Real-world GLP-1 RA therapy in type 2 diabetes: A long-term effectiveness observational study

Aims: To evaluate in a real-world setting the effectiveness and tolerability of available GLP-1 RA drugs in patients with type 2 diabetes after a prolonged follow-up. Materials and methods: Observational, retrospective, single-centre study in patients starting GLP-1 RA therapy. Change in HbA1c, fasting plasma glucose (FPG) and body mass index (BMI) along with gastrointestinal (GI) adverse events and withdrawal from GLP-1 RA therapy were evaluated. Lack of efficacy of GLP-1 RA therapy according to prespecified goals was also measured. Results: A total of 735 patients were included, mean age 59.7 years, duration of diabetes 9.01 years, HbA1c 8.18% and BMI 38.56 kg/m(2). Average follow-up was 18.97 months (range 4.2-39.09). All HbA1c (0.93%; P < 0.01), FPG (24 mg/dL; P < 0.01) and BMI (1.55 kg/m(2); P < 0.05) were significantly reduced from baseline and maintained throughout follow-up, regardless of prescribed GLP-1 RA. GI adverse events were present in 13.81% of patients at first follow-up visit, 37.07% of patients discontinued GLP-1 RA treatment, and 38.63% did not meet efficacy goals. Conclusions: In a real-world setting, GLP-1 RA therapy is largely prescribed in severely obese patients with a long-standing and poorly controlled diabetes. All prescribed GLP-1 RAs significantly decreased HbA1c, FPG and BMI. GI adverse events affected a low proportion of patients. Inversely, a high proportion of patients did not meet efficacy goals and/or discontinued GLP-1 RA treatment. Baseline characteristics of patients and lack of adherence may represent important issues underlying differences in effectiveness in real-world studies versus randomized trials.