OBJECTIVE: To investigate the influence of prior food ingestion on the predictive value of a screening test for gestational diabetes mellitus.
METHODS: This prospective, nonrandomized study enrolled 1,387 pregnant women who underwent the 50-g glucose challenge test. Gestational diabetes mellitus was diagnosed according to the National Diabetes Data Group criteria. A nutritional survey of dietary information before the glucose challenge test was conducted. The patients were stratified into three groups based on the time of last food ingestion (fasting interval): 1 hour or less, 1–2 hours, and more than 2 hours. The more than 2-hours fasting interval group was defined as the “fasting” group, and the combined 1 hour or less and 1–2 hours fasting interval groups were defined as the “fed” group. We calculated the positivity rate and the positive predictive value to detect the predictive value.
RESULTS: Among women who fasted 1 hour or less, 1–2 hours, and more than 2 hours before a glucose challenge test, 2.5%, 3.1%, and 6.9% were diagnosed with gestational diabetes mellitus, respectively. The positive predictive value of the glucose challenge test was greater in the fasting group than in the fed group (27.1% compared with 13.7%, P=.003). A multinomial logistic analysis showed that gestational diabetes mellitus was more prevalent in the fasting group than in the fed group (adjusted odds ratio 2.86, 95% confidence interval 1.65–4.95).
CONCLUSION: Our findings suggest that food intake influences the predictive value of the gestational diabetes screening test.
LEVEL OF EVIDENCE: II
Food intake influences the predictive value of the gestational diabetes screening test.
Departments of Obstetrics and Gynecology, Medical Research, Nutrition, and Community Health, Ditmanson Medical Foundation, Chia-Yi Christian Hospital, Chia-Yi City, Taiwan.
Corresponding author: Yuan-Horng Yan, MD, MSc, Ditmanson Medical Foundation Chia-Yi Christian Hospital, 539 Chung-Shau Road, Chia-Yi City 600, Taiwan; e-mail: email@example.com.
Financial Disclosure The authors did not report any potential conflicts of interest.
The results of this study were presented at the 9th International Diabetes Federation Western Pacific Region Congress (9th IDF-WPR) and the 4th Scientific Meeting of the Asian Association for the Study of Diabetes (4th AASD), Kyoto, Japan, November 24–27, 2012.
The authors thank the staff of the Department of Community Health for their assistance with interviews of the pregnant women and collection of the questionnaire. The authors also thank American Journal Experts for editing assistance.