Re: Gestational diabetes: new criteria may triple the prevalence but effect on outcomes is unclear
The recent analysis of gestational diabetes (GDM) (BMJ 2014:348:g1567) summarises the on-going debate about whether to screen for and indeed treat gestational diabetes. The authors conclude that mild glycaemia ‘does not carry anything like the same degree of risk’ (as pre-existing type 1 or 2 diabetes) and imply that treating GDM is without clear evidence of clinically important benefit.
Two randomized controlled trials (mentioned, but not given much credit in the article) have established the clinical benefit of treating gestational diabetes. Crowther et al. showed that treating GDM reduced a composite perinatal outcome (death, bone fracture, shoulder dystocia, and nerve palsy) from 4% to 1% (p=0.01). The number needed to treat was 34. Additionally fewer babies were admitted to the neonatal unit (71% vs 61%). Landon et al. showed significant reduction in mean birth weight (3302g vs. 3408 g), neonatal fat mass (427g vs. 464 g), frequency of large-for-gestational-age infants (7.1% vs. 14.5%), birth weight greater than 4000 g (5.9% vs. 14.3%), shoulder dystocia (1.5% vs. 4.0%), and caesarean delivery (26.9% vs. 33.8%). Treatment of gestational diabetes mellitus, as compared with usual care, was also associated with reduced rates of preeclampsia and gestational hypertension (combined rates for the two conditions, 8.6% vs. 13.6%; P=0.01).
To the individual woman, a four-fold reduction in the risk of her baby dying, having permanent nerve damage or bone fracture is certainly worthy of consideration. Especially as the effective intervention can be as simple as monitoring home blood glucose levels and maintaining a healthy diet. Reducing neonatal admission is also beneficial both in terms of developing early bonding between mother and baby and managing cot availability and cost. The long-term impact of stillbirth, nerve palsy or bone injury is substantial both to individuals, families and society.
Perinatal mortality is at an all time low, targeting perinatal and maternal morbidity now becomes increasingly important. Further advancement may necessitate treating larger groups of women for relatively smaller benefit. This is common to almost all obstetric conditions in the developed world. However, it is the women, who potentially live with the consequences of non-intervention, who should be given the choice and not the medical profession who take a global, rather than individual view, of worthiness.
Competing interests:
No competing interests
02 April 2014
Kenneth K Hodson
Subspecialty Trainee in Maternal and Fetal Medicine
Rapid Response:
Re: Gestational diabetes: new criteria may triple the prevalence but effect on outcomes is unclear
The recent analysis of gestational diabetes (GDM) (BMJ 2014:348:g1567) summarises the on-going debate about whether to screen for and indeed treat gestational diabetes. The authors conclude that mild glycaemia ‘does not carry anything like the same degree of risk’ (as pre-existing type 1 or 2 diabetes) and imply that treating GDM is without clear evidence of clinically important benefit.
Two randomized controlled trials (mentioned, but not given much credit in the article) have established the clinical benefit of treating gestational diabetes. Crowther et al. showed that treating GDM reduced a composite perinatal outcome (death, bone fracture, shoulder dystocia, and nerve palsy) from 4% to 1% (p=0.01). The number needed to treat was 34. Additionally fewer babies were admitted to the neonatal unit (71% vs 61%). Landon et al. showed significant reduction in mean birth weight (3302g vs. 3408 g), neonatal fat mass (427g vs. 464 g), frequency of large-for-gestational-age infants (7.1% vs. 14.5%), birth weight greater than 4000 g (5.9% vs. 14.3%), shoulder dystocia (1.5% vs. 4.0%), and caesarean delivery (26.9% vs. 33.8%). Treatment of gestational diabetes mellitus, as compared with usual care, was also associated with reduced rates of preeclampsia and gestational hypertension (combined rates for the two conditions, 8.6% vs. 13.6%; P=0.01).
To the individual woman, a four-fold reduction in the risk of her baby dying, having permanent nerve damage or bone fracture is certainly worthy of consideration. Especially as the effective intervention can be as simple as monitoring home blood glucose levels and maintaining a healthy diet. Reducing neonatal admission is also beneficial both in terms of developing early bonding between mother and baby and managing cot availability and cost. The long-term impact of stillbirth, nerve palsy or bone injury is substantial both to individuals, families and society.
Perinatal mortality is at an all time low, targeting perinatal and maternal morbidity now becomes increasingly important. Further advancement may necessitate treating larger groups of women for relatively smaller benefit. This is common to almost all obstetric conditions in the developed world. However, it is the women, who potentially live with the consequences of non-intervention, who should be given the choice and not the medical profession who take a global, rather than individual view, of worthiness.
Competing interests: No competing interests