Читать книгу Gestational Diabetes - Группа авторов - Страница 62

The IADPSG consensus panel acknowledged that the choice of thresholds for associations that are continuous and linear is arbitrary. The IADPSG recommended thresholds that are the average glucose values at which odds for birth weight above the 90th percentile, cord C-peptide above 90th percentile, and percent body fat above 90th percentile reached 1.75 times the estimated odds of these outcomes at mean glucose values [32]. The glucose values at a 1.75 OR are 5.1 (92 mg/dL), 10.0 (180 mg/dL), and 8.5 mmol/L (153 mg/dL) for FPG, 1-h, and 2-h OGTT plasma glucose concentrations, respectively. OR of 1.75 identifies 17.8% of the HAPO population as diabetic – 16.1% with one or more glucose values that meet or exceed the threshold and 1.7% of the cohort with overt diabetes. Accordingly, at this OR, adverse pregnancy outcome is increased, including preeclampsia (RR 2.02, p < 0.001), LGA (RR 1.95, p < 0.001), cord c-peptide (RR 2.62, p < 0.001), neonatal adiposity (RR 1.96, p < 0.001), preterm birth (RR 1.47, p < 0.001), shoulder dystocia or birth injury (RR 1.44, p < 0.01), and cesarean delivery (RR 1.45, p < 0.001).

The value of 1.75 is arbitrary and as such has been debated and questioned extensively in multiple aspects: increased prevalence, not easy to remember cutoffs, lack of evidence to support treatment, and more. Ryan et al. [35] concluded that an OR of a 1.75 would lead to GDM diagnosis in 4,150 women of the HAPO cohort (with 296 LGA babies), rather than in 2,448 women (with 181 LGA babies) if an OR of 2.0 would have been applied. The expected benefit in these 1,702 additional women would be the prevention of 140 cases of LGA, 21 cases of shoulder dystocia, and 16 cases of birth injury. At an OR of 2.0, the incidence of GDM in the HAPO cohort is reduced from 16.1 to 8.8%, meaning that the higher thresholds will not label many cases with GDM, while keeping a comparable risk of adverse outcomes.