Abstract
INTRODUCTION: Treatment-related quality of life (QOL) is an important aspect of diabetes management. We evaluated the influence of a sodium-glucose cotransporter 2 (SGLT2) inhibitor, tofogliflozin, on treatment-related QOL in Japanese patients with type 2 diabetes mellitus (T2DM). METHODS: This is the prespecified subanalysis study of the "Using TOfogliflozin for Possible better Intervention against Atherosclerosis for type 2 diabetes patients (UTOPIA)" trial. Treatment-related QOL was evaluated at baseline, week 26, week 52, and week 104 after the initiation of the study using the Diabetes Therapy-Related QOL questionnaire (DTR-QOL). Among the 340 patients in the original UTOPIA study, a total of 252 patients (127, tofogliflozin group; 125, conventional treatment group) who completed the DTR-QOL questionnaire at baseline were the study subjects of the current subanalysis. RESULTS: The tofogliflozin and conventional treatment groups exhibited almost comparable baseline clinical characteristics, while the use of antihypertensive drugs and lipid-lowering agents was significantly lower in the tofogliflozin treatment group than in the conventional treatment group. Tofogliflozin treatment increased the total score of DTR-QOL7 from baseline (P < 0.001), while conventional treatment did not change it. There were statistically significant differences in delta change in the total DTR-QOL7 score and DTR-QOL7 Q4, Q5, Q6, and Q7 scores from the baseline to week 104 between the treatment groups. Delta changes in HbA1c (Spearman's correlation coefficient, ρ = - 0.30, P < 0.001), fasting blood glucose (ρ = - 0.16, P = 0.031), BMI (ρ = - 0.19, P = 0.008), and waist circumference (ρ = - 0.17, P = 0.024) at week 104 were negatively associated with delta change in the total QOL7 score. CONCLUSIONS: Our data indicated that tofogliflozin treatment improved treatment-related QOL compared to conventional treatment in Japanese patients with T2DM, in accordance with the improvement of major cardiovascular risk factors. TRIAL REGISTRATION: UMIN000017607.