Table 2.

Pharmacodynamic parameters following a mixed meal tolerance test on study day 1 (SD1, pre-treatment) and study day 2 (SD2, with metformin treatment) in non-pregnant control subjects with type 2 diabetes mellitus and women with gestational diabetes mellitus, corrected for gestational-age-dependent changes.

Parameter	GDM (n = 25)			T2DM (n = 12)
	SD1	SD2	Δ	SD1	SD2	Δ
SI (10−4 min−1 μU−1 mL)	3 ± 2	4 ± 2	2 ± 2 (0.5 to 3) (p=0.005)*	5 ± 8	6 ± 5	1 ± 5 (−2 to 4) (p=0.4)
Φtotal (10−9 min−1)	100 ± 50	130 ± 70	30 ± 60 (1 to 50) (p=0.04)*	30 ± 30	40 ± 30	10 ± 20 (−0.4 to 30) (p=0.06)
Φstatic (10−9 min−1)	90 ± 40	120 ± 70	30 ± 60 (1 to 50) (p=0.04)*	30 ± 30	40 ± 30	10 ± 20 (−0.6 to 30) (p=0.06)
Φdynamic (10−9)	2,000 ± 1,000	2,000 ± 1,000	100 ± 1,000 (−300 to 600) (p=0.5)	600 ± 900	600 ± 700	50 ± 700 (−400 to 500) (p=0.8)
Φbaseline (10−9 min−1)	11 ± 5	9 ± 6	−3 ± 4 (−4 to −0.9) (p=0.004)*	6 ± 4	7 ± 4	1 ± 2 (−0.3 to 2) (p=0.1)
DI (10−13 min−2 μU−1 mL)	300 ± 300	600 ± 400	300 ± 500 (100 to 500) (p=0.003)*	200 ± 300	200 ± 200	40 ± 100 (−50 to 100) (p=0.4)
MMTT Peak glucose (mg/dL)	150 ± 20	140 ± 20	−10 ± 20 (−20 to −4) (p=0.006)*	280 ± 80	220 ± 80	−60 ± 90 (−100 to −4) (p=0.04)*

GDM = gestational diabetes mellitus group, T2DM = type 2 diabetes mellitus group, SD = study day, Δ = average change between SD1 and SD2, SI = insulin sensitivity, Φ = β-cell responsivity, DI = disposition index, MMTT = mixed-meal tolerance test. Results reported as mean ± standard deviation (95% confidence interval).

^*Statistically different comparing SD2 to SD1.