過重停經婦女之身體組成成分：生物電阻抗分析儀與雙能量X光吸收儀之效度分析

Abstract

目的：本研究探討生物電阻抗分析儀與雙能量X光吸收儀量測停經婦女身體組成成分之效度比較，並探究肥胖是否會影響所測量之結果。 方法：本研究為觀察性研究，將招募年齡大於50歲之停經婦女受試者，再將這些受試者依中華民國衛生福利部之身體質量指數標準分為正常體重組（n = 34， BMI < 24 kg/m2）與過重組（n = 16，BMI ≥ 24 kg/m2 ）。身體組成成分將以雙能量X光吸收儀作為黃金標準，與生物電阻抗分析儀所測得之結果，進行分析比較。將使用淨相關係數針對體脂肪重、四肢個別肌肉重、以及全身肌肉重進行相關性之分析，顯著水準設定為0.05。 結果：50名停經婦女（65.08 ± 6.94歲）之雙能量X光吸收儀與生物電阻抗分析儀所測得之四肢肌肉總重量，兩種儀器所測得之結果呈高度正相關性（0.75 < r < 0.82；p<0.05）；其中，肥胖組的相關性略低於正常體重組。 結論：生物電阻抗分析儀測量的結果與雙能量X光吸收儀，在正常體重或過重之停經婦女所測得之身體組成成分結果皆相似，除左右下肢全身肌肉重在正常體重組或過重組中，使用生物電阻抗分析儀量測之結果較雙能量X光吸收儀高。可用作為停經婦女臨床上參考之指標，但須注意是儀器廠牌或型號之間的準確性可能會略有不同，在使用前仍須個別做單獨測試以確保其效果。

Purpose: This study was to compare the validity of bioelectrical impedance analysis vs. dual-energy X-ray absorptiometry to measure the results of body composition in postmenopausal women and investigate whether overweight would affect the resulted. Methods: This observational study will recruit postmenopausal participants aged older than 50 years old and based on Health Promotion Administration of Body Mass Index (BMI) classified into normal weight group (n = 34, BMI < 24 kg/m2) and overweight group (n = 16, BMI ≥ 24 kg/m2). Body composition will use dual-energy X-ray absorptiometry as the gold standard, compared with the results of bioelectrical impedance analysis. Partial correlation will be used to analysis the correlation of body fat and appendicular skeletal muscle mass. The significant α-level was set at 0.05. Results: A total of 50 postmenopausal women were enrolled in this study (65.08±6.94 years old). The data was significant between methods of dual-energy X-ray and bioelectrical impedance analysis in regard to appendicular skeletal muscle (ASM) in both normal weight and overweight groups, the results of two measurement methods had a good to excellent correlation coefficient (0.75 < r < 0.82; p<0.05); whereas the overweight group was slightly less correlated than normal weight group. Conclusions: The results of bioelectrical impedance analysis and dual-energy X-ray absorptiometry were highly correlated and poor absolute agreement in the body composition of normal weight or overweight postmenopausal women. However, the use of BIA as an alternative to DXA in clinical setting for assessment of an individual’s body composition in normal weight and overweight populations are limited. BIA systematically overestimate bone mineral content and underestimate body fat and muscle mass.