应用生物电阻抗法对临床评估达干体质量的血液透析患者的水负荷的研究

目的 应用生物电阻抗分析法评估正常人群和临床评估达干体质量的透析患者体内水的含量及其分布特点,并比较在两组人群之间的差异.方法 选石家庄市区健康志愿者240例作为对照组(A组),男120例,年龄(43.4±10.2)岁,记为A1组,女120例,年龄(44.7±13.5)岁,记为A2组;病例组(B组)选自2008年1～12月在我院血液净化中心临床法评估均达到干体质量的维持性血液透析的患者40例,男20例,年龄(45.6±10.8)岁,记为B1组,女20例,年龄(43.7±13.9)岁,记为B2组;所有患者均处于肾疾病的终末期,平均透析时间(20.0±7.2)个月.生物电阻抗测定并记录A组、B组透析前、B组透析后的总水含量占体质量的百分比(TBW%)、细胞外液占总水含量的百分比(ECW/TBW%)、细胞内液占总水含量的百分比(ICW/TBW%),与A组数据进行比较.同时密切观察并记录患者透析中的主诉、症状、血压、心率等.结果 B1组TBW%透析前与A1组比较(71.83±7.83)% vs(60.53±4.98)%和透析后与A1组比较(70.63±7.43)% vs(60.53±4.98)%,差异均有统计学意义(P<0.05),ECW/TBW%、ICW/TBW%则与A1组比较差异无统计学意义.②B2组TBW%透析前与A2组比较(71.28±10.38)% vs(59.07±6.73)%(P<0.05)和透析后与A2组比较(69.41±8.17)% vs(59.07±6.73)%(P<0.05),差异均有统计学意义,ECW/TBW%、ICW/TBW%则与A2组比较差异无统计学意义.结论 ①透析前患者TBW%高于正常人,增加的水在细胞内液和细胞外液是同步增加的.②透析后临床法评估达到干体质量的患者,用生物电阻抗测定TBW%仍高于正常人,说明临床评估干体质量的方法粗略,不精确.③生物电阻抗分析法通过对人体内水含量及其分布的测定,对干体质量的评估比临床法更准确.     

生物电阻抗矢量分析法评价维持性血液透析患者干体重初探

目的探索生物电阻抗矢量分析法（bioelectrical impedance vector analysis,BIVA）在评价维持性血液透析（maintenance hemodialysis,MHD）患者干体重（dryweight,DW）中的应用。方法选择北京大学第一医院肾脏内科血液透析室临床评价DW合适的MHD患者,透析前和透析后分别进行单频（50KHz）、全身生物电阻抗测量。收集北京石景山地区的健康查体人群作为对照。在电阻-电抗矢量图（RXc图）上分别绘制健康人群和MHD患者矢量的95%可信区间和健康人群的容受区间。根据透析前患者在健康人群容受区间图上的位置将MHD患者分为A（水负荷过重）、B（水负荷正常）两组,比较两组患者透析前高血压患病情况。根据透析后患者的矢量在容受区间图上的位置将患者分为水负荷过重（OH）组、水负荷正常（NH）组和脱水（DH）组,从而预测干体重调整方向,并比较三组患者透析前和透析后的血压变化。结果共测量290例健康成人,男∶女=149∶141;血液透析患者37例,男∶女=13∶24。相比健康对照,透析患者透析前的矢量较短,相角较小;透析后矢量均较透析前变长,相角变大,水合状态改善。A组高血压出现率为39.3%,而B组为22.2%。DH组血压平均水平较OH和NH组低,但没有统计学差异。BIVA方法评价干体重合适的患者与临床评价一致性为70.3%;BIVA预测11例患者需要调整DW,经过两周的观察,5人调整了干体重,调整方向与BIVA预测方向一致。结论在临床评估干体重合适的患者中,仍然有部分患者的透析前水负荷较重。BIVA方法能先于临床经验发现不合适的干体重,可以作为较为敏感的估计干体重的辅助工具。     

Comparison of the body fluid levels in healthy individuals and those with schizophrenia in Japan: using the bioelectrical impedance method

Polydipsia and water intoxication have been found to be care problems in people with schizophrenia in many countries. This Japanese study measured the body fluid distribution and body fat of 80 males with long standing schizophrenia and compared this to that of 64 healthy males, using bioelectrical impedance spectrum analysis (BIS). Participants with schizophrenia exhibited significantly lower percentages of intracellular fluid and total body fluid, and significantly higher percentages of fat. Moreover, the percentage of extracellular fluid was distributed over a wider range. When the percentage body fluid was compared between the two groups by matching body mass index and body fat, intracellular fluid was significantly lower for those participants with schizophrenia. There findings suggest that nurses and other health professionals need to be very cautious when attempting to modify the excessive drinking of fluids by patients with schizophrenia. In mistakenly trying to prevent water intoxication, they may in fact be contributing to dehydration.     

Use of bioelectrical impedance analysis in the evaluation, treatment, and prevention of overweight and obesity

PURPOSE: To present an overview of bioelectrical impedance analysis (BIA) and to familiarize nurse practitioners (NPs) with the potential benefits of using BIA in prevention, monitoring, and long-term follow-up of healthy individuals and those with chronic conditions (e.g., obesity). DATA SOURCES: Original research articles and comprehensive review articles identified through Medline, CINAHL, OVID, and electrical engineering databases. CONCLUSIONS: Obtaining serial measurements of percent body fat using BIA can identify patients at greatest health risk and gives NPs an additional tool to assess treatment response in patients seeking to lose or maintain body weight and/or increase muscle mass. IMPLICATIONS FOR PRACTICE: Traditionally, height/weight tables and body mass index have been used to assess body composition and diagnose overweight and obesity. More recently, BIA has emerged as a portable and simple-to-operate instrument to evaluate body composition in the clinical setting.     

Anthropometry,bioelectrical impedance and dual-energy X-ray absorptiometry in the assessment of body composition in elderly Finnish women

In this study, the bioelectrical impedance analysis (BIA), skinfold thickness measurement (STM) and dual-energy X-ray absorptiometry (DXA), as a reference method, were compared with each other in the assessment of body composition in elderly (62-72-year-old) Finnish women (n=93). BIA had better agreement with DXA in the assessment of fat free mass (FFM, R2=0.70, Sres=2.1) and fat mass (FM, R2=0.93, Sres=2.3) than the STM (FFM, R2=0.62, Sres=2.4; FM, R2=0.89,Sres=2.8). There was quite a large variation in the estimates when different BIA prediction equations were used. The equation developed in this study, FFM (kg)=-128.06 + 1.85 x BMI-0.63 x weight + 1.07 x height - 0.03 x resistance +10.0 x waist-hip ratio, yielded a small and unbiased error (0.5 +/- 1.6 kg), with a small residual standard deviation (R2=0.83, Sres=1.6). However, error associated with the estimate of FM was positively related to the degree of FM. BIA(Heitmann) equation yielded unbiased estimates of both FFM and FM (FFM, R2=0.77, Sres=1.8; FM, R2=0.95, Sres=1.9). Both the STM and BIA (manufacturer's equation) resulted in error which was statistically significant and positively correlated with FFM and FM. These results indicate that BIA prediction equations, chosen with care, can improve the performance of equations based upon anthropometric measurements alone in the assessment of body composition in elderly women.     

乳腺癌患者内分泌治疗期间人体成分的调查

【摘要】 目的 观察乳腺癌患者内分泌治疗期间人体成分情况,为动态监测乳腺癌患者营养状况提供依据。方法 利用多频分节段生物电阻抗（segmental multi-frequency bioelectrical impedance analysis, SMFBIA）方法分析183例内分泌治疗期乳腺癌患者的人体成分,探讨不同内分泌治疗方案及具体药物对乳腺癌患者人体成分的影响。结果 183例内分泌治疗期乳腺癌患者中45.36%(83/183)为正常体重,50.82%（93/183）为超重或肥胖, 81.42%（149/183）患者PBF处于超标准（＞28%）,49.73% (91/183)患者腰围处于超标准（＞80cm）,且内分泌治疗对患者BMI、体脂肪、体脂百分比、内脏脂肪面积、腰围、上臂肌围、ECW/TBW表现明显。结论 乳腺癌患者内分泌治疗期间存在营养过剩的现象,不同内分泌治疗方案对乳腺癌患者营养状况具有一定影响,故应定期监测患者人体成分,以便全面客观评价患者营养状况,有效促进患者健康体重管理,构建获取营养相关信息的支持平台,提高诊疗效果,延长患者生存期。     

Effect of bioimpedance body composition analysis on function of implanted cardiac devices

Background: It is routinely recommended that patients with pacemakers, implantable cardioverter defibrillators (ICD), and cardiac resynchronization therapy‐defibrillators (CRT‐D) avoid bioelectrical impedance analysis (BIA)—a commonly used method to estimate body composition—because of the concern for the potential for BIA interference with pacemaker or ICD function. However, the prevalence of such interference is not known. Objective: Assess for incidence of interference between BIA and ICD or CRT‐D devices. Methods and Results: Twenty patients with heart failure and cardiac implanted electronic devices (50% ICD, 50% CRT‐D) underwent BIA during real‐time device interrogation to detect interference. Study patients were 90% male, with mean age 54 ±14 years, and mean LVEF 23 ± 11%. Devices from all four leading cardiac device manufacturers were included. Device therapies were temporarily disabled to prevent inappropriate shocks. During body composition testing using BIA, no evidence of interference with ICD function was seen in any patient, including no telemetry disruption, no oversensing on any lead, and no patient symptoms. Conclusions: Despite the manufacturers’ recommendation to avoid BIA in patients with ICDs, this study showed no evidence of any interference in 20 patients. Bioimpedance analysis might be safe in such patients, but further confirmatory studies are required. (PACE 2012; 35:681–684)     

Effectiveness and tolerability of rosiglitazone on insulin resistance and body composition in nondiabetic Thai patients undergoing continuous ambulatory peritoneal dialysis: A 12-week pilot study

Background: Patients with chronic renal insufficiency, especially those undergoing continuous ambulatory peritoneal dialysis (CAPD), normally have insulin resistance due to deficiencies in insulin secretion and degradation, as well as tissue resistance to insulin at both receptor and postreceptor levels.Objective: The aim of this study was to investigate the effectiveness and tolerability of rosiglitazone on insulin resistance and body composition in patients without diabetes mellitus (DM) undergoing CAPD.Methods: This pilot study included a pretest and posttest with a repeated-measure design in a small number of patients. CAPD patients without DM received rosiglitazone 2-mg tablets BID for 12 weeks. Homeostasis Model Assessment Index of Insulin Resistance (HOMA-IR) and bioelectrical impedance analysis (BIA) were used to assess insulin resistance and body composition, respectively. Tolerability was assessed using laboratory analyses as well as physical examination findings to evaluate peripheral edema. Peripheral edema was assessed by the study investigators.Results: Thirteen Thai patients (mean [SD] age, 54.17 [11.42] years [range, 35-85 years]; body mass index [BMI], >20 to <30 kg/m²; fasting blood glucose [FBG] concentration, <5.39 mmol/L) were included in the study. One patient was withdrawn due to illness unrelated to the study. No significant difference was found in FBG concentration between baseline and posttreatment (after 12 weeks of treatment) (5.45 [0.59] vs 5.24 [0.51] mmol/L), but fasting plasma insulin concentrations (28.50 [23.70] vs 10.15 [4.22] μIU/mL; P = 0.005) and HOMA-IR score (6.70 [5.23] vs 2.40 [1.15]; P = 0.011) were significantly lower. There were no significant changes in weight or BMI from baseline to posttreatment. Seven subjects (58.3%) experienced weight gain at week 4, while 2 patients (16.7%) still had weight gain after 12 weeks of treatment. A significant increase was found between baseline and posttreatment in total body water (38.03 [4.55] vs 42.44 [5.99] L; P = 0.018), extracellular fluid (20.24 [3.75] vs 26.22 [8.69] L; P = 0.005), plasma fluid (4.29 [0.80] vs 5.20 [0.93] L; P = 0.005), and interstitial fluid (14.99 [2.78] vs 17.68 [3.07] L; P = 0.040). Using BIA, no significant changes were observed in intracellular fluid, fat mass, or liver function. After 12 weeks of rosiglitazone administration, 2 patients (16.7%) had mild edema.Conclusions: Rosiglitazone 2 mg BID for 12 weeks was associated with significantly improved insulin resistance in this small group of nondiabetic Thai patients undergoing CAPD. There was a significant increase in total body water and extracellular fluid after administration of rosiglitazone for 12 weeks. There were no significant changes in FBG, weight, or BMI.