基于生物电阻抗原理的体脂率指标在大学生肥胖判定中的价值

Value of body fat percentage index based on the bioelectrical impedance in the judgment of obesity among undergraduate students

目的采用不同方法判断大学生肥胖,探讨生物电阻抗原理检测的体脂率指标在大学生肥胖判定中的价值。方法以97名未参加过系统运动训练的全日制非体育专业大学生为研究对象,分别采用双能X线吸收法(dual energy X-ray absorptiometry,DEXA)、生物电阻抗法测量的全身体脂率、体质量指数(BMI)判定肥胖率。以DEXA判定结果为金标准,进行BMI法和生物电阻抗法测量结果的真实性评价和可靠性评价,并调整BMI判断肥胖的截断值、生物电阻抗法测量的体脂率。结果采用DEXA测量的体脂率为指标,男、女大学生肥胖率分别为53.5%(23/43)和59.3%(32/54);采用BMI指标,男、女大学生肥胖率分别为9.3%(4/43)和3.7%(2/54);采用生物电阻抗法测量的体脂率为指标,男、女大学生肥胖率分别为32.6%(14/43)和29.6%(16/54)。以DEXA判定结果为金标准,生物电阻抗法判定男、女大学生肥胖的灵敏度高于BMI,生物电阻抗法判定男、女大学生肥胖的漏诊率低于BMI;BMI和生物电阻抗法判定女大学生肥胖的准确度均低于男大学生;BMI法判断男、女大学生肥胖的Kappa值均低于生物电阻抗法。结论生物电阻抗法判定大学生肥胖具有较好的诊断效能,同时其测量方法简便、成本低、辐射低,适于在群体检测中推广。

Objective To identify obesity among undergraduate students based on the different methods and the value of body fat rate index based on bioelectrical impedance in identifying obesity among obese university students was explored.Methods A total of 97 full-time non-PE university students who have not participated in systematic exercise training were included.The obesity was determined by the body fat percentage and BMI valueweremeasured by the dual-energy X-ray absorptiometry(DEXA)and bioelectrical impedance respectively.Taking the DEXA test results as the gold standard,the authenticity and reliability of BMI and bioelectrical impedance method were evaluated,and the cut-off value for obesity measured by BMI and the body fat rate measured by bioelectrical impedance were adjusted.Results The obesity rates of male and female college students were 53.5%(23/43)and 59.3%(32/54),respectively according to the body fat percentage measured by the DEXA test.Taking the BMI value as standard,the obesity rate of maleand female college students were 9.3%(4/43)and 3.7%(2/54),respectively.Using body fat percentage measured by bioresistive resistance method as a standard,the obesity rates of male and female university students were 32.6%(14/43)and 29.6%(16/54),respectively.Taking DEXA test results as the gold standard,the sensitivity of the bioelectrical impedance methods were higher than those of the BMI in the male and female college students,and the omission diagnosis rate of the bioelectrical impedance method was lower than the BMI.The accuracy of BMI and bioelectrical impedance methods in female students was lower than those of males.The values of the Kappa for determining obesity for both male and female university students for the BMI method were lower than for the bioelectrical impedance method.Conclusions The bioelectrical impedance is a useful diagnostic tool for determining obesity in university students.At the same time,it is a simple,low cost and low radiation measurement method,which makes it suitable for popularization in group detection.