Glycemic Variability in Early Pregnancy May Predict a Subsequent Diagnosis of Gestational Diabetes

Figures & data

Figure 1 Flow chart of study participants.

Table 1 Baseline Characteristics of the 60 Pregnant Study Participants with GDM and Without GDM Outcomes

Maternal Characteristics (n=60)*	GDM (n=10)	Non-GDM (n=50)	p
Ethnicity, n (%)			0.62
Chinese	7 (70.0)	30 (60.0)
Malay	2 (20.0)	17 (34.0)
Indian	0 (0)	1 (2.0)
Others	1 (10.0)	2 (4.0)
Education, n (%)			0.91
Secondary and below	1 (10)	5 (11.1)
College and above	9 (90)	40 (88.9)
Family history of diabetes, n (%)	6 (60.0)	21 (42.0)	0.33
History of Gestational diabetes mellitus, n (%)	0 (0.00)	0 (0.00)	1.00
Parity, n (%)	4 (40.0)	31 (62.0)	0.22
Age (years), mean ± SD	30.6±4.4	30.6±3.9	0.96
%Pre-pregnancy BMI (kg/m^2), mean ± SD	28.1±7.4	23.9±5.4	0.04
Mean gestational age of GDM diagnosis (weeks), mean ± SD	26.4±1.7	–	–
FPG from OGTT (mmol/L), mean ± SD	5.58±2.2	4.30±0.3	0.10
1 h glucose (mmol/L), mean ± SD	11.2±3.6	7.21 ±1.2	0.006
2 h glucose (mmol/L), mean ± SD	8.12±3.3	6.05±1.2	0.08
Mean CGM wear-time (days), mean ± SD	13.5±1.5	13.7±0.8	0.67

Notes: The p value significance is set at p<0.05. *Missing data: Education (n=5); pre-pregnancy BMI (n=1).

Abbreviations: FPG, fasting plasma glucose; GDM, gestational diabetes mellitus; BMI, body mass index; OGTT, oral glucose tolerance test.

Table 2 Glycemic Variability in the 1st Trimester in Pregnant Women with and without GDM (n=60)

CGM Parameters (n=60)	GDM (n=10) Adjusted Median (IQR)	Non-GDM (n=50) Adjusted Median (IQR)	Adjusted p*
First trimester
Gestational age at CGM application (weeks), mean ± SD	11.1±1.2	11.1±1.4	0.93
Mean glucose (mmol/L)	4.43 (4.2–4.6)	4.07 (4.0–4.2)	0.20
J-Index	10.0 (8.8–10.4)	8.26 (7.1–9.8)	0.04
MAGE (mmol/L)	3.26 (3.2–3.3)	2.59 (2.4–2.6)	0.002
SD (mmol/L)	1.31 (1.27–1.32)	1.01 (0.95–1.02)	0.001
CV (%), adjusted mean ± SD	28.3±1.6	24.3±1.1	0.007
TIR (%), adjusted mean ± SD	68.9±5.4	69.2±3.9	0.51
TBR (%), adjusted mean ± SD	26.9±5.7	30.3±4.2	0.84
TAR (%)	4.30 (3.96–4.40)	0.59 (0.20–0.93)	0.05

Notes: *p values were adjusted for maternal pre-pregnancy BMI and ethnicity Data was expressed as adjusted median (interquartile range) unless otherwise stated. The p value significance is set at p<0.003.

Abbreviations: GDM, gestational diabetes mellitus; BMI, body mass index; CGM, continuous glucose monitoring; %CV, coefficient of variation; SD, standard deviation; MAGE, Mean amplitude of glycemic excursions; GA, gestational age; %TAR, percentage of time above target range; %TIR, percentage of time in range; %TBR, percentage of time below target range.

Table 3 Glycemic Variability in the 2nd Trimester in Pregnant Women with and without GDM (n=53)

CGM Parameters (n=53)	GDM (n=9) Adjusted Median (IQR)	Non-GDM (n=44) Adjusted Median (IQR)	Adjusted p*
Second trimester
Gestational age at CGM application (weeks), mean ± SD	20.6±1.2	20.5±0.90	0.99
Mean glucose (mmol/L)	4.88 (4.8–5.1)	4.09 (4.0–4.2)	0.02
J-Index	13.5 (12.9–14.7)	8.50 (8.1–9.2)	0.007
MAGE (mmol/L)	3.32 (3.3–3.4)	2.42 (2.4–2.5)	<0.001
SD (mmol/L)	1.35 (1.3–1.4)	0.99 (0.98–1.01)	0.003
CV (%), adjusted mean ± SD	27.5±2.4	24.4±1.7	0.13
TIR (%), adjusted mean ± SD	72.3±2.1	68.7±1.5	0.74
TBR (%), adjusted mean ± SD	19.8±4.4	30.5±3.2	0.35
TAR (%)	7.42 (6.4–9.4)	0.33 (−0.03–1.7)	0.07

Notes: Data was expressed as adjusted median (interquartile range) unless otherwise stated. The p value significance level is set at p<0.003. *p values were adjusted for maternal pre-pregnancy BMI and ethnicity.

Abbreviations: GDM, gestational diabetes mellitus; BMI, body mass index; CGM, continuous glucose monitoring; %CV, coefficient of variation; SD, standard deviation; MAGE, Mean amplitude of glycemic excursions; GA, gestational age; %TAR, percentage of time above target range; %TIR, percentage of time in range; %TBR, percentage of time below target range.