Defining criteria for the introduction of liraglutide using the glucagon stimulation test in patients with type 2 diabetes.
OBJECTIVE
To define a set of criteria using indices of β-cell function, including results from the glucagon stimulation test, for liraglutide introduction in patients with type 2 diabetes.


METHODS
In the present retrospective cohort study, patients were included in our analysis if their β-cell function had been evaluated with a glucagon stimulation test and a 24-h urinary C-peptide (U-CPR) excretion test before switching from insulin therapy to liraglutide monotherapy. The efficacy of liraglutide was determined by the extent to which glycemic control was achieved or if glycated hemoglobin levels were maintained at <7.0% after liraglutide monotherapy for 24 weeks.


RESULTS
Liraglutide was effective in 36 of 77 patients. In the liraglutide-effective cases, the following parameters were higher: fasting C-peptide (CPR0) levels, C-peptide levels 6 min after glucagon stimulation (CPR6), the C-peptide index (CPI; CPR0 × 100/fasting plasma glucose) and stimulated C-peptide index (S-CPI; CPR6 × 100/plasma glucose 6 min after glucagon stimulation). U-CPR did not differ between liraglutide-effective and liraglutide-ineffective cases. Using receiver operating characteristic analysis adjusted for baseline characteristics, the independent cut-off value for effective liraglutide introduction was 0.72 for CPI and 1.92 for S-CPI.


CONCLUSIONS
Evaluation of β-cell function using the glucagon stimulation test is useful for determining the efficacy of liraglutide introduction in patients with type 2 diabetes.
Department of Endocrinology and Metabolism Chigasaki Municipal Hospital Chigasaki Kanagawa Japan ; Department of Endocrinology and Metabolism Graduate School of Medicine Yokohama-City University Yokohama Japan.
Yoshinobu
Y
Kondo
Department of Endocrinology and Metabolism Chigasaki Municipal Hospital Chigasaki Kanagawa Japan.
Shinobu
S
Satoh
Department of Endocrinology and Metabolism Chigasaki Municipal Hospital Chigasaki Kanagawa Japan.
Joe
J
Nagakura
Department of Endocrinology and Metabolism Chigasaki Municipal Hospital Chigasaki Kanagawa Japan.
Masayo
M
Kimura
Department of Clinical Pharmacology and Therapeutics Graduate School of Medicine University of the Ryukyus Okinawa Japan.
Uru
U
Nezu
Department of Endocrinology and Metabolism Graduate School of Medicine Yokohama-City University Yokohama Japan.
Yasuo
Y
Terauchi
Glucagon stimulation test; Liraglutide; Type 2 diabetes