Patient preferences for treatment in type 2 diabetes: the Italian discrete-choice experiment analysis

Aims: Several drug classes are now available to achieve a satisfactory metabolic control in patients with type 2 diabetes (T2DM), but patients’ preferences may differ. Methods: In a discrete-choice experiment, we tested T2DM patients’ preferences for recent antidiabetic drugs, in the event that their treatment might require intensification. The following attributes were considered: (a) route of administration; (b) type of delivery; (c) timing; (d) risk of adverse events; (e) effects on body weight. Twenty-two possible scenarios were built, transferred into 192 paired choices and proposed to 491 cases naïve to injectable treatments and 171 treated by GLP-1 receptor agonists (GLP-1RAs). Analyses were performed by descriptive statistics and random effects logit regression model. Results: Preferences according to dosing frequency, risk of nausea and urinary tract infections (UTls) were similar across groups, age, sex and BMI. Administration route and delivery type accounted for 1/3 of relative importance; the risk of UTIs, nausea and dosing frequency for ≈ 20% each, and weight loss for only 6%. Two significant interactions emerged (p < 0.01): type of delivery × group, and weight change × BMI class. Irrespective of previous treatment, the three preferred choices were injectable, coupled with weekly dosing and a ready-to-use device (first two choices). In a regression model, being naïve or non-naïve changed the ranking of preferences (p < 0.001), and the order was systematically shifted towards injectable medications in non-naïve subjects. Conclusion: Easy-to-deliver, injectable treatment is preferred in T2DM, independently of treatment history, and previous experience with GLP-1RAs strengthens patients’ willingness to accept injectable drugs.