应用生物电阻抗法分析人体组成

目的：通过应用生物电阻抗法测定人体组成,探讨其对营养评价的临床意义。方法：利用生物电阻抗法测定７６例健康志愿者的人体组成。结果：男性体脂占体重的（１４．８１±４．８９）％,女性体脂则占体重的（２２．３３±５．５８）％,女性体脂含量明显大于男性（Ｐ＜０．０５）。随年龄增长,可出现体脂增加而瘦组织群减少的趋势。应用生物电阻抗法测定体脂含量,其肥胖检出率明显低于按理想体重法和体质指数（ＢＭＩ）法的检出率。结论：生物电阻抗法测定人体组成简便、准确,有助于临床客观地评价机体营养状况。     

生物电阻抗法与双能X线吸收法测量成人体成分指标的比较研究

目的 比较生物电阻抗法（bioelectrical impedance analysis,BIA）和双能X线吸收法（dual energy X-ray absorptiometry, DXA）测量成人体成分各指标之间的差异。方法 招募18～65岁成年受试者共计386名,同时采用BIA和DXA测量受试者的总体脂率、躯干体脂率、体脂含量和去脂体重。利用Pearson积矩相关系数评价两种方法测量结果的相关性,用配对t检验比较两种方法测量均值差异,用均方根误差（root mean squared error, RMSE）和最小乘积回归（ordinary least product regression, OLP）来评价两种方法测量结果的一致性。结果 BIA与DXA测量的男性和女性体成分指标的相关系数均在0.75以上（P <0.001）。BIA测量的男性总体脂率、躯干体脂率和体脂含量的结果均值分别低于DXA测量结果均值。BIA测量的男性和女性去脂体重结果均值显著高于DXA测量结果的均值（P<0.001）。男性和女性各测量指标RMSE均较小,各指标均存在固定偏差和比例偏差。结论 BIA...     

杜氏肌营养不良症的产前基因诊断

应用 XP_(21)区的 DNA 探针作限制性内切酶片段长度多态性连锁分析,对1例杜氏肌营养不良症(DMD)高危妊娠进行产前诊断,产前诊断为女性胎儿,是 DMD 基因携带者。产前诊断结果与分娩后的检查结果相符合。     

生物电阻抗法测量肥胖者体脂含量的应用方程

生物电阻抗是近年来被广泛应用的一种快速、简便、安全测量体成分的方法。本研究采用水下称重测量 1 96名 (男性 :66名 ;女性 :1 30名 ) 1 8～ 67岁肥胖受试者的体脂含量 ,并用生物电阻抗方法测定生物电阻抗值。结果表明用水下称重法测量的体脂含量和去脂体重的测量结果与文献中不同国家生物电阻抗推算方程的推算结果有显著的统计学差异 (P <0 0 1 )。本文通过用多元线性逐步回归和方差分析方法建立了适合我国肥胖人群特点的体成分推算方程 :BF =0 846 Wt- 0 1 85 Ht2 z - 2 361 Sex - 2 4 977。Ht:身高(cm) ,Wt:体重 (kg) ,Z :生物电阻抗 (Ω) ,Sex :性别 (男性 =1 ,女性 =0 )。方程的相关系数 :r =0 92 3 ,标准误 :S x=3 43 ,方差分析 (ANOVA)具有统计学意义 (F =365 73 ,P <0 0 0 1 )。     

杜氏肌营养不良临床特点及诊治进展

杜氏肌营养不良(Duchenne muscular dystrophy,DMD)是一种常见的X染色体连锁隐性遗传性肌肉疾病,临床上主要以糖皮质激素治疗为主。早期诊断、早期治疗可改善患者生活质量,延长患者生命,DMD新生儿筛查为其早期诊治提供可能。近年来DMD在药物治疗、基因治疗、骨髓干细胞移植等方面均取得重大进展。     

整体生物电阻抗法分析小儿身体组成的可行性

整体生物电阻抗(WBI)测量是成本低廉、操作简便的方法。我们连续5天在上、下午测量12名小儿WBI,以证实其稳定性;用水下浸入体密度法测量22名小儿的体脂(BF)和非脂肪组织(FFM),与WBI及体格指标行相关分析,以证实其分析小儿身体组成的准确性。上、下午Z均值间以及连续5天的Z均值间均无显著差异(P<0.05)。Zw/H~2与BF、H~z/Z与FFM的直线相关系数r分别为0.9617和0.9326(P<0.001),Z、H、W与BF及Z、H与FFM的偏相关系数r有显著性意义(P<0.05)。结果证明了该法分析小儿身体组成的可行性。     

生物电阻抗法测量7～10岁儿童总体水含量和去脂体重的预测模型

目的利用生物电阻抗方法测量儿童的体成分,建立适合我国儿童体成分的预测方程。方法在北京市采用目的抽样法选取409名7～10岁的儿童（男生220名,女生189名）,测量身高和体重,采用生物电阻抗仪测量全身电阻抗和电容抗,采用单标水法测量的总体水（totalbodywater,TBW）和去脂体重（fat—freemass,FFM）作为标准,用多元线性逐步回归法建立回归方程,并采用纯误差和Bland—Altman分析法来判断预测方程的准确度。结果TBW的预测方程=-6．893＋0．410x性别（男：1,女=0）＋0．273×年龄（岁）＋0．174x体重（k）＋0．081×身高（cm）＋0．206x阻抗指数（cm2/Ω）（R2=0．90,均方根误差=1．2kg）;FFM的预测方程=-9．742＋0．784x性别（男=1,女=0）＋0．429x年龄（岁）＋0．227×体重（kg）＋0．104x身高（cm）＋0．269×阻抗指数（cm2／Ω）（R2=0．90,均方根误差=1．6kg）。TBW和FFM的预测值与测量值间差异均无统计学意义,纯误差分别是1．4、1．8kg。TBW和FFM的测量值与预测值的差值与均值之间存在显著正相关性（相关系数分别为0．24、0．23,P〈0．01）。不同BMI分组的测量值与预测值间差异均无统计学意义。结论推导的预测方程有较高的精确度和准确度,能有效准确地预测我国7～10岁儿童的体成分。     

小儿整体生物电阻抗和体脂、瘦体重的相关分析

用长征Ⅰ型整体生物电阻抗仪测量22名6～7岁小儿的整体生物电阻抗值(Z),体脂(BF)、瘦体重(LBW)用水下浸入体密度法测得。直线相关分析:由Z、体重(W)或身高(H)所组成的两个生物电阻抗指数(BII)ZW/H~2或H~2/Z相应与BF或LBW的r值为0.9617和0.9326,(P<0.0001),显著高于所有体格测量指标与BF或LBW的r值(P均<0.05)。多元线性相关分析:ZH、W与BF及Z、H与LBW的偏相关系数有显著性意义(P<0.05),Z与BF及LBW的r值为最高。表明:生物电阻抗法可能是准确度较高的分析小儿身体组成的方法。     

中国7~18岁人群应用生物电阻抗法估算体脂方程

目的建立生物电阻抗方法(BIA)测量中国儿童青少年体脂含量的应用方程。方法按《中国学龄儿童青少年超重、肥胖筛查BMI分类标准》中各性别和年龄段超重的BMI参考值,将总人群分为体重正常组和超重肥胖组。以水下称重方法为标准方法,采用多元线性逐步回归方法,建立不同BMI水平7~18岁儿童青少年BIA的应用方程。结果体重正常组方程:去脂体重(FFM,kg)=0.406weight+2.918sex+0.315H2/z+0.843;超重肥胖组方程:FFM(kg)=0.358weight+1.571sex+0.358H2/z+0.603;总人群方程:FFM(kg)=0.290weight+2.222sex+0.427H2/z+1.547。三个方程的调整回归系数(r2)和标准误(SEE)分别为:0.940和2.36;0.955和2.46;0.942和2.53,方程的统计学检验均有显著性意义(ANOVA,P<0.001)。结论本研究建立的BIA应用方程与国内外同类研究相比,具有较高的可靠性。     

One-year increment of fat mass and lean body mass of Japanese school children using bioelectrical impedance

Bioelectrical impedance analysis (BIA) and skinfold thickness (SF) (triceps and subscapular) methods were applied to 436 Japanese school children (228 boys and 208 girls) aged from 9 to 11 years with a one-year follow-up to determine changes in body composition. By BIA oneyear increment (Δ) of lean body mass (LBM) for boys increased significantly (p<0.01) and Δ LBM was almost equivalent to that for Δ weight (Wt). Δ Wt and Δ fat mass (FM) between the age 10 (from ages 10 to 11) and age 11 (from ages 11 to 12) groups in girls achieved statistical significance (p<0.01 and p<0.001, respectively) and Δ Wt was almost completely comprised of the Δ FM in these age groups. Δ FM in die age 11 group for girls was statistically higher than that in the age 10 group, and this obvious increase of FM in the age 11 group was presumed to be die effect of menses in consideration of die maximum oneyear increment of Ht (Δ Ht) in die age 10 group. These results of the assessment of body composition by BIA supported those of previous reports, and therefore BIA can be considered as a useful mediod to estimate changes in body composition of school children because it is simple and non-invasive and can be performed rapidly.     

2015年中国15省(自治区、直辖市)18~65岁居民体脂率人群分布及其与体质指数关系

目的描述2015年中国15省(自治区、直辖市)18~65岁居民体脂率(body fat percentage,BF%)和体脂肪量的地区和人群分布特征,探讨体脂率与体质指数(body mass index,BMI)的关系。方法本研究利用2015年"中国居民营养状况变迁的队列研究"项目中有完整体格测量及相关人口经济学调查资料的10561名18~65岁成年人数据进行分析。采用生物电阻抗法测量调查对象体脂率和体重,分析不同性别成年人体脂率和体脂肪量在年龄、教育水平、家庭人均收入、地区和城乡之间分布的差异,并根据世界卫生组织(World Health Organization,WHO)推荐的体脂率的肥胖判定标准判断人群肥胖率。结果2015年中国15省(自治区、直辖市)18~65岁成年女性体脂率、体脂肪量分别为33.6%、19.5 kg,成年男性分别为23.0%、15.7 kg。体脂率、体脂肪量均呈现北方地区高于南方,差异有统计学意义(P<0.0001)。男性不同年龄、教育水平、家庭年人均收入水平、地域及城乡人群的体脂率和体脂肪量差异均有统计学意义(P<0.0001)。女性不同年龄、教育水平、地域的体脂率和体脂肪量差异均有统计学意义(P<0.0001),城乡和家庭收入水平差异没有统计学意义。按照WHO推荐的体脂率的肥胖判定标准,女性肥胖率42.0%,随年龄增长不断上升,60~65岁女性肥胖率高达52.4%。男性肥胖率37.1%,随着年龄增长呈上升趋势,但在60~65岁组下降。北方地区男女性肥胖率分别41.9%、45.6%,明显高于南方地区的34.3%、39.9%。BMI与BF%密切相关,但在超重人群中,体脂率达到肥胖水平的人超过50%。结论2015年中国15省(自治区、直辖市)不同性别成年人体脂率和体脂肪量存在明显的地区和人群差异,北方人群的肥胖率明显高于南方。     

The Stayhealthy bioelectrical impedance analyzer predicts body fat in children and adults

Bioelectrical impedance analysis (BIA) is a time-efficient and cost-effective method for estimating body composition. We hypothesized that there would be no significant difference between the Stayhealthy BC1 BIA and the selected reference methods when determining body composition. Thus, the purpose of the present study was to determine the validity of estimating percent body fat (%BF) using the Stayhealthy BIA with its most recently updated algorithms compared to the reference methods of dual-energy x-ray absorptiometry for adults and hydrostatic weighing for children. We measured %BF in 245 adults aged 18 to 80 years and 115 children aged 10 to 17 years. Body fat by BIA was determined using a single 50 kHz frequency handheld impedance device and proprietary software. Agreement between BIA and reference methods was assessed by Bland and Altman plots. Bland and Altman analysis for men, women, and children revealed good agreement between the reference methods and BIA. There was no significant difference by t tests between mean %BF by BIA for men, women, or children when compared to the respective reference method. Significant correlation values between BIA, and reference methods for all men, women, and children were 0.85, 0.88, and 0.79, respectively. Reliability (test-retest) was assessed by intraclass correlation coefficient and coefficient of variation. Intraclass correlation coefficient values were greater than 0.99 (P < .001) for men, women, and children with coefficient of variation values 3.3%, 1.8%, and 1.7%, respectively. The Stayhealthy BIA device demonstrated good agreement between reference methods using Bland and Altman analyses.     

External cross-validation of bioelectrical impedance analysis for the assessment of body composition in Korean adults

Bioelectrical impedance analysis (BIA) models must be validated against a reference method in a representative population sample before they can be accepted as accurate and applicable. The purpose of this study was to compare the eight-electrode BIA method with DEXA as a reference method in the assessment of body composition in Korean adults and to investigate the predictive accuracy and applicability of the eight-electrode BIA model. A total of 174 apparently healthy adults participated. The study was designed as a cross-sectional study. FM, %fat, and FFM were estimated by an eight-electrode BIA model and were measured by DEXA. Correlations between BIA_%fat and DEXA_%fat were 0.956 for men and 0.960 for women with a total error of 2.1%fat in men and 2.3%fat in women. The mean difference between BIA_%fat and DEXA_%fat was small but significant (P < 0.05), which resulted in an overestimation of 1.2 ± 2.2%fat (95% CI: -3.2-6.2%fat) in men and an underestimation of -2.0 ± 2.4%fat (95% CI: -2.3-7.1%fat) in women. In the Bland-Altman analysis, the %fat of 86.3% of men was accurately estimated and the %fat of 66.0% of women was accurately estimated to within 3.5%fat. The BIA had good agreement for prediction of %fat in Korean adults. However, the eight-electrode BIA had small, but systemic, errors of %fat in the predictive accuracy for individual estimation. The total errors led to an overestimation of %fat in lean men and an underestimation of %fat in obese women.