Oral Presentation International Association of the Diabetes and Pregnancy Study Groups 2022 - Hosted by ADIPS

Are there ethnic differences in the development of gestational diabetes mellitus across pregnancy? Results from the Treatment of Booking Gestational Diabetes Mellitus study (#39)

David Simmons 1 , Jincy Immanuel 1 , Helena Teede 2 , N Wah Cheung 3 , Bill Hague 4 , Christopher Nolan 5 , Michael Peek 6 , Mark Mclean 7 , Jeff Flack 8 , Emily Hibbert 9 , Vincent Wong 10 , Jürgen Harreiter 11 , Alexandra Kautzky-Willer 11 , Arianne Sweeting 12 , Emily Gianatti 13 , V Mohan 14 , Uma Ram 14 , Helena Backman 15
  1. School of Medicine, Western Sydney University, Campbelltown, NSW, Australia
  2. Monash University, Melbourne, Victoria, Australia
  3. Westmead Hospital, Sydney, NSW, Australia
  4. Robinson Research Institute, The University of Adelaide and Women’s and Children’s Hospital, Adelaide, South Australia, Australia
  5. Canberra Hospital and Australian National University, Canberra, ACT, Australia
  6. Australian National University, Canberra, ACT, Australia
  7. Blacktown Hospital, Sydney, NSW, Australia
  8. Bankstown-Lidcombe Hospital, Sydney, NSW, Australia
  9. Nepean Hospital, Sydney, NSW, Australia
  10. Liverpool Hospital, Sydney, NSW, Australia
  11. Gender Medicine Unit, Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
  12. Royal Prince Alfred Hospital, Sydney, NSW, Australia
  13. Fiona Stanley Hospital, Murdoch, Western Australia
  14. Seethapathy Clinic and Hospital, Chennai, India
  15. Örebro Hospital, Örebro, Sweden

Background: Non-Europid background is a known risk factor for gestational diabetes mellitus (GDM), and early screening is recommended for those from ethnic minority groups. This study investigates the specific risk associated with the presence of early (booking)GDM among women of non-Europid background.

Methods: Pregnant women with known risk factors for GDM enrolled in the Treatment of Booking Gestational Diabetes Mellitus (TOBOGM) trial, who underwent an oral glucose tolerance test (OGTT) at booking and at 24–28 weeks were studied. Ethnicity was self-reported. GDM was determined using World Health Organisation criteria. The association between ethnicity and GDM risk was tested using multivariate logistic regression analysis, adjusting for maternal age, booking BMI, previous GDM, family history of diabetes, and history of polycystic ovarian syndrome. Adjusted odds ratios (aORs) with 95%CI are reported.

Results: Among 3629 women, 42.2% were Europid, 33.0% were South Asian/Middle Eastern (SA/ME), and 24.7% were others. Total GDM prevalence was 33.3%, and the risk of GDM was greater with non-Europid ethnicity (aOR (95%CI) 1.85 (1.55–2.20), particularly with SA/ME ethnicity (aOR (95%CI) 2.07(1.70–2.52). The prevalence of booking and late GDM was 21.8% (n = 791) and 11.5% (n = 461), respectively. Mean (sd) age of the booking GDM cohort was 32.4(4.8) years; and of those with late GDM was 31.5(4.8) years (p = 0.002). Mean (sd) BMI for booking and late GDM were 32.5 (8.1) and 29.8 (6.7) kg/m2, respectively (<0.001). Ethnic distribution was similar (Europid, SA/ME, others: 39.1%, 36.5%, and 24.4% vs. 37.0%, 36.8%, and 26.2%, respectively (p = 0.72). Compared with Europid, SA/ME and others in the booking GDM group had higher 1-hour and 2-hour glucose values (fasting glucose (mmol/l): 5.1(0.4),  5.1(1.6), vs 5.0 (0.6), p = 0.11; 1-hour glucose: 8.7(2.0), 9.3(2.0), vs 9.4(2.0), p = 0.001; 2-hour glucose: 7.0(1.6), 7.5(1.6), vs 7.6 (1.7), p<0.001), whereas OGTT values did not differ among ethnic groups in the late GDM group. While non-Europid women had a higher risk of developing both booking and late GDM (aOR (95%CI) 1.75 (1.44–2.12) and aOR (95%CI) 1.62 (1.26–2.07), respectively), among those with GDM, the proportion with GDM present in early pregnancy was similar between non-Europid and Europid women (aOR (95%CI) 1.25 (0.94–1.66)). 

Conclusion: Among women with risk factors, ethnic differences exist both in the proportion of women identified with booking and late GDM and in the glucose profile of those diagnosed. Ethnic variations in booking 1-hour and 2-hour glucose should be further studied to elucidate their implications on pregnancy outcomes.