Determinants of respiratory symptom development in patients with chronic airflow obstruction

BACKGROUND: This study was undertaken to identify the determinants of respiratory symptom development in patients with chronic airflow obstruction (CAO). METHODS: Categories of symptomatic and asymptomatic CAO were defined using questionnaire responses and spirometric results. We analyzed data obtained as part of the second South Korean National Health and Nutrition Examination Survey (Korean NHANES II). RESULTS: Among 187 patients with CAO, 69 had no respiratory symptoms. CAO patients with symptoms were significantly older than those without symptoms (P=0.026), and hypertension was more common among symptomatic CAO patients than among asymptomatic CAO patients (P=0.005). According to questionnaire responses, symptomatic CAO patients had more difficulty in walking or lifting (P<0.001), required more help with personal care (P=0.01), and had poorer general health than asymptomatic CAO patients (P=0.008). Symptomatic CAO patients had higher fasting blood glucose levels than asymptomatic CAO patients (P=0.028). Symptomatic CAO patients had significantly lower forced expiratory volume in 1s (FEV1) (P=0.001), forced vital capacity (FVC) (P=0.008), and a ratio of FEV1/FVC than asymptomatic CAO patients (P<0.001). Statistically significant predictors of symptom development were as follows: age (odds ratio (OR) 1.04, P=0.028), hypertension (OR 4.41, P=0.008), fasting blood glucose (OR 1.02, P=0.034), FEV1 (OR 0.07, P=0.002), FVC (OR 0.08, P=0.009), FEV1/FVC (OR 0.00, P=0.001). Multiple logistic regression analyses revealed two independent factors associated with symptom development: FEV1/FVC (OR 0.001, P=0.002) and hypertension (OR 5.95, P=0.005). CONCLUSIONS: In CAO, respiratory symptom development is significantly associated with low FEV1/FVC and the presence of hypertension.     

Factors associated with improvement in breathing capacity during exercise in patients with chronic obstructive pulmonary disease

OBJECTIVES: The aim of this study was to explore the relationship between resting pulmonary function indices and the ratio of minute ventilation at peak exercise to the maximal voluntary ventilation (VEmax/MVV) and to determine whether an improvement in breathing capacity during exercise (i.e. VEmax/MVV > 1) is associated with greater exercise capacity in patients with COPD. METHODOLOGY: The results of pulmonary function tests and incremental, symptom-limited cardiopulmonary exercise testing in 84 patients with predominantly moderate to severe COPD were reviewed. Multiple linear regression analysis was applied to determine the relationship of VEmax/MVV with selected independent variables at rest. Multiple logistic regression was used to determine significant predictors of VEmax/MVV 1. RESULTS: FEV1/FVC and inspiratory capacity (IC) were the only variables among resting pulmonary function indices that were significant independent determinants of VEmax/MVV and the stepwise analysis generated the following equation: VEmax/MVV = (-1.05E-02 x FEV1/FVC) + (0.15 x IC) + 1.28; r= 0.701, P < 0.001. Using multiple logistic regression with VEmax/MVV 1 as a dependent categorical variable, FEV1/FVC was the only significant predictor among resting pulmonary indices of a VEmax/MVV ratio of > 1 (Odds ratio 0.93, 95%CI 0.89, 0.97). There was a significant association between VEmax/MVV and peak oxygen uptake (VO2max) after adjusting for FEV1 (r = 0.66, P < 0.001). If the categorical variable of VEmax/MVV ( 1) was used instead of a continuous variable, a significant association with VO2max remained after adjusting for FEV1 (r = 0.60, P < 0.001). CONCLUSIONS: Among resting pulmonary function indices, the FEV1/FVC ratio is the best determinant of an improvement in breathing capacity during exercise in COPD patients. After adjusting for FEV1, an improvement in breathing capacity during exercise is associated with significantly higher exercise capacity.     

Pulmonary function after exposure to the World Trade Center collapse in the New York City Fire Department

RATIONALE: On September 11, 2001, the World Trade Center collapse created an enormous urban disaster site with high levels of airborne pollutants. First responders, rescue and recovery workers, and residents have since reported respiratory symptoms and developed pulmonary function abnormalities. OBJECTIVES: To quantify respiratory health effects of World Trade Center exposure in the New York City Fire Department. MEASUREMENTS: Longitudinal study of pulmonary function in 12,079 New York City Fire Department rescue workers employed on or before 09/11/2001. Between 01/01/1997 and 09/11/2002, 31,994 spirometries were obtained and the FEV(1) and FVC were analyzed for differences according to estimated World Trade Center exposure intensity. Adjusted average FEV(1) during the first year after 09/11/2001 was compared with the 5 yr before 09/11/2001. Median time between 09/11/2001 and a worker's first spirometry afterwards was 3 mo; 90% were assessed within 5 mo. MAIN RESULTS: World Trade Center-exposed workers experienced a substantial reduction in adjusted average FEV(1) during the year after 09/11/2001 (372 ml; 95% confidence interval, 364-381 ml; p < 0.001) This exposure-related FEV(1) decrement equaled 12 yr of aging-related FEV(1) decline. Moreover, exposure intensity assessed by initial arrival time at the World Trade Center site correlated linearly with FEV(1) reduction in an exposure intensity-response gradient (p = 0.048). Respiratory symptoms also predicted a further FEV(1) decrease (p < 0.001). Similar findings were observed for adjusted average FVC. CONCLUSIONS: World Trade Center exposure produced a substantial reduction in pulmonary function in New York City Fire Department rescue workers during the first year after 09/11/2001.     

支气管肺泡灌洗联合无创正压通气对矽肺患者肺功能、血气分析及6min步行试验的影响

目的：研究支气管肺泡灌洗联合无创正压通气对矽肺患者肺功能、血气分析及6min步行试验的影响。方法：选择自2010年2月至2014年2月于本院呼吸内科就诊的矽肺患者76例,随机分为研究组与对照组各38例,两组患者均接受平喘化痰以及无创正压通气治疗,研究组同时行支气管肺泡灌洗治疗方案。比较两组患者治疗前后肺功能(FEV1、FVC、FEV1占正常预计值%)、血气分析(PaO2、PaCO2)以及6min步行试验的差异。结果：比较两组治疗前后结果发现肺功能指标FEV1治疗后均提升且研究组(P<0.001)较对照组(P=0.011)提升更明显；FVC结果也相似；FEV1占正常预计值%均显著提升(P<0.001)； 血气分析PaO2值研究组(P<0.001)比对照组(P=0.029)显著升高；PaCO2值均降低(P<0.001)；6min步行距离研究组(P<0.001)较对照组(P=0.011)显著增加。结论：对矽肺患者行支气管肺泡灌洗联合无创正压通气治疗能改善矽肺患者的肺功能、血气指标及患者的运动耐量。     

Acute and chronic pulmonary function changes in allergic bronchopulmonary aspergillosis.

Pulmonary functions of patients with allergic bronchopulmonary aspergillosis were studied during an acute episode (n = 6); during a mean follow-up period of 44 months (range four months--14.8 years) (n = 16); and for any correlation between duration of ABPA and asthma with the total lung capacity (helium dilution), 1 second forced expiratory volume (FEV1), vital capacity, 1 second forced expiratory volume-forced vital capacity ratio (FEV1:FVC per cent) and diffusing capacity of carbon monoxide (DL:CO) (single breath) for the entire group (n = 22). All patients were treated with corticosteroids (intermittent or continuous) and bronchodilators. For the 16 patients, slopes using linear regression analysis were determined from the function as per cent predicted versus time in months from diagnosis and then analyzed for significance. Significant functional loss was shown in three of 16 patients for FEV1, two of 16 patients for vital capacity, one of 16 patients for FEV1:FVC per cent, none of 10 patients for DL:CO and one of 10 patients for total lung cital capacity, FEV1:FVC per cent and the duration of asthma or allergic bronchopulmonary aspergillosis was found by multiple regression analysis correcting for age and smoking (mean 4.24 years; range 0.3 to 14.8 years). Roentgenographic criteria and blood eosinophilia were used to define a "flare" of allergic bronchopulmonary aspergillosis. The six patients during a flare showed a significant reduction in total lung capacity (P less than 0.001), vital capacity (P less than 0.05), FEV1 (P less than 0.01) and DL:CO (P less than 0.001) which uniformly returned to baseline values during steroid therapy. The FEV1:FVC per cent remained unaltered. These findings, contrary to suggestions in the literature, indicate that in the majority of our patients there was no significant progressive functional deterioration after diagnosis. However, during acute episodes of allergic bronchopulmonary aspergillosis, transient reduction of volumes and DL:CO were uniformly present.     

Kurtosis and skewness of density histograms on inspiratory and expiratory CT scans in smokers

The aim of this study is to evaluate the relationship between lung function and kurtosis or skewness of lung density histograms on computed tomography (CT) in smokers. Forty-six smokers (age range 46?81 years), enrolled in the Lung Tissue Research Consortium, underwent pulmonary function tests (PFT) and chest CT at full inspiration and full expiration. On both inspiratory and expiratory scans, kurtosis and skewness of the density histograms were automatically measured by open-source software. Correlations between CT measurements and lung function were evaluated by the linear regression analysis. Although no significant correlations were found between inspiratory kurtosis or skewness and PFT results, expiratory kurtosis significantly correlated with the following: the percentage of predicted value of forced expiratory volume in the first second (FEV(1)), the ratio of FEV(1) to forced vital capacity (FVC), and the ratio of residual volume (RV) to total lung capacity (TLC) (FEV(1)%predicted, R = -0.581, p < 0.001; FEV(1)/FVC, R = -0.612, p < 0.001; RV/TLC, R = 0.613, p < 0.001, respectively). Similarly, expiratory skewness showed significant correlations with PFT results (FEV(1)%predicted, R = -0.584, p < 0.001; FEV(1)/FVC, R = -0.619, p < 0.001; RV/TLC, R = 0.585, p < 0.001, respectively). Also, the expiratory/inspiratory (E/I) ratios of kurtosis and skewness significantly correlated with FEV(1)%predicted (p < 0.001), FEV(1)/FVC (p < 0.001), RV/TLC (p < 0.001), and the percentage of predicted value of diffusing capacity for carbon monoxide (kurtosis E/I ratio, p = 0.001; skewness E/I ratio, p = 0.03, respectively). We conclude therefore that expiratory values and the E/I ratios of kurtosis and skewness of CT densitometry reflect airflow limitation and air-trapping. Higher kurtosis or skewness on expiratory CT scan indicates more severe conditions in smokers.     

Pulmonary function of U.S. coal miners related to dust exposure estimates.

This study of 7,139 U.S. coal miners used linear regression analysis to relate estimates of cumulative dust exposure to several pulmonary function variables measured during medical examinations undertaken between 1969 and 1971. The exposure data included newly derived cumulative dust exposure estimates for the period up to time of examination based on large data bases of underground airborne dust sampling measurements. Negative associations were found between measures of cumulative exposure and FEV1, FVC, and the FEV1/FVC ratio (p less than 0.001). In general, the relationships were similar to those reported for British coal miners. Overall, the results demonstrate an adverse effect of coal mine dust exposure on pulmonary function that occurs even in the absence of radiographically detected pneumoconiosis.     

Changes in spirometry during consecutive admissions for infective pulmonary exacerbations in adolescent and adult cystic fibrosis.

Changes in spirometry during consecutive admissions for treatment of pulmonary infective exacerbations were studied in 45 patients (24 males, 21 females) with cystic fibrosis (CF) who had required five or more such admissions. Over the overall study period there was a mean (SD) decline in FEV1 of -112.1 (188.0) ml yr-1 (P less than 0.001) and in FVC of -47.9 (82.4) ml yr-1 (P less than 0.001). FEV1 and FVC increased during each admission with treatment; however, the magnitude of this change became less over consecutive admissions by a mean value of -33.3 ml (45.0) (P less than 0.001) for FEV1, and -26.0 (72.2) ml (P less than 0.05) for FVC. In the majority of patients that died or underwent transplantation, FEV1 at the time of the last admission did not rise above 800 ml despite full treatment.     

Serum amino acids in relation to nutritional status, lung function and energy intake in patients with advanced pulmonary disease

Malnutrition, hypoxia and energy deficit may affect protein metabolism. We wanted to evaluate the cross-sectional association between serum amino acids and fat-free mass in a group of hypoxic patients. We also wanted to explore, in the same group of patients, whether the blood amino-acid pattern could possibly be influenced by differences in lung function and energy intake. Serum amino acids were measured in 71 hypoxic underweight and normal-weight patients with advanced pulmonary disease and related to the fat-free-mass index, arterial oxygen (PaO2) and carbon dioxide tension (PaCO2), forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1) and energy intake. Only one amino acid (aspartic acid) remained significantly correlated to the fat-free-mass index after adjustments for age and sex (beta = -0.30, P=0.011). None of the amino acids were significantly correlated to PaO2 but alanine was significantly negatively correlated to PaCO2 (beta = -0.46, P<0.001), phenylalanine to FVC1 (beta = 0.52, P=0.001) and tyrosine to FVC (beta = 0.36, P=0.008). Citrulline and tryptophan were significantly correlated to energy intake (beta = 0.32, P=0.008; beta=0.37, P=0.009 respectively). In conclusion, there was no convincing association between fat free mass and serum amino acids. The negative effect of hypercapnia and reduced lung function on some serum amino acids was suggested and some amino acids were sensitive to reduced energy intake.     

Lung health in Alberta farmers.

SETTING: A study conducted in the rural areas of two counties in east-central Alberta, Canada. OBJECTIVE: To investigate the relationship between lung health and dust exposure in farmers. DESIGN: A cross-sectional study of 781 farmers growing grain crops and raising livestock. Measurements included a questionnaire on respiratory symptoms, smoking habits and occupation, skin prick tests using common aeroallergens, and spirometry. RESULTS: Immediate skin reactivity to common aeroallergens was less prevalent in farmers with higher reported intensity of dust exposure. Respiratory symptoms suggestive of bronchitis had a significant dose-response relationship with the reported intensity of dust exposure. Respiratory symptoms consistent with bronchial responsiveness were significantly positively associated with cumulative dust exposure. There was a significant positive association between a physician's diagnosis of bronchitis and intensity of dust exposure. FEV1 and FEV1/FVC were significantly negatively associated with cumulative dust exposure. Ten years of exposure to a moderate dust level was associated with a deficit of 43 ml in the FEV1 and a deficit of 0.44% in the FEV1/FVC. CONCLUSIONS: Despite evidence of worker selection related to dust exposure, these farmers experienced respiratory symptoms, respiratory conditions, and reduced lung function associated with reported occupational dust exposure.     

Association between arterial stiffness and pulmonary function in hypertensive patients

Arterial stiffness, assessed by cardio-ankle vascular index (CAVI), is clinically used to assess arteriosclerosis. Recently, pulmonary age, as determined by pulmonary function test, has been proposed by the Japanese Respiratory Society as a diagnostic measure for chronic obstructive pulmonary disease (COPD). This study aims to examine the association between CAVI and pulmonary function and to elucidate the correlation between vascular stiffness and pulmonary age in hypertensive patients. We enrolled a total of 45 hypertensive patients (70±9 years) who had been taking antihypertensive medications for at least 1 year. Pulmonary function was measured by the percentage of predicted forced vital capacity (FVC) and the ratio of forced expiratory volume in 1?s (FEV(1)) to FVC (FEV(1)/FVC ratio). Pulmonary age was determined by the equation proposed by the Japanese Respiratory Society. CAVI was measured at the same clinic visit. In the simple correlation analysis CAVI correlated with the FEV(1)/FVC ratio (r=-0.399, P=0.007) and pulmonary age (r=0.559, P<0.001). Multiple linear regression analysis revealed that CAVI was independently associated with FEV(1)/FVC ratio (β=-0.418, P=0.014) and pulmonary age (β=0.514, P=0.002). In addition, CAVI was significantly higher in patients with increased pulmonary age (9.4±1.4) than in those with normal pulmonary age (8.4±0.9) (P=0.011). The present study indicates that an increased CAVI is independently associated with reduced pulmonary function and increased pulmonary age. Hypertensive patients with high CAVI may need to be monitored for the progression of COPD.     

慢性阻塞性肺疾病不同病程肺功能动态改变特点和机制的研究

目的　探讨慢性阻塞性肺疾病（COPD）急性加重期和稳定期肺功能的动态改变特点和机制。方法　对30例COPD患者分别于急性加重期和稳定期进行Borg气急指数评估、肺通气功能检测、肺容量检测、体积描记法总气道阻力（Rtot）测定和呼吸阻抗、呼吸阻力检测。结果　Borg气急指数稳定期较急性加重期显著下降（P〈0．001）。通气功能测定参数FVC、FVC／pre、FEVI、FEVI／pre和FEV1／FVC稳定期较急性加重期显著增加（P均〈0．05）。肺容量检测参数深吸气量（IC）稳定期较急性加重期显著增加（P〈0．001）,胸腔内气体容积（ITGV）和残气量（RV）稳定期较急性加重期显著下降（P均〈0．05）。Rtot稳定期较急性加重期显著下降（P〈0．01）。IOS测定参数共振频率（Fres）、呼吸总阻抗（Z5）、总气道阻力（R5）、中央气道阻力（R20）和外周气道阻力（R5-R20）稳定期较急性加重期显著下降（P均〈0．05）,5Hz时呼吸电抗（X5）稳定期较急性加重期显著增高（P〈0．001）。通气功能检测参数中FEV-改善率最高,肺容量检测IC改善率最高,呼吸阻抗和呼吸阻力检测R5—R20和X5改善率较高。IC、RV和ITGV稳定期较急性加重期的改善值与FVC的改善值显著相关（P均〈0．05）,IC和RV稳定期的改善值与FEV-的改善值显著相关。Z5、R5、R5-R20、X5和Fres稳定期的改善值与通气功能参数FVC、FEV-和FEV-／FVC的改善值显著相关（P均〈0．05）。结论 COPD急性加重期较稳定期肺功能显著下降,肺过度充气和外周气道阻力增加是急性加重期肺功能恶化的主要原因。     

A comparative efficacy of oral prednisone with intramuscular triamcinolone in acute exacerbation of asthma

Corticosteroids are recommended for emergency management of an asthmatic attack. This study was designed to compare the effectiveness of oral and intramuscular steroid on spirometric results in acute asthma. We performed a randomized trial involving 88 adults, aged 15-70 years, with acute exacerbation of asthma requiring treatment with steroids. All had been treated with standard bronchodilator regimens and then received oral prednisone, 40 mg/day for 7 days, or 40 mg/day intramuscular triamcinolone long acting (LA) for 3 days. Spirometric variable and percentage of change to baseline forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) after treatment were calculated. Baseline characteristic were comparable in the oral prednisone group (n=44) and in the intramuscular triamcinolone LA groups (n=44). After 7 days of treatment, the mean (SD) FEV1 and FVC in both groups improved statistically over baseline values (P<0.001). The median percentage change improvement of FEV1 between two treatment groups was statistically significant: 68+/-45.3% vs. 53.4+/-46.5%, P=0.04) respectively, but for FVC although improvement with prednisone was better than intramuscular triamcinolone LA groups, it was not statistically significant (52.6+/-40.1% vs. 45.8+/-39.9%, P=0.43) respectively. We conclude that in adults with acute asthma, oral prednisone is more effective than intramuscular triamcinolone LA in improvement of FEV1, but although efficacy of oral prednisone in improvement of FVC is more than intramuscular triamcinolone LA group, this effect is not significant.     

Can airway obstruction be estimated by lung auscultation in an emergency room setting?

OBJECTIVE: Lung auscultation is a central part of the physical examination at hospital admission. In this study, the physicians' estimation of airway obstruction by auscultation was determined and compared with the degree of airway obstruction as measured by FEV(1)/FVC values. METHODS: Two hundred and thirty-three patients consecutively admitted to the medical emergency room with chest problems were included. After taking their history, patients were auscultated by an Internal Medicine registrar. The degree of airway obstruction had to be estimated (0=no, 1=mild, 2=moderate and 3=severe obstructed) and then spirometry was performed. Airway obstruction was defined as a ratio of FEV(1)/FVC <70%. The degree of airway obstruction was defined on FEV(1)/FVC as mild (FEV(1)/FVC <70% and >50%), moderate (FEV(1)/FVC <50% >30%) and severe (FEV(1)/FVC <30%). RESULTS: One hundred and thirty-five patients (57.9%) had no sign of airway obstruction (FEV(1)/FVC >70%). Spirometry showed a mild obstruction in 51 patients (21.9%), a moderate obstruction in 27 patients (11.6%) and a severe obstruction in 20 patients (8.6%). There was a weak but significant correlation between FEV(1)/FVC and the auscultation-based estimation of airway obstruction in Internal Medicine Registrars (Spearman's rho=0.328; P<0.001). The sensitivity to detect airway obstruction by lung auscultation was 72.6% and the specificity only 46.3%. Thus, the negative predictive value was 68% and the positive predictive value 51%. In 27 patients (9.7%), airway obstruction was missed by lung auscultation. In these 27 cases, the severity of airway obstruction was mild in 20 patients, moderate in 5 patients and severe in 2 patients. In 82 patients (29.4%) with no sign of airway obstruction (FEV(1)/FVC >70%), airway obstruction was wrongly estimated as mild in 42 patients, as moderate in 34 patients and as severe in 6 patients, respectively. By performing multiple logistic regression, normal lung auscultation was a significant and independent predictor for not having an airway obstruction (OR 2.48 (1.43-4.28); P=0.001). CONCLUSION: Under emergency room conditions, physicians can quite accurately exclude airway obstruction by auscultation. Normal lung auscultation is an independent predictor for not having an airway obstruction. However, airway obstruction is often overestimated by auscultation; thus, spirometry should be performed.     

Timing and driving components of the breathing strategy in children with cystic fibrosis during exercise

The aim of this study was twofold: first, to determine the breathing strategies of children with cystic fibrosis (CF) during exercise, and secondly, to see if there was a correlation with lung function parameters. We determined the tension-time index of the inspiratory muscles (T(T0.1)) during exercise in nine children with CF, who were compared with nine healthy children with a similar age distribution. T(T0.1) was determined as followed T(T0.1) = P0.1/PImax . T(I)/T(TOT), where P0.1 is mouth occlusion pressure, PImax is maximal inspiratory pressure, and T(I)/T(TOT) is the duty cycle. CF children showed a significant decrease of their forced expiratory volume in 1 sec (FEV1), forced vital capacity (FCV), and FEV1/FVC, whereas the residual volume to total lung capacity ratio (RV/TLC) ratio and functional residual capacity (FRC) were significantly increased (P < 0.001). Children with CF showed mild malnutrition assessed by actual weight expressed by percentage of ideal weight for height, age, and gender (weight/height ratio; 82.3 +/- 3.6%). Children with CF showed a significant reduction in their PImax (69.3 +/- 4.2 vs. 93.8 +/- 7 cmH2O). We found a negative linear correlation between PImax and weight/height only in children with CF (r = 0.9, P < 0.001). During exercise, P(0.1), P0.1/PImax, and T(T0.1) were significantly higher, for a same percent maximal oxygen uptake in children with CF. On the contrary, T(I)/T(TOT) ratio was significantly lower in children with CF compared with healthy children. At maximal exercise, children with CF showed a T(T0.1) = 0.16 vs. 0.14 in healthy children (P < 0.001). We observed at maximal exercise that P0.1/PImax increased as FEV1/FVC decreased (r = -0.90, P < 0.001), and increased as RV/TLC increased (r = 0.92, P < 0.001) only in children with CF. Inversely, T(I)/T(TOT) decreased as FEV1/FVC decreased (r = 0.89, P < 0.001), and T(I)/T(TOT) decreased as RV/TLC increased (r = -0.94, P < 0.001). These results suggest that children with CF adopted a breathing strategy during exercise in limiting the increase of the duty cycle. Two determinants of this strategy were degrees of airway obstruction and hyperinflation.     

Chronic obstructive pulmonary disease is missed in asthmatics in specialty care in Trinidad, West Indies.

SETTING: Underdiagnosis of chronic obstructive pulmonary disease (COPD) in asthmatics attending specialty care in Trinidad, West Indies. OBJECTIVE: To determine the prevalence of COPD in diagnosed asthmatics receiving specialty respiratory care. DESIGN: In a cross-sectional study, 258 asthmatics were screened for lung function measures to examine forced expiratory volume after 1 second (FEV1), forced vital capacity (FVC) and post-bronchodilator FEV1/FVC (COPD was defined as FEV1/FVC < 70%). RESULTS: Of 165 patients evaluated (response rate 64.0%), 53 (32.1%, 95%CI 25.0-39.2) had a study diagnosis of COPD and a mean FEV1/FVC of 60.12 +/- 1.2. Proportionally, more males had COPD (50.9%) than asthma (24.1%, P < 0.001). Patients with COPD were 10 years older than asthmatics (P < 0.001). Persons with asthma who smoked were more likely to have COPD (56.0%) (OR 3.26, 95%CI 1.36-7.80, P = 0.006). In both sexes, FEV1/FVC was lower among older people (P < 0.001), with a greater effect (OR 2.75, 95%CI 1.00-7.56, P < 0.01) seen among men in this cross-sectional study. CONCLUSIONS: One third of diagnosed asthmatics in specialty care also have COPD. Lung function was lower among older persons. Early spirometric evaluation of elderly asthmatics who smoke can determine the presence of COPD and facilitate appropriate management.     

哮喘-慢性阻塞性肺疾病重叠综合征患者呼出气冷凝集液中TNF-α、IL-8、IL-10的检测水平及意义

目的检测哮喘-慢性阻塞性肺疾病重叠综合征(ACOS)患者呼出气冷凝集液(EBC)中肿瘤坏死因子α(TNF-α)、白细胞介素8(IL-8)、IL-10水平,并分析其与该疾病的关系.方法选取2016年2月至2019年3月成都市第三人民医院收治的ACOS患者105例,单纯哮喘患者109例(哮喘组),单纯COPD患者104例(COPD组),另选取同期体检的正常人100例(健康对照组).酶联免疫吸附法检测EBC中TNF-α、IL-8、IL-10水平,自动血液仪检测外周血嗜酸粒细胞比例,利用肺功能仪检测所有受试者第1秒用力呼气容积(FEV1)、用力肺活量(FVC).结果ACOS组、哮喘组、COPD组患者血清IgE水平、外周血嗜酸粒细胞显著高于健康对照组(t=13.594、23.188、3.595;20.886、26.966、20.036,P值均<0.05).ACOS组EBC中TNF-α、IL-8水平显著高于COPD组、哮喘组、健康对照组(t=11.999、13.157、26.807;6.961、7.741、32.496,P值均<0.05),IL-10水平、FEV1%pred显著低于哮喘组、COPD组、健康对照组(t=7.566、9.568、40.129;t=11.539、14.339、28.837,P值均<0.05),FEV1/FVC值显著低于健康对照组(t=16.756,P<0.05);COPD组、哮喘组EBC中TNF-α水平、IL-8水平显著高于健康对照组(t=14.892、14.057;25.544、25.146,P值均<0.05),IL-10水平、FEV1%pred、FEV1/FVC值显著低于健康对照组(t=32.562、31.045;t=17.372、14.939;13.752、16.341,P值均<0.05);哮喘组和COPD组TNF-α、IL-8、IL-10水平、FEV1%pred、FEV1/FVC值比较差异无统计学意义(t=1.015、0.697、1.909、2.658、2.457,P值均>0.05).Pearson检验结果显示,ACOS患者EBC中TNF-α、IL-8水平与FEV1%pred、FEV1/FVC呈负相关(r=-0.463、-0.504;-0.447、-0.476,P值均<0.05);IL-10水平与FEV1%pred、FEV1/FVC呈正相关(r=0.429、0.474,P值均<0.05);Logistic回归分析结果显示,血清IgE水平升高、EBC中TNF-α、IL-8水平升高是ACOS的危险因素(P<0.05),EBC中IL-10水平升高是ACOS的保护因素(P<0.05).结论EBC中TNF-α、IL-8、IL-10水平可能具有潜在的鉴别ACOS生物标志价值.     

慢性阻塞性肺疾病评估测试评分对预后的评估意义

目的探讨慢性阻塞性肺疾病评估测试(CAT)评分与慢性阻塞性肺疾病(COPD)患者预后因素之间的相关性,明确CAT评分对COPD患者预后评估的应用价值。方法选取2013年1月至2015年1月我院呼吸内科住院及门诊就诊的106例COPD患者为研究对象。对106例患者治疗前后进行CAT评分、6 min步行实验(6MWD)、改良英国MRC呼吸困难指数(m MRC)、BODE(B为体质量指数,O为气道阻塞程度,D为呼吸困难分数,E为运动耐力)指数、圣乔治呼吸问卷(SGRQ)评分及肺功能的测定。采用单因素线性相关分析CAT评分与患者各临床特征之间的相关性。结果随着CAT评分的升高,患者6MWD、用力呼气容积(FVC)实测值、FVC实测/预测值、一秒用力呼气容积(FEV1)实测值、FEV1实测/预测值、FEV1/FVC、呼气峰流速(PEF)实测值、PEF实测/预测值均明显降低(P0.05),而m MRC评分、BODE指数及SGRQ总评分明显升高(P0.05);患者经短期治疗后,CAT评分、BODE指数及SGRQ总评分均显著低于治疗前(P0.05),而6MWD、FEV1实测值、FEV1实测/预测值、FEV1/FVC则均显著高于治疗前(P0.05);单因素相关分析发现,治疗前CAT评分与m MRC评分(r=0.254,P=0.018)、BODE指数(r=0.426,P=0.009)及SGRQ总评分(r=0.563,P=0.007)呈显著正相关,与6MWD(r=-0.387,P=0.008)、FVC实测值(r=-0.181,P=0.023)、FVC实测/预测值(r=-0.192,P=0.021)、FEV1实测值(r=-0.201,P=0.016)、FEV1实测/预测值(r=-0.214,P=0.013)及FEV1/FVC(r=-0.223,P=0.012)呈显著负相关;治疗后CAT评分与m MRC评分(r=0.304,P=0.011)、BODE指数(r=0.382,P=0.010)及SGRQ总评分(r=0.621,P=0.004)呈显著正相关,与6MWD(r=-0.407,P=0.007)、FEV1实测值(r=-0.211,P=0.014)、FEV1实测/预测值(r=-0.228,P=0.012)及FEV1/FVC(r=-0.231,P=0.011)呈显著负相关。结论 CAT评分与COPD患者m MRC评分、BODE指数、SGRQ总评分、6MWD及肺功能指标均有较好的相关性,具有较好的预测COPD患者预后的应用价值。     

老年COPD合并呼衰患者血清CysC、VEGF、ACTA水平与病情严重程度的相关性

目的分析老年慢性阻塞性肺疾病(chronic obstructive pulmonary diseases, COPD)合并呼吸衰竭(respiratory failure, RF)患者血清胱氨酸蛋白酶抑制剂C(cystatin protease inhibitor C, CysC)、血管内皮生长因子(vascular endothelial growth factor, VEGF)、激活素A(activin A, ACTA)水平与病情严重程度的相关性。 方法选择四川大学华西医院住院治疗的106例老年COPD合并RF患者为RF组,按动脉血氧分压(PaO₂)将患者分为轻度组36例、中度组41例和重度组29例,另选取医院相同时间段收治的47例单纯COPD患者为非RF组,比较各组患者血清CysC、VEGF、ACTA水平及一秒钟用力呼气容积占预计值百分比(FEV₁)、一秒钟用力呼气容积占用力肺活量百分比(FEV₁/FVC)差异,并分析血清CysC、VEGF、ACTA水平与FEV1%、FEV₁/FVC相关性。 结果RF组患者血清CysC、ACTA水平高于非RF组(P<0.05),VEGF水平、FEV1%、FEV₁/FVC低于非RF组(P<0.05);老年COPD合并RF患者病情越严重,血清CysC、ACTA水平越高,VEGF水平、FEV1%、FEV₁/FVC越低,轻度组、中度组和重度组患者组间存在显著差异(P<0.05);Pearson相关检验结果显示,老年COPD合并RF患者血清CysC与FEV1%、FEV₁/FVC均呈负相关(r＝-0.530,P<0.01;r＝-0.594,P<0.01);VEGF与FEV1%、FEV₁/FVC均呈正相关(r＝0.571,P<0.01;r＝0.668,P<0.01);ACTA与FEV1%、FEV₁/FVC均呈负相关(r＝-0.604,P<0.01;r＝-0.557,P<0.01)。 结论老年COPD合并RF患者血清CysC、VEGF、ACTA水平与其病情严重程度存在密切相关性,有助于对患者及时作出病情评估。     

Effects of ambient ozone on lung function in children over a two-summer period.

There is a general consensus that short term exposure to ozone (O3) causes a decrease in lung function parameters such as forced vital capacity (FVC) and forced expiratory volume in one second (FEV1). The objective of this study was to assess the reproducibility of lung function decrements after ambient O3 exposure over a two-summer period. The authors studied 797 children with a mean age of 8.2 yrs (95% confidence interval: 6.9-9.5) from the second and third grades of ten elementary schools in Austria and southwestern Germany. At the outset the various study locations were stratified into three groups with low (L), medium (M) and high (H) O3 exposure (range of mean O3 concentration in the locations April-October 1994: 24-30 (L); 33-38 (M); 44-52 (H) parts per billion (ppb)). Four lung function tests were performed on each child between March 1994 and November 1995. The increases in FVC and FEV1 recorded from one test period to the next were expressed as mL x day(-1). A significantly lower FVC and FEV1 increase was observed in children exposed to high ambient O3 concentration during the summer season. (FVC in summer 1994: 0.83 (L); 0.56 (M); 0.55 (H) mL x day(-1); p=0.004; and summer 1995: 0.80 (L); 0.63 (M); 0.56 (H) mL x day(-1); p=0.011; FEV1 in summer 1994: 0.48 (L); 0.34 (M); 0.18 (H) mL x day(-1); p=0.004 and summer 1995: 0.68 (L); 0.45 (M); 0.41 (H) mL x day(-1), p=0.006). There was no significant difference in FVC or FEV1 increase between the groups during the winter period. Adjusting for sex, age, height and passive smoke exposure, linear regression revealed a statistically significant negative association of average ambient O3 concentration with the FVC and FEV1 increase in both summers. During the winter period no association of O3 with FVC or FEV1 was observed. In conclusion, in two consecutive summer periods the authors found reproducible lung function decrements in children exposed to high levels of ambient ozone. Reoccurrence of ozone associated lung function deficits might increase the likelihood of persisting effects on the childrens' airways.