Effects of Metformin Added to Insulin in Adolescents with Type 1 Diabetes: An Exploratory Crossover Randomized Trial

Table 1

Baseline characteristics of the randomized participants.

Characteristic	Overall	Sequence A†	Sequence B†	value
Number of subjects ()	17	9	8
Female, (%)	7 (41.18)	3(33.33)	4 (50)	0.64
Age (years)				0.09
Duration of diabetes (years)	4.50 (3.58, 6.92)	4.67 (4, 10.5)	3.96 (3.04, 5.88)	0.34
Tanner stage‡	4 (2-5)	4 (2-5)	3 (2-4)	0.24
BMI (kg/m^2)				0.85
Systolic BP (mmHg)				0.29
Diastolic BP (mmHg)				0.39
Insulin dose (units/kg/day)	0.94 (0.89, 1.02)	0.96 (0.91, 1.02)	0.92 (0.85, 1.06)	0.85
Lipid profiles
TC (mmol/L)				0.97
LDL-C (mmol/L)	2.53 (2.13, 3.25)	2.24 (2.13, 3.26)	2.58 (2.13, 2.99)	0.92
HDL-C (mmol/L)				0.34
TG (mmol/L)	0.61 (0.51, 0.76)	0.52 (0.47, 0.61)	0.73 (0.61, 0.82)	0.03
Fasting glucose (mmol/L)				0.54
HbA1c (%)	9.0 (8.5, 9.4)	8.7 (8.4, 9.1)	9.3 (8.7, 9.6)	0.18
Insulin sensitivity index (lnIS)§				0.32
CGM parameters
	16	9	7
MBG (mmol/L)				0.56
%CV				0.62
MAGE (mmol/L)				0.37
MODD (mmol/L)				0.20
Holter parameters
	15	8	7
SDNN (ms)				0.37
SDANN (ms)				0.41
RMSSD (ms)				0.50
PNN50 (%)				0.92
LogLF (ms^2)				0.55
LogHF (ms^2)				0.56
LF/HF				0.66

Data are (SD), median (interquartile range (IQR)), or counts (percentage) unless otherwise noted. †Sequence A, metformin nonmetformin; sequence B, nonmetformin metformin. ‡Tanner stage was presented as median (range). § (mg/dL, to convert TG values from mmol/L to mg/dL, divide by 0.0113). BMI: body mass index; BP: blood pressure; TC: total cholesterol; LDL-C: low-density lipoprotein cholesterol; HDL-C: high-density lipoprotein cholesterol; TG: triglyceride; CGM: continuous glucose monitoring; MBG: mean blood glucose; %CV: coefficient of variability of glycemia; MAGE: mean amplitude of glycemic excursions; MODD: means of daily differences; HRV: heart rate variability; SDNN: standard deviation of all RR intervals; SDANN: standard deviation of all the 5-minute RR intervals; RMSSD: square root of the mean of the sum of squares of differences between adjacent RR intervals; PNN50: the percentage of the interval differences of successive RR intervals greater than 50 ms; LF: low frequency; HF: high frequency; LF/HF: low frequency/high frequency.