Type 2 diabetes: cost-effectiveness of medication adherence and lifestyle interventions

Tomaž Nerat, Igor Locatelli, Mitja Kos Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia Introduction: Type 2 diabetes is a major burden for the payer, however, with proper medication adherence, diet and exercise regime, complication occurrence rates, and consequently costs can be altered.Aims: The aim of this study was to conduct a cost-effectiveness analysis on real patient data and evaluate which medication adherence or lifestyle intervention is less cost demanding for the payer.Methods: Medline was searched systematically for published type 2 diabetes interventions regarding medication adherence and lifestyle in order to determine their efficacies, that were then used in the cost-effectiveness analysis. For cost-effectiveness analysis-required disease progression simulation, United Kingdom Prospective Diabetes Study Outcomes model 2.0 and Slovenian type 2 diabetes patient cohort were used. The intervention duration was set to 1, 2, 5, and 10 years. Complications and drug costs in euro (EUR) were based on previously published type 2 diabetes costs from the Health Care payer perspective in Slovenia.Results: Literature search proved the following interventions to be effective in type 2 diabetes patients: medication adherence, the Mediterranean diet, aerobic, resistance, and combined exercise. The long-term simulation resulted in no payer net savings. The model predicted following quality-adjusted life-years (QALY) gained and incremental costs for QALY gained (EUR/QALYg) after 10 years of intervention: high-efficacy medication adherence (0.245 QALY; 9,984 EUR/QALYg), combined exercise (0.119 QALY; 46,411 EUR/QALYg), low-efficacy medication adherence (0.075 QALY; 30,967 EUR/QALYg), aerobic exercise (0.069 QALY; 80,798 EUR/QALYg), the Mediterranean diet (0.057 QALY; 27,246 EUR/QALYg), and resistance exercise (0.050 QALY; 111,847 EUR/QALYg).Conclusion: The results suggest that medication adherence intervention is, regarding cost-effectiveness, superior to diet and exercise interventions from the payer perspective. However, the latter could also be utilized by patients without additional costs, but medication adherence intervention requires trained personnel because of its complex structure. Interventions should be performed for >2 years to produce noticeable health/cost results.Keywords: type 2 diabetes, adherence, intervention, medication, lifestyle, cost-effectivenes