title: Cost-effectiveness of dipeptidyl peptidase-4 inhibitor monotherapy in elderly type 2 diabetes patients in Thailand.
abstract: BACKGROUND
  The management of type 2 diabetes mellitus (T2DM) in elderly population poses many challenges. Dipeptidyl peptidase-4 (DPP-4) inhibitors show particular promise due to excellent tolerability profiles, low risk of hypoglycemia, and little effect on body weight. This study evaluated, from the health care system's perspective, the long-term cost-effectiveness of DPP-4 inhibitor monotherapy vs metformin and sulfonylurea (SFU) monotherapy in Thai elderly T2DM patients.
  
  
  METHODS
  The clinical efficacy was estimated from a systematic review and meta-analysis. Baseline cohort characteristics and cost parameters were obtained from published studies and hospital databases in Thailand. A validated IMS CORE Diabetes Model version 8.5 was used to project clinical and economic outcomes over a lifetime horizon using a 3% annual discount rate. Costs were expressed in 2014 Thai Baht (THB) (US dollar value). Incremental cost-effectiveness ratios were calculated. Base-case assumptions were assessed through several sensitivity analyses.
  
  
  RESULTS
  For treating elderly T2DM patients, DPP-4 inhibitors were more expensive and less effective, ie, a dominated strategy, than the metformin monotherapy. Compared with SFU, treatment with DPP-4 inhibitors gained 0.031 more quality-adjusted life years (QALYs) at a total cost incurred over THB113,701 or US$3,449.67, resulting in an incremental cost-effectiveness ratio of THB3.63 million or US$110,133.50 per QALY. At the acceptable Thai ceiling threshold of THB160,000/QALY (US$4,854.37/QALY), DPP-4 inhibitors were not a cost-effective treatment.
  
  
  CONCLUSIONS
  DPP-4 inhibitor monotherapy is not a cost-effective treatment for elderly T2DM patients compared with metformin monotherapy and SFU monotherapy, given current resource constraints in Thailand.
authors.affiliation: Faculty of Pharmacy Chiang Mai University, Chiang Mai.
authors.forename: Unchalee
authors.initials: U
authors.lastname: Permsuwan
authors.affiliation: Center of Pharmaceutical Outcomes Research, Faculty of Pharmaceutical Sciences, Naresuan University, Phitsanulok.
authors.forename: Piyameth
authors.initials: P
authors.lastname: Dilokthornsakul
authors.affiliation: Center of Pharmaceutical Outcomes Research, Faculty of Pharmaceutical Sciences, Naresuan University, Phitsanulok; Center of Health Outcomes Research and Therapeutic Safety, School of Pharmaceutical Sciences, University of Phayao, Phayao, Thailand; School of Pharmacy, Monash University Malaysia, Sunway, Malaysia.
authors.forename: Surasak
authors.initials: S
authors.lastname: Saokaew
authors.affiliation: Ottawa Hospital Research Institute, The Ottawa Hospital; School of Epidemiology, Public Health and Preventive Medicine, Faculty of Medicine, University of Ottawa, Ottawa; Institute for Clinical and Evaluative Sciences, Toronto, ON, Canada.
authors.forename: Kednapa
authors.initials: K
authors.lastname: Thavorn
authors.affiliation: Center of Pharmaceutical Outcomes Research, Faculty of Pharmaceutical Sciences, Naresuan University, Phitsanulok; School of Pharmacy, Monash University Malaysia, Sunway, Malaysia; School of Population Health, The University of Queensland, Brisbane, QLD, Australia; School of Pharmacy, University of Wisconsin-Madison, Madison, WI, USA.
authors.forename: Nathorn
authors.initials: N
authors.lastname: Chaiyakunapruk
keywords: DPP-4 inhibitor; Thailand; cost-effectiveness analysis; elderly; type 2 diabetes