University of Turku and Turku University Hospital, Department of Obstetrics and Gynecology, Turku, Finland.
University of Turku, Institute of Biomedicine, Turku, Finland.
Nutrition. 2019 Apr;60:227-229. doi: 10.1016/j.nut.2018.09.035. Epub 2018 Oct 19.
Body composition measurements with air displacement plethysmography (ADP) define body volume, which must be corrected for thoracic gas volume (TGV). We hypothesized that physiologic changes owing to pregnancy could affect the accuracy of predicted TGV and introduce errors into body composition measurements.
We investigated the effect of measuring versus predicting TGV on the accuracy of body composition calculations measured with ADP in overweight and obese pregnant women. The fat and fat-free masses of 110 women were determined with ADP with predicted and measured TGV.
Measured TGV decreased from early to late pregnancy (P = 0.0002). Compared with measured TGV, predicted TGV was 6.3% higher during early gestation and 12.6% higher during late gestation (both P ≤ 0.001). The use of predicted instead of measured TGV in body composition calculations resulted in an overestimation of fat mass by 0.8% during the early stage, and 2.6% during the late stage of pregnancy (both P ≤ 0.001).
Measuring TGV increases the accuracy of body composition measurement by ADP in overweight and obese women, particularly during the late stage of pregnancy.
空气置换体描仪（ADP）进行的人体成分测量定义了人体体积，必须对其进行校正以得到胸气量（TGV）。我们假设，妊娠引起的生理变化可能会影响 TGV 的预测准确性，并导致人体成分测量出现误差。
我们研究了在超重和肥胖孕妇中，测量与预测 TGV 对 ADP 测量的人体成分计算准确性的影响。使用 ADP 对 110 名女性的脂肪和去脂体重进行了测量，同时还对 TGV 进行了预测。
TGV 在妊娠早期到晚期逐渐下降（P=0.0002）。与测量的 TGV 相比，预测的 TGV 在妊娠早期高 6.3%，在妊娠晚期高 12.6%（均 P≤0.001）。在人体成分计算中使用预测 TGV 而不是测量 TGV，会导致脂肪量在妊娠早期高估 0.8%，在妊娠晚期高估 2.6%（均 P≤0.001）。
在超重和肥胖的女性中，测量 TGV 可提高 ADP 人体成分测量的准确性，尤其是在妊娠晚期。
