Obesity, and particularly central adiposity, and inactivity are associated with diabetes in the general adult population. During pregnancy, insulin resistance is likely, however its relationships with inactivity and central fat accumulation are not fully understood.
PURPOSE: To test the hypothesis that central adiposity and physical inactivity are strong predictors of gestational insulin resistance.
METHODS: Twenty-eight nulliparous pregnant women (68% Caucasian, mean age 27.2 ± 4.5 years) were recruited from a partner OB/GYN clinic. Between 16-23 weeks gestation, body composition assessments, including bioimpedance analysis (InBody 720) and intra-abdominal adipose tissue (IAAT via ultrasound), along with 7-day accelerometry (Actigraph GT3x) were conducted. Fasting glucose and insulin were assessed at 24-26 weeks and used to compute the homeostasis assessment model of insulin resistance (HOMA-IR). Average daily sedentary time was calculated from the four most compliant days of seven. Pearson correlation and linear regression analyses were used to determine relationships.
RESULTS: When controlling for age and race, HOMA-IR was strongly associated with IAAT (r=0.637, p=0.026) and percent body fat (r=0.569, p=0.027), but not with sedentary time (r=-0.091, p=0.748). Moreover, linear regression revealed that IAAT (β =0.580, p=0.037), but not sedentary time (β= -0.067, p=.785), was a significant predictor of HOMA-IR in a model including maternal age. However, the overall model was unable to achieve significance (R^2= 0.371, p= 0.15).
CONCLUSIONS: Abdominal fat distribution, but not sedentary behavior, is an independent predictor of insulin resistance during pregnancy. Supported by internal grants from the Office of the Vice President of Research and Center for Excellence in Teaching and Leadership, Kennesaw State University.