To assess the associations of pre-pregnancy cardiorespiratory fitness, moderate-to vigorous-intensity physical activity (MVPA), and time spent watching television with subsequent development of gestational diabetes mellitus (GDM).
Participants were 1,333 women enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study who did not have diabetes either at baseline (1985-86) or prior to births occurring after baseline. Baseline fitness was estimated using a graded symptom-limited maximal exercise treadmill test and expressed in metabolic equivalent (MET) units. Baseline MVPA (exercise units/day) was measured using the CARDIA physical activity history questionnaire, and television viewing (hours/day) was assessed by self-report in 1990-91. Logistic regression analysis was used to derive odds ratios (OR) and 95% confidence intervals (CI), adjusting for time from baseline to delivery and baseline study center, age, race, education, parity, family history of diabetes, smoking, alcohol, saturated fat intake, waist circumference, HOMA-IR, and HDL-Cholesterol.
Over 25 years of follow up, 164 women developed GDM. The odds of developing GDM were 21% lower for each 1 standard deviation increment in baseline level of fitness (2.3 METs; OR 0.79, 95% CI 0.65, 0.96). Pre-pregnancy MVPA and television viewing were not statistically associated with the development of GDM.
Study findings indicate that objectively assessed pre-pregnancy fitness, but not self-reported MVPA or television time, is associated with GDM. Clinicians should counsel women on the benefits of improving fitness in the pre-conception period, particularly among women at greater risk for GDM.
1Department of Health and Human Physiology, University of Iowa, Iowa City, IA; 2Department of Exercise Science and Sport Management, Kennesaw State University, Kennesaw, GA; 3Department of Public Health, Texas Tech University Health Sciences Center, Abilene, TX; 4Department of Obstetrics and Gynecology, University of North Carolina, Chapel Hill, NC; 5Division of General Internal Medicine, John Hopkins University School of Medicine, Baltimore, MD; 6Division of Preventive Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL; 7Division of Cardiovascular Sciences, National Heart, Lung, and Blood Institute, Bethesda, MD; 8Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN; 9Division of Research, Kaiser Permanente Northern California, Oakland, CA
Corresponding Author: Kara M. Whitaker, E112 Field House, Iowa City, IA; Telephone: 319-335-7907; Fax: 319-335-6669; E-mail: email@example.com
The Coronary Artery Risk Development in Young Adults Study (CARDIA) is supported by contracts HHSN268201300025C, HHSN268201300026C, HHSN268201300027C, HHSN268201300028C, HHSN268201300029C, and HHSN268200900041C from the National Heart, Lung, and Blood Institute (NHLBI), the Intramural Research Program of the National Institute on Aging (NIA), and an intra-agency agreement between NIA and NHLBI (AG0005). The analyses were supported by grants from R01 DK090047 (Gunderson, PI) and K01 DK059944 (Gunderson, PI) from the National Institute of Diabetes, Digestive and Kidney Diseases. KMW was supported by research training grant T32 HL007779. CEL, PJS, and EPG report grant funding from the National Institutes of Health (NIH) during the conduct of this study. EPG also reports funding from Jansen Pharmaceutical Inc. that was unrelated to this study. No other conflicts of interest were reported. The views expressed in this manuscript are those of the authors and do not necessarily represent the views of the NHLBI, the NIH, the U.S. Department of Health and Human Services, or ACSM. The results of this study are presented clearly, honestly, and without fabrication, falsification, or inappropriate data manipulation.
Accepted for Publication: 1 March 2018