Subjects and Methods
We studied 17 patients with type 2 diabetes who were hospitalized for
glycemic control at the Dokkyo Medical University Hospital (Mibu,
Tochigi, Japan). Patients were eligible for enrollment if they had type
2 diabetes, were at least 20 years old and had a glycated hemoglobin
(HbA1c) level of 6.0% to 12.0% on stable therapy with 1 to 3 oral
antidiabetic drugs with or without insulin for at least 3 months. During
hospitalization, all patients received an optimal diet therapy (25 to 30
kcal/kg of ideal body weight; 50% carbohydrate, 20% protein, and 30%
fat). Tofogliflozin 20 mg/day was administered to 10 patients who were
receiving DPP-4 inhibitors and to 7 patients who were not receiving
these drugs.
During the last week of hospitalization, a CGM device (iPro2; Medtronic
MiniMed. Inc., Northridge, CA, USA) was attached to each patient for 1
week. During the study period, no other anti-diabetic drugs were added
and the dose of antidiabetic drugs and insulin remained unchanged. The
starting day of CGM was defined as day 1. On day 4, treatment with
tofogliflozin 20 mg/day was started. We compared the mean values of CGM
parameters on day 2 and 3 (ie, before starting treatment with
tofogliflozin) with those on day 5 and 6 (ie, after staring treatment
with tofogliflozin). As indexes of glycemic variability, the 24-hour
mean glucose level, standard deviation (SD) of the 24-hour glucose
level, mean amplitude of glycemic excursions (MAGE), and mean of
postprandial glucose excursion (MPPGE) were calculated from CGM. We
evaluated postprandial glucose within 1 to 3 hours after each meal and
the time in range as the percent time with a glucose level between 70
and 180 mg/dL. Time below range was defined as the percent of time with
a glucose level less than 70 mg/dL, and time above range, as the percent
of time with a glucose level above 180 mg/dL.
All participants gave written informed consent to participate in the
study, which was approved by the Institutional Review Board of Dokkyo
Medical University (approval no. 28150). The study was registered with
the University Hospital Medical Information Network Clinical Trials
Registry (UMIN000025454).