Long term predictors of post-partum glucose metabolism in women with gestational diabetes mellitus.
OBJECTIVE
The question asked by this study was whether β-cell function expressed by insulin secretion/sensitivity measured during pregnancy in women with gestational diabetes (GDM) predicts post-partum long-term derangement in glucose metabolism.


METHODS
Seventy-four Caucasian women with previous GDM were retested through a 75 g-2-h-OGTT after 8 [6] years (median[interquartile range]) from index pregnancy, measuring at pregnancy and follow-up insulin sensitivity, insulin secretion (1-h-incremental-insulin-area/incremental-glucose-area: ΔAUC60 (I)/ΔAUC60 (G)) as well as the product of Stumvoll-first-phase - secretion x insulin sensitivity (insulin-secretion-sensitivity index (ISSI).


RESULTS
At follow-up 47 women were normotelerant to glucose and 27 had altered glucose metabolism (AGM:10 with type 2 diabetes and 17 with IGT). Women progressed to AGM had at their index pregnancy higher mean 2-h-OGTT-glucose area (1.15±0.09 VS. 1.09±0.09 mol l 2-h (-1);p=0.014), and lower ΔAUC60 (I)/ΔAUC60 (median [interquantile range]) (54.4 [51.7] vs. 73.4 [60] pmol mmol (-1)) and ISSI (2 977 [766] vs. 3 708 [1 141]; p<0.05 for both), but similar insulin sensitivity index 2.9 [2.5] VS. 3.2 [2.2] ml min (-1) m (-2);p=NS). Two-h-OGTT-glucose area, or decrease in ΔAUC60 (I)/ΔAUC60 (G) and ISSI were significantly associated with glucose tolerance impairment and with raised adjusted risk for AGM while insulin sensitivity at pregnancy did no predict AGM development.


CONCLUSIONS
In this group of women increased post-load plasma glucose and impaired β-cell function assessed during GDM pregnancy predict long-term post-partum AGM, while insulin sensitivity measured at the same time does not.
Seghieri
G
G
Department of Internal Medicine, Spedali Riuniti, Pistoia, Italy. gseghier@tin.it
Tesi
F
F
De Bellis
A
A
Anichini
R
R
Fabbri
G
G
Seghieri
M
M
Franconi
F
F
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D016640:Diabetes, Gestational / Q000378:metabolism*; D005260:Female; D005947:Glucose / Q000378:metabolism*; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood / Q000378:metabolism; D007333:Insulin Resistance; D000078790:Insulin Secretion; D049590:Postpartum Period / Q000097:blood / Q000378:metabolism*; D011247:Pregnancy
D001786:Blood Glucose; D007328:Insulin; D005947:Glucose