Associations of body composition and physical fitness with gestational diabetes and cardiovascular health in pregnancy: Results from the HealthyMoms trial

Abstract

The aim of this study was to examine associations of body composition (fat mass index, % fat mass, fat-free mass index, body mass index) and physical fitness (cardiorespiratory fitness and handgrip strength) with gestational diabetes and cardiovascular health in early pregnancy. This cross-sectional study utilized baseline data ( n \u2009=\u2009303) collected in early pregnancy from the HealthyMoms trial. Body composition was measured using air-displacement plethysmography, cardiorespiratory fitness was assessed by means of the 6-min walk test and handgrip strength using a dynamometer. Logistic regression was used to estimate odds ratios (ORs) for gestational diabetes as well as high (defined as 1\u2009SD above the mean) blood pressure, homeostatic model assessment for insulin resistance (HOMA-IR), and metabolic syndrome score (MetS score) per 1\u2009SD increase in body composition and fitness variables. Fat mass index, % fat mass and body mass index were all strongly associated with gestational diabetes (ORs: 1.72–2.14, P \u2009≤\u20090.003), HOMA-IR (ORs: 3.01–3.80, P \u2009<\u20090.001), blood pressure (ORs: 1.81–2.05, P \u2009<\u20090.001) and MetS score (ORs: 3.29–3.71, P \u2009 < \u20090.001). Associations with fat-free mass index were considerably weaker (ORs: 1.26–1.82, P \u2009=\u20090.001–0.15) and were strongly attenuated after adjustments for fat mass index (ORs: 0.88–1.54, P \u2009=\u20090.039–0.68). Finally, greater cardiorespiratory fitness was associated with lower risk of high HOMA-IR and MetS score (ORs: 0.57–0.63, P \u2009\u2009≤\u20090.004) although these associations were attenuated when accounting for fat mass index (ORs: 1.08-1.11, P \u2009≥\u20090.61). In conclusion, accurately measured fat mass index or % fat mass were strongly associated with gestational diabetes risk and markers of cardiovascular health although associations were not stronger than the corresponding ones for body mass index. Fat-free mass index had only weak associations with gestational diabetes and cardiovascular health which support that the focus during clinical care would be on excess fat mass and not fat-free mass.