老年慢性阻塞性肺病稳定期患者家庭肠内营养治疗疗效观察

目的探讨家庭肠内营养支持在合并营养不良的老年慢性阻塞性肺疾病（chronic obstructive pulmonary disease, COPD）稳定期患者中的应用效果。 方法选取2016年4月至2018年4月在内蒙古医科大学第三附属医院治疗并出院的合并营养不良的老年COPD稳定期患者155例，出院后给予常规饮食治疗79例（对照组），常规饮食+肠内营养混悬液（能全力，500 kcal/瓶）支持治疗76例（观察组）。随访1个月后观察两组患者的营养状况[包括BMI、血清白蛋白（ALB）、总蛋白（TP）、血红蛋白（Hb）]、肺功能状况[包括用力肺活量（forced vital capacity，FVC）、第1秒钟用力呼气容积（forced expiratory volume，FEV1）、FEV1/ FVC、FEV1占预计值的百分比（FEV1%）]、运动耐量（采用6 min步行试验评估）及生活质量情况（采用圣乔治呼吸问卷评估）。两组间比较采用t检验。 结果与对照组患者比较，观察组患者BMI及ALB水平明显升高（t=10.465、6.189，P<0.05），TP及Hb水平无明显变化（t=1.310、1.302，P>0.05），FVC、FEV1、FEV1/FVC、FEV1%均明显增加（t=11.999、19.654、13.418、16.924，P<0.05），生活质量症状评分、活动评分、影响评分及总分均明显下降（t=15.303、6.773、23.600、14.766，P<0.05），6MWT明显增加（t=111.962，P<0.05）。 结论家庭肠内营养支持可改善COPD稳定期合并营养不良的老年患者的营养状态、肺功能、活动耐量以及患者的生活质量。     

Obstructive and restrictive spirometric patterns: fixed cut-offs for FEV1/FEV6 and FEV6.

The purpose of this study was to determine fixed cut-off points for forced expiratory volume in one second (FEV(1))/FEV(6) and FEV(6) as an alternative for FEV(1)/forced vital capacity (FVC) and FVC in the detection of obstructive and restrictive spirometric patterns, respectively. For the study, a total of 11,676 spirometric examinations, which took place on Caucasian subjects aged between 20-80 yrs, were analysed. Receiver-operator characteristic curves were used to determine the FEV(1)/FEV(6) ratio and FEV(6) value that corresponded to the optimal combination of sensitivity and specificity, compared with the commonly used fixed cut-off term for FEV(1)/FVC and FVC. The data from the current study indicate that FEV(1)/ FEV(6) <73% and FEV(6) <82% predicted can be used as a valid alternative for the FEV(1)/FVC <70% and FVC <80% pred cut-off points for the detection of obstruction and restriction, respectively. The statistical analysis demonstrated very good, overall, agreement between the two categorisation schemes. For the spirometric diagnosis of airway obstruction (prevalence of 45.9%), FEV(1)/FEV(6) sensitivity and specificity were 94.4 and 93.3%, respectively; the positive and negative predictive values were 92.2 and 95.2%, respectively. For the spirometric detection of a restrictive pattern (prevalence of 14.9%), FEV(6) sensitivity and specificity were 95.9 and 98.6%, respectively; the positive and negative predictive values were 92.2 and 99.3%, respectively. This study demonstrates that forced expiratory volume in one second/forced expiratory volume in six seconds <73% and forced expiratory volume in six seconds <82% predicted, can be used as valid alternatives to forced expiratory volume in one second/forced vital capacity <70% and forced vital capacity <80% predicted, as fixed cut-off terms for the detection of an obstructive or restrictive spirometric pattern in adults.     

慢性阻塞性肺疾病患者血清抵抗素和瘦素水平及其与营养状况的关系

目的探讨慢性阻塞性肺疾病(COPD)患者血清抵抗素、瘦素水平及其与营养状况的关系。方法用酶联免疫吸附测定(ELISA)和放射免疫法检测57例稳定期COPD患者和31名健康对照者血清抵抗素、瘦素水平,分析相关因素。结果COPD患者血清抵抗素、瘦素水平[(2·1±1·2)、(0·65±0·41)μg/L]与对照组[(3·6±2·3)、(1·03±0·71)μg/L]比较差异均有统计学意义(P均<0·01)。COPD营养不良患者抵抗素、瘦素水平[(1·7±0·7)、(0·43±0·16)μg/L]显著低于非营养不良患者[(2·2±1·2)、(0·73±0·48)μg/L,P均<0·05]。COPD患者抵抗素与瘦素、第一秒用力呼气容积(FEV1)及FEV1/用力肺活量(FVC)显著正相关(r=0.426~0.531,P均<0·01),瘦素与体重指数(BMI)、胸围、腹围、抵抗素及FEV1/FVC显著正相关(r=0.371~0.580,P均<0·01)。结论COPD稳定期患者血清抵抗素、瘦素水平下降,合并营养不良时下降更显著。     

Reduced pulmonary function and its associations in type 2 diabetes: the Fremantle Diabetes Study

To determine whether diabetes is associated with reduced lung function, we studied 421 Anglo-Celt/European subjects, representing 20.5% of all patients with type 2 diabetes identified in an urban Australian catchment area of 120097 people. In addition to collection of detailed demographic and diabetes-specific data, spirometry was performed and forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), vital capacity (VC) and peak expiratory flow (PEF) measured. When expressed as a percentage of those predicted (%pred) for age, sex and height, the means of all spirometric measures were reduced by > or =9.5%. After controlling for smoking, age and gender in a linear regression model, HbA(1c) was not associated with any measure of lung function (P>0.13) but diabetes duration was significantly associated with FEV1(%pred) and PEF(%pred) (P< or =0.04) and had borderline associations with FVC(%pred) and VC(%pred) (P< or =0.064). In separate analyses controlling for smoking alone, age, body mass index (BMI), coronary heart disease (CHD) and retinopathy were independently and inversely associated with FVC(%pred), FEV1(%pred) and VC(%pred) (P<0.05). In sub-group analyses, these three spirometric measures were associated with BMI, CHD and diabetes duration in males, and age and BMI in females. Pulmonary function is reduced in type 2 diabetes. Diabetes duration seems a more important influence than glycaemic control, but obesity and vascular disease may also contribute.     

Importance of smoking index for assessing lung damage by lung function tests

A total of 89 smokers of age varying between 15-52 years were assessed for lung function forced vital capacity (FVC), forced expiratory volume in one second (FEV1) ratio of FEV1 and FVC as FEV1% and peak expiratory flow rate (PEFR), before smoking (BS) and 30 min after smoking (AS). All the above lung function tests were reduced in smokers in comparison to those of age-matched non-smokers. Further, when observed test values of lung function were tabulated according to smoking index (SI), it was noted that reduction of lung function increased with SI.     

Relationship between lung function and physical performance in disabled older women

BACKGROUND: Understanding the association between lung function and physical performance in disabled older women helps in determining the potential for prevention and treatment strategies to decrease disability. The aim of this study was to determine the association of lung function with objective and self-reported physical performance in community-dwelling disabled older women. METHODS: The Women's Health and Aging Study I consists of 1002 disabled community-dwelling women aged > or = 65. Of these women, 840 underwent spirometry with determination of forced expiratory volume in one second (FEV1) and forced vital capacity (FVC). Cross-sectional analyses included multivariate linear regression to assess the association between FEV1, FVC, FEV1/FVC, and the time to walk four meters after adjusting for confounders, including age, race, geriatric depression scale score, body mass index, muscle strength, osteoarthritis, smoking status, and cardiovascular disease. Multiple logistic regression was used to assess the association between FEV1, FVC, FEV1/FVC, and self-reported disability in physical performance. RESULTS: FEV1 was independently associated with time to walk 4 meters. For every 100 ml decrease in FEV1, there was a 0.15-second (95% confidence interval: 0.24 to 0.06) increase in time to walk 4 meters. There was an 8% increase in the prevalent odds of self-reported disability in physical performance for every 100 ml decrease in FEV1. FVC was also associated with physical performance measures. In contrast, FEV1/FVC was associated with objective but not subjective physical performance. CONCLUSION: Decreasing lung function is independently associated with decrements in objective and self-reported physical performance in disabled older women.     

Overweight and Obesity May Lead to Under-diagnosis of Airflow Limitation: Findings from the Copenhagen City Heart Study

Background: The prevalence of obesity has increased during the last decades and varies from 10-20% in most European countries to approximately 32% in the United States. However, data on how obesity affects the presence of airflow limitation (AFL) defined as a reduced ratio between forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) are scarce. Methods: Data was derived from the third examination of the Copenhagen City Heart Study from 1991 until 1994 (n = 10,135). We examine the impact of different adiposity markers (weight, body mass index (BMI), waist circumference, waist-hip ratio, and abdominal height) on AFL. AFL was defined in four ways: FEV1/FVC ratio < 0.70, FEV1/FVC ratio < lower limit of normal (LLN), FEV1/FVC ratio <0.70 including at least one respiratory symptom, and FEV1/FVC ratio < LLN and FEV1% of predicted < LLN. Results: All adiposity markers were positively and significantly associated with FEV1/FVC independent of age, sex, height, smoking status, and cumulative tobacco consumption. Among all adiposity markers, BMI was the strongest predictor of FEV1/FVC. FEV1/FVC increased with 0.04 in men and 0.03 in women, as BMI increased with 10 units (kg?·?m-2). Consequently, diagnosis of AFL was significantly less likely in subjects with BMI ≥ 25 kg?·?m-2 with odds ratios 0.63 or less compared to subjects with BMI between 18.5–24.9 kg?·?m-2 when AFL was defined as FEV1/FVC < 0.70. Conclusion: High BMI reduces the probability of AFL. Ultimately, this may result in under-diagnosis and under-treatment of COPD among individuals with overweight and obesity.     

Changes in pulmonary function in patients with ulcerative colitis

OBJECTIVES: Information on the occurrence and frequency of pulmonary involvement in patients with ulcerative colitis (UC) is inconsistent. Some authors reported pulmonary impairment with UC by standard pulmonary function tests (PFTs) and documented a reduced diffusing capacity for carbon monoxide (DLCO) especially in patients with active disease, whereas others could not detect differences in routine PFTs between UC patients and controls. AIM: The aim of this prospective study was to determine the frequency and type of pulmonary dysfunction in patients with UC with respect to disease activity. Furthermore, to evaluate the influence of smoking, nutritional status, sputum cytology and sulphasalazine therapy on PFT parameters. PATIENTS AND METHODS: Twenty-six patients with UC (20 with active disease, 6 inactive) and 16 age and sex matched healthy controls were investigated with respect to the following pulmonary function tests, forced vital capacity (FVC), forced expiratory volume in the 1s (FEV(1)%) and their ratio (FEV(1)/FVC) and forced expiratory flow 25-75% (FEF25-75%) as well as oxygen saturation. For UC patients, colonoscopy and biopsy were done. Disease activity was assessed by Truelove index for UC. Induced sputum was sampled for cytology. Smoking habit, body mass index (BMI) and medications were recorded. RESULTS: Fifteen out of 26 patients with UC (57.6%) exhibited at least one pathological pulmonary function test (<80% of predicted value). Small airway obstruction was reported in the 15 patients, restrictive dysfunction in 30.7% and obstructive dysfunction in 11.5%. The impairment of PFTs was significant and more pronounced in patients with active disease, FVC (-14% of predicted), FEV(1) (-9% of predicted) and FEF25-75% (-32% of predicted), P<0.01, 0.05 and 0.01, respectively. There was no significant influence of smoking and medications on PFTs. CONCLUSIONS: UC patients show significantly decreased lung function tests in comparison to healthy controls. The impairment in active disease exceeded that during the remission. Early recognition is important, as they can be strikingly steroid responsive.     

支气管哮喘合并胃食管反流病相关危险因素分析

目的探讨支气管哮喘合并胃食管反流病（GERD）的相关危险因素,为预防及治疗提供理论依据。 方法回顾性收集自2013年1月至2018年8月在新疆维吾尔自治区人民医院呼吸科就诊的支气管哮喘合并GERD患者187例及单纯支气管哮喘者192例临床资料,统计方法比较两组临床特点,分析哮喘合并GERD相关危险因素。 结果两组患者年龄、性别、过敏史、高血压病史、冠心病病史、糖尿病病史、饮酒史等差异无统计学意义（P＞0.05）;两组患者吸烟史、体重指数（BMI）、哮喘家族史、第一秒末用力呼气量（FEV1）、FEV1/用力肺活量（FVC）、最大呼气流量（PEF）内急性发作次数等有差异性,并差异有统计学意义（P＜0.05）。多因素Logistic回归分析结果显示,高BMI、吸烟、PEF、既往12月内急性发作次数是哮喘合并GERD的独立危险因素（P＜0.05）。 结论高BMI、吸烟、PEF、既往12月内急性发作次数是哮喘合并GERD的危险因素,改善肺功能、积极减重、戒烟,有望预防和减少GERD的发生。     

Does negative expiratory pressure influence performances of spirometry in older patients?

The aim of this study is to assess the influence of the negative expiratory pressure (NEP) technique on the performance of maximal expiratory manoeuvre in elderly patients. Firstly, the authors studied how NEP (at 5 and 10 cmH2O, NEP5 and NEP10) influences forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) in 60 young healthy volunteers, in order to assess the fluctuations of the method. In the second part of the study, 65 successive elderly inpatients (>70 yrs old) were examined. In this group, 15 elderly patients were unable to perform the manoeuvre, 27 had a normal function, 14 had a lung function with obstructive pattern and nine with restrictive pattern. In young subjects, FVC during NEP5 and NEP10 compared to baseline values was 101+/-5%, and 103+/-5%, respectively, and FEV1 was 100+/-4% and 101+/-5%, respectively. In elderly patients with normal function, FVC during NEP5 and NEP10 compared to baseline values was 99+/-14% and 109+/-23%, respectively, and FEV1 was 97+/-9% and 104+/-13%, respectively. There were no relevant effects of the NEP application on FVC or FEV1 values in elderly patients with an obstructive or restrictive pattern. In elderly patients, the use of the negative expiratory pressure technique during maximal expiratory manoeuvres provides little complementary information compared to a classical manoeuvre. The negative expiratory pressure technique did not modify the initial diagnosis when compared with the classical manoeuvre.     

Respiratory consequences of light and moderate smoking in young adults in Chile.

OBJECTIVE: To assess the association between smoking and respiratory symptoms, lung function and bronchial hyperresponsiveness (BHR) in young adults in Chile. SETTING: Selected sample of 1232 subjects aged 22-28 years. DESIGN: In this cross-sectional study, the outcome measures were: respiratory symptoms, forced expiratory volume in one second (FEV1), forced vital capacity (FVC), forced expiratory flow between 25% and 75% (FEF25-75), FEV1/FVC and BHR. RESULTS: Among the 1232 subjects, 67.7% of the men and 49.4% of the women were smokers; the median cigarettes smoked per day was four for men and three for women. Smoking was associated with wheezing, waking up with a cough, breathlessness following exercise and persistent cough, with odds ratios (OR) between 1.94 (95% CI 1.41-2.66) and 3.12 (95% CI 2.21-4.40) among those smoking > or = 5 cigarettes per day, compared to non-smokers. Smoking < 5 cigarettes was significantly associated with wheezing and waking up with a cough. Smokers had a lower FEV1/FVC than non-smokers by approximately 0.8%. Smoking was not associated with FEV1, FEF25-75 or BHR status. CONCLUSIONS: This study highlights the early effects of smoking on respiratory symptoms. It could help governments in Latin America take vigorous action to deter young people from starting smoking.     

Pleuropulmonary complications of esophageal variceal sclerotherapy with absolute alcohol

BACKGROUND: Esophageal variceal sclerotherapy (EVS) is an effective means of controlling variceal hemorrhage. However, it causes a wide variety of local and systemic complications. The present study was performed to document pleuropulmonary complications of EVS with absolute alcohol. METHODS: Twenty-six patients of portal hypertension of different etiologies were subjected to EVS with absolute alcohol. Baseline arterial blood gas analysis (PaO2, PaCO2, pH, HCO3, SaO2), chest X-ray and pulmonary function tests (forced expiratory volume at 1 s (FEV1), forced expiratory vital capacity (FVC), FEV1/FVC, maximum mid-expiratory flow rate (MMFR), and peak expiratory flow rate (PEFR)) were performed 4-6 h before the first session of EVS. These investigations were repeated within 24 h of EVS. Patients were asked to maintain a symptom diary and to record symptoms such as fever, chest pain, dysphagia and dyspnea during the study period. RESULTS: Ten patients (38.46%) had chest pain and four patients (15.68%) had fever after sclerotherapy. Eight patients (30.54%) complained of dyspnea and six patients (23.08%) developed pleural effusion. There was a significant decline in FVC and FEV1 after EVS as compared with baseline values. However, FEV1/FVC ratio, MMFR and PEFR did not have any significant change. CONCLUSIONS: Chest pain (38.46%), dyspnea (30.54%) and fever (15.68%) were the common symptoms after EVS while chest X-ray showed pleural effusion in 23.08%. Pulmonary function tests revealed a significant decline in FEV1 and FVC without change in FEV1/FVC ratio after EVS, suggesting a restrictive type of defect.     

Maternal and personal cigarette smoking synergize to increase airflow limitation in adults

Susceptibility of the lungs to cigarette smoke is poorly understood. It is not known whether maternal smoking increases chronic obstructive pulmonary disease (COPD) risk. In 1998 we reported an inverse association between maternal smoking (prerecorded) and FEV(1) in adults. Because FEV(1) and FVC are strongly correlated, it is unclear whether the association in question reflects a link with lung volume, airflow limitation, or both. We extended our original analysis to investigate whether maternal and personal smoking synergize to increase airflow limitation. We estimated residual FEV(1) to express FEV(1) variation that was not associated with FVC. Maternal smoking was inversely associated with FVC and FEV(1) irrespective of personal smoking. It was inversely associated with FEV(1)/FVC, forced midexpiratory flow rates (FEF(25-75) [mean forced expiratory flow during the middle half of the FVC], FEF(25-75)/FVC), and residual FEV(1) in current smokers but not in never or former smokers (heterogeneity p = 0.016, 0.024, 0.021, and 0.016, respectively). We tested the clinical relevance of findings in ever smokers without asthma: 10 cigarettes/day maternal smoking increased prevalent COPD by 1.7 (95% confidence interval: 1.2-2.5) after adjustment for covariates. Maternal smoking impairs lung volume irrespective of personal smoking and appears to synergize with personal smoking to increase airflow limitation and COPD.     

What is a 'restrictive' defect?

We studied 211 sets of pulmonary function data to evaluate spirographic findings in patients with restrictive defects, and to determine the significance of the spirographic interpretation of restriction. A combination of clinical and body plethysmographic data was used as the standard for the diagnosis of restriction. Restriction was diagnosed spirographically when forced vital capacity (FVC) was low and the ratio of one-second forced expiratory volume (FEV1) to FVC (FEV1/FVC%) was normal. With these criteria, using 70% as the lower limit of normal for FEV1/FVC%, the spirogram had a 93% sensitivity and an 82% specificity for the detection or exclusion of a restrictive defect. Ten percent of patients with pure obstructive defects by clinical and plethysmographic criteria showed a restrictive defect on the spirogram. Combined obstructive and restrictive defects were rare; in these cases the spirogram showed a restrictive defect but missed the obstructive component.     

Influence of socioeconomic status on lung function and prediction equations in Indian children

The present study was carried out to assess the influence of socioeconomic status on lung functions and to suggest prediction equations for Indian children. For this purpose, 2,616 normal, healthy schoolchildren aged between 5-15 years were recruited. Boys were classified into three groups, i.e., high-income (HIG), middle-income (MIG), and low-income (LIG), while girls were classified into HIG and LIG groups, based on socioeconomic status (SES). Height, weight, chest circumference, body surface area (BSA), fat-free mass (FFM), and body fat were assessed. Forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC), FEV1/FVC ratio, and peak expiratory flow rate (PEFR) were measured. The results, before and after adjustment of physical characteristics, showed that anthropometry, body composition, and lung functions were significantly higher in HIG compared to MIG and LIG children, while in girls, no differences were observed in physical characteristics after adjustments. Multiple linear regression equations were developed to predict FEV1, FVC, and PEFR, using independent variables like age, height, fat-free mass, and SES. It is opined that these equations could be used as Indian reference equations for healthy children based on the SES.     

Obstructive and restrictive lung disease and functional limitation: data from the Third National Health and Nutrition Examination

OBJECTIVE: To determine functional limitations in adults with obstructive or restrictive lung disease or respiratory symptoms. DESIGN: Cross-sectional study. SUBJECTS: Adult participants in phase 2 of the Third National Health and Nutrition Examination Survey, 1991-94. METHODS: We classified subjects using spirometric criteria into the following mutually exclusive categories using the forced expiratory volume in 1 s (FEV1), the forced vital capacity (FVC), the FEV1/FVC ratio and the presence of respiratory symptoms: severe obstruction, moderate obstruction, mild obstruction, respiratory symptoms only, restrictive lung disease and no lung disease. We developed regression models to predict functional limitations (unable to walk a quarter of a mile, unable to lift 10 pounds, needs help with daily activities) that controlled for age, race, sex, education, smoking status, body mass index and comorbid conditions. RESULTS: Severe and moderate obstruction were associated with an increased risk of being unable to walk a quarter of a mile [odds ratio (OR) 8.4, 95% confidence interval (CI) 3.6, 19.9 and OR 2.4, 95% CI 1.4, 4.0]. Restrictive lung disease and the presence of respiratory symptoms in the absence of lung function impairment were also associated with an increased risk of this outcome (OR 2.8, 95% CI 1.4, 5.6 and OR 2.8, 95% CI 2.0, 3.9). Similar results were obtained for the outcomes of being unable to lift 10 pounds or needing help with daily activities. CONCLUSIONS: The presence of obstructive or restrictive lung disease, or respiratory symptoms in the absence of lung function impairment is associated with increased functional impairment.     

Associations of measures of lung function with insulin resistance and Type 2 diabetes: findings from the British Women’s Heart and Health Study

Aims/hypothesis The aim of this study was to assess the associations of lung function with insulin resistance and Type 2 diabetes.Methods We did a cross-sectional study of 3911 women who were 60 to 79 years old from 23 British towns, assessing the association of measures of lung function with insulin resistance (based on fasting insulin and glucose concentrations) and Type 2 diabetes (World Health Organisation diagnostic criteria).Results Forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) were inversely associated with insulin resistance and prevalence of Type 2 diabetes. In age-adjusted analyses, the homeostasis model assessment (HOMA) score (insulin resistance) decreased by 5% (95% CI: 2–7%) for a one standard deviation increase in log FEV1 and by 8% (95% CI: 6–10%) for a one standard deviation increase in log FVC. With additional adjustment for height, smoking, BMI, waist-to-hip ratio, physical activity, white cell count, adult social class, childhood social class and respiratory medication, these associations attenuated to 3% (95% CI: 1 to 5%) and 5% (95% CI: 3 to 8%). The fully adjusted odds ratio for diabetes prevalence was 0.85 (95% CI: 0.74–0.98) for a one standard deviation increase in log FEV1 and 0.80 (95% CI: 0.70–0.92) for a one standard deviation increase in log FVC. Forced expiratory flow in the central period of FVC was not associated with insulin resistance or diabetes.Conclusions/interpretation Lung function measures which predominantly reflect lung volume are inversely associated with insulin resistance and Type 2 diabetes. These associations could reflect childhood exposures which affect lung growth and also programme insulin resistance.Abbreviations FEV1 Forced expiratory volume in 1 second - FVC forced vital capacity - FEF25–75 forced expiratory flow in the central period of forced vital capacity - HOMA Homeostasis model assessment - WHO World Health Organization     

Body composition in patients with chronic hypercapnic respiratory failure

STUDY OBJECTIVE: To evaluate the contribution of body composition measurements to clinical assessment in patients on home nasal positive-pressure ventilation for chronic hypercapnic respiratory failure (CHRF), and their relationship to respiratory impairment. METHODS: Patients with CHRF (restrictive lung disease (RLD), n=37; chronic obstructive pulmonary disease (COPD), n=19), during elective yearly evaluations underwent pulmonary function testing (forced expiratory volumes, arterial blood gases, maximal inspiratory and expiratory pressure (PI(max) or PE(max))), and bioelectrical impedance analysis to determine fat-free mass (FFM) index (kg/m(2)) and body fat mass index. RESULTS: When compared with age- and sex-matched healthy controls, RLD patients (OR 5.5, CI 1.9-15.6, P<0.002) and COPD (OR 5.2, CI 1.1-24.9, P=0.04) were significantly more likely to have a low FFM index. Roughly one-half of patients with RLD and one-third with COPD had abnormally low FFM index. Estimation of nutritional status by body mass index (BMI) alone clearly underestimated the prevalence of FFM index depletion. Muscle mass assessed by FFM index explained 26% of variance of PI(max) (P<0.001) and 27% of that of PE(max) (P<0.001). CONCLUSION: BMI alone clearly underestimated FFM depletion, and presence of a very high body fat mass index. Indeed, normal or high BMI can be associated with FFM depletion. Because of its relationship to respiratory muscle strength, an assessment of FFM appears to be valuable in CHRF.     

Spirometric reference values for the 6-s FVC maneuver

STUDY OBJECTIVES: The guidelines of the National Lung Health Education Program for COPD screening proposed a shorter FVC maneuver (forced expiratory volume at 6 s of exhalation [FEV(6)]). Although reference values for FEV(6) are available from the third National Health and Nutrition Examination Survey, forced expiratory flow between 25% and 75% of FVC (FEF(25-75%)) reference values for the shorter 6-s maneuver are not available and are needed. In particular, calculation of largest observed volume during the first 6 s of an FVC maneuver (FVC(6)), from a shortened FVC maneuver, is necessary because the FEF(25-75%) measurement is based on a percentage of FVC or, for a shorter maneuver, FVC(6). DESIGN: We reanalyzed the raw volume-time curves from the third National Health and Nutrition Examination Survey to calculate FVC(6), forced expiratory volume at 0.5 s of exhalation, forced expiratory volume at 3 s of exhalation, ratio of the FEV(1) to largest observed volume during the first 6 s of an FVC maneuver expressed as a percentage (FEV(1)/FEV(6)%), and forced expiratory flow between 25% and 75% of the largest observed volume during the first 6 s of an FVC maneuver (FEF(25-75%6)) in addition to the previously reported values for FEV(1), FEV(6), and FEV(1)/FEV(6)%. PATIENTS OR PARTICIPANTS: Using the same normal, asymptomatic, nonsmoking reference population from a previous study, reference values for these parameters were derived from best values. RESULTS: A total of 2,261 white, 2,564 African-American, and 2,666 Mexican-American subjects aged 8 to 80 years were included in the analysis. Fifty-four subjects from the previous study were not included due to missing raw volume-time curves. CONCLUSIONS: These reference values, utilizing the FVC(6), provide investigators with the means of evaluating the relative merits of using the shorter FVC maneuver as a surrogate for the traditional FVC. They are needed particularly for calculating FEF(25-75%), as statistically significant differences were observed between the FEF(25-75%) and FEF(25-75%6).     

Risk factors for airflow obstruction in recipients of bone marrow transplants

Obstructive lung disease is a complication of bone marrow transplantation. To identify risk factors we analyzed pulmonary function tests of 281 adult patients 1 year after marrow transplantation. The forced expiratory volume at 1 second divided by the forced vital capacity (FEV1/FVC) was used to measure airflow rates. Factors associated with a lower year-1 FEV1/FVC (%) included increased age (p less than 0.0001), male gender (p = 0.02), cigarette smoking (p = 0.01), lower FEV1/FVC before transplantation (p less than 0.0001), HLA-nonidentical grafts (p = 0.001), chronic graft-versus-host disease (p = 0.0002), and immunosuppressive therapy with methotrexate (p = 0.01). There was no significant association between the year-1 FEV1/FVC and underlying disease, dose of conditioning irradiation, or development of acute graft-versus-host disease. Linear multivariate regression analysis, after controlling for the FEV1/FVC before transplantation, shows both chronic graft-versus-host disease and administration of methotrexate independently associated with decrements in the year-1 FEV1/FVC. The combined occurrence of chronic graft-versus-host disease and methotrexate also was strongly associated with decreases in the year-1 FEV1/FVC, indicating an interaction of these risk factors.