Women who develop gestational diabetes (GD) during pregnancy have a seven-and-a-half times increased risk of developing type 2 diabetes post-birth, which lasts throughout their lifetime. However, there is no agreed policy on the long-term follow up of these women and many do not return for the currently recommended 6-week post-birth diabetes check. An Article in this week's diabetes special issue of The Lancet says that the strength of the association suggests that both disorders have an overlapping cause—and this should act as an incentive for women to attend the recommended post-birth check. This attendance could be an opportunity to provide advice on diet and exercise, and treatments to delay or prevent onset of diabetes—as well as alerting these women to symptoms of future diabetes, and to alert general practitioners responsible for their long-term care.
GD is defined as glucose intolerance that is first detected during pregnancy, and affects up to 1 in 20 pregnancies. After birth, the woman's blood sugar control is restored to pre-pregnancy levels, but affected women remain at high risk of type 2 diabetes in the future. Dr David Williams (Institute for Women's Health, University College London (UCL) UK) and colleagues from UCL and the London School of Hygiene and Tropical Medicine did a meta-analysis of 20 studies that included some 675,000 women of whom 10,859 developed type 2 diabetes. They found that women with GD were around seven-and-a-half times more likely to develop type 2 diabetes after pregnancy than those with normal blood sugar control during pregnancy.
The authors conclude that further studies are needed to establish features for the identification of a mother with GD at particularly high risk of developing type 2 diabetes. They add: "The increased risk in relative risk of type 2 diabetes reported in this meta-analysis might help motivate mothers to attend screening programmes, and health-care professionals to increase uptake to these programmes or perhaps suggest the best time for reassessment. Since the risk of type 2 diabetes seems to be maintained for several years, consideration of whether any form of continuous assessment would lead to health gains is important."
"Women who have had gestational diabetes also have increased lipid concentrations and blood pressure, and type 2 diabetes is estimated to confer an equivalent risk of ageing 15 years. Early identification and treatment of these factors could also help to reduce premature cardiovascular and renal diseases in this group of individuals...Resolution of the metabolic changes after pregnancy could provide an opportunity to test the effectiveness of interventions for primary prevention of type 2 diabetes...The effectiveness and cost-effectiveness of interventions would need to be tested in clinical trials."
In an accompanying Comment, Dr Rhonda Bentley-Lewis, Brigham and Women's Hospital, Boston, MA, USA, says: "The present task is to ensure that this information is disseminated to clinicians and that the information is used to target prevention efforts to those who have had gestational diabetes...we as clinicians are afforded the rare opportunity to alter the natural course of disease and change the future health of women today."
Dr David Williams, Institute for Women's Health, University College London (UCL), UK T) +44 (0) 7930 362849 E) d.j.williams@ucl.ac.uk
Dr Rhonda Bentley-Lewis, Brigham and Women's Hospital, Boston, MA, USA T) +1 617-525-8444 E) rbentleylewis@partners.org
For full Article and Comment see: http://press.thelancet.com/gd.pdf and linked Editorial: http://press.thelancet.com/diabetesed.pdf
Journal
The Lancet