a lifetime treatment for patients suffering from diabetes mellitus. This 
translates into a substantial cost in drug therapy to patients who pay out of pocket, most especially in developing 
counties.As a result, it will be beneficial to identify competing options in drug therapy in order to redirect resources 
with the aim of achieving more in terms of cost-effectiveness. 
Objective:  to assess the cost-effectiveness of combined antidiabetic regimens in patients with type 2 diabetes 
mellitus (T2DM) in University of Ilorin, Teaching Hospital, Ilorin, Kwara state, North- central Nigeria. 
Method: A sample size of 276 casenotes from the total population was obtained after addition of a 5% attrition rate. 
A drug utilization study was then conducted through a one year retrospective review (January 2021 to December 
2021) of the276 case notesThe casenotes were selected by systematic random sampling using sampling interval of 5. 
This was accompanied by using the World Health Organization-defined daily dose method of evaluating drug use. 
TheEuroQoltool (EQ5D) was employed to evaluate the effectiveness of the identified treatment options in terms of 
quality adjusted life years (QALYs). 
Results:  
Combinations of Metformin/Glimepiride, Metformin/Linagliptin, and Metformin/Pioglitazone were 
identified anti-diabetic therapy options, with utilization patterns of 64.49%, 18.84%, and 16.67 %, respectively, and 
effectiveness of 0.755, 0.793, and 0.819 QALYs. 
Metformin/Linagliptin compared with Metformin/Glimepiride caused an incremental cost-effectiveness ratio ( 
ICER) of 823.16 USD/QALYs which is < GDP/capita of Nigeria ( $2, 097). Showing that Metformin/Linagliptin was 
more cost-effective. 
Metformin/ Pioglitazone was dominant when compared with Metformin/Glimepiride, giving an ICER of -25.78 
USD/QALYs, also showing that Metformin/ Pioglitazone was more cost effective. All ICERs achieved were robust to 
input parameter variation on sensitivity analysis.

Conclusion: Combinations of Metformin/Linagliptin and Metformin/Pioglitazone were both found to be more cost 
effective than Metformin/Glimepiride in the management of type 2 diabetes.