Primary biliary cirrhosis: lung involvement

Abstract: Sub-clinical lung impairment, mostly represented by a reduced diffusion of alveolar gases, is a recognised complication of advanced primary biliary cirrhosis. The aim of the study was to evaluate the prevalence and type of pulmonary involvement in primary biliary cirrhosis and the relationship between lung function abnormalities and selected epidemiological and clinical variables. Sixty-one patients with different stages of primary biliary cirrhosis consecutively seen in our outpatient clinic were evaluated. The advancement of primary biliary cirrhosis was characterised by the histological stage, the presence of signs of portal hypertension and the Mayo Risk Score: a Cox regression model using serum bilirubin and albumin levels, prothrombin time, age and degree of oedema as selected variables. We measured static and dynamic lung volumes, by means of a spirometer, and diffusing capacity for carbon monoxide. Rheumatological disorders were evaluated by an independent rheumatologist. No patient complained of respiratory symptoms. Airway obstruction was present in one patient. In 24 patients (39%) the alveolar diffusion capacity was reduced. We did not find any significant relationship between diffusing capacity and smoking habits, advancement of liver disease and concomitant Sjogren syndrome. Reduced diffusion capacity showed a significant correlation with the presence of complete or incomplete CREST syndrome (p<0.01) and with the presence of circulating anti-centromere antibodies (p<0.05). Alveolar diffusion capacity is frequently impaired in patients with primary biliary cirrhosis, usually in the absence of clinical manifestations. These alterations mostly affect patients with concomitant CREST syndrome. Prospective studies are needed to evaluate if these abnormalities will eventually lead to clinical symptoms and if their progression could be influenced by different therapeutic regimens for primary biliary cirrhosis.     

Pulmonary function in patients with diabetes mellitus

BACKGROUND: Pulmonary complications of diabetes mellitus have been poorly characterized. Although some authors have reported normal pulmonary function, others found abnormalities in lung volumes, pulmonary mechanics, and diffusing capacity. SUBJECTS AND METHODS: We studied pulmonary function in a group of patients with diabetes using a combined cardiopulmonary exercise test. Twenty-seven patients with diabetes aged 48 +/- 13 years participated in the study. RESULTS: Overall, forced vital capacity, forced expiratory volume in 1 second, and forced expiratory flow, midexpiratory phase, were within the predicted values, but the residual volume/total lung capacity ratio was slightly elevated. Comparison by diabetes type showed nonsignificant differences in forced expiratory volume in 1 second and forced expiratory flow, midexpiratory phase. Residual volume/total lung capacity ratio was significantly elevated in type 1 patients compared with type 2. Carbon monoxide diffusion capacity (DLCO) was normal in both groups. There was no correlation between the results on pulmonary function test and duration of disease, presence of microangiopathy, or glycemic control. The DLCO was significantly lower in patients with microangiopathic changes, but not when DLCO was corrected for alveolar volume. On the cardiopulmonary exercise test, maximal workload, maximum oxygen uptake, and maximal heart rate were less than predicted, whereas anaerobic threshold and ventilatory reserve were normal. No significant differences were noted in diabetes type, and there was no correlation between parameters of cardiopulmonary exercise test and the other variables. CONCLUSION: Spirometric values are preserved in patients with diabetes mellitus, and there are no defects in diffusing capacity. Cardiovascular factors may account for impaired physical performance. There is no need for routine screening of pulmonary function among diabetic patients.     

The effect of thoracentesis on lung function and transthoracic electrical bioimpedance.

This study aimed to determine the relationship between improvement in lung function and changes in transthoracic electrical bioimpedance (TEB) after thoracentesis in patients with pleural effusions. Fifteen patients with pleural effusions due to either malignant (n = 8) or cardiac (n = 7) diseases were included. Pulmonary function was assessed before and after thoracentesis. During thoracentesis the patients were monitored with TEB. Using linear correlation analysis, the increases for each litre of aspirated thoracic fluid were: forced expiratory volume in 1 s (FEV1) 0.261; forced vital capacity (FVC) 0.331; total lung capacity (TLC) 0.58; and the lung diffusing capacity (DLCO); 2.4 ml min-1 mmHg-1. Baseline impedance increased by 2.3 Ohm l-1 aspirated thoracic fluid. The relative increase in baseline impedance was twice as high for patients with cancer as for patients with heart failure (P < 0.05). We found only minor changes in systolic blood pressure and mean arterial pressure. The improvements in diffusing capacity, airflow, and lung volumes after thoracentesis are correlated to an increase in baseline impedance, but changes are dependent on the primary disease.     

Correlation of pulmonary function variables with hemodynamic measurements in patients with pulmonary arterial hypertension

Introduction: A reduced diffusing capacity of the lung for carbon monoxide (DLCO) measured during a pulmonary function test can suggest pulmonary arterial hypertension (PAH). The DLCO has been reported to weakly correlate with pulmonary hemodynamics. Objective: To determine whether the relationship between the DLCO and pulmonary arterial pressures can be strengthened by normalizing the DLCO to spirometric variables. Patient and Methods: Patients were seen at a tertiary care referral center. Consecutive subjects who underwent right heart catheterization (RHC) for the evaluation of suspected PAH from 01 January 1991 through 01 October 2006 were identified. Pulmonary function testing (PFT) data performed within 60 days of the RHC was collected. Spearman rank correlation between PFT and RHC variables was calculated. Results: One hundred thirty‐eight patients who had an RHC performed had complete PFTs available. No significant correlation was identified between the mean pulmonary artery pressure and the pulmonary vascular resistance against the DLCO, nor the DLCO when normalized to: forced expiratory volume in 1 s, forced vital capacity, total lung capacity or alveolar volume. Spirometric subgroups were identified by standard definitions of restrictive and/or obstructive ventilatory defects. Clinical subgroups were classified based on the clinically diagnosed cause of the patient's PAH. Again, no significant correlation was identified between the PFT variables and RHC measurements in these stratified subgroups. Conclusion: In patients with suspected PAH, invasive hemodynamic measurements of PAH do not correlate with PFT variables, even when corrected for spirometric volumes, and regardless of the subgroup of ventilatory physiology or clinical diagnosis. Please cite this paper as: Arunthari V, Burger CD and Lee AS. Correlation of pulmonary function variables with hemodynamic measurements in patients with pulmonary arterial hypertension. Clin Respir J 2011; 5: 35–43.     

Pulmonary function before and sequentially after valve replacement surgery with correlation to preoperative hemodynamic data

Hemodynamic results after valve replacement surgery are well documented, but there are few follow-up studies on pulmonary function. Pulmonary function and hemodynamic studies were made, preoperatively, in 149 patients with predominant, mitral, aortic or combined mitral and aortic stenosis. A sequential postoperative follow-up of the pulmonary function was performed on 88 patients for as long as 125 wk after valve replacement. All patients had reduced preoperative values for forced vital capacity (FVC), single-breath carbon monoxide diffusing capacity (DLCO), forced expiratory volume in one second, peak expiratory flow rate, and maximal flow after exhalation of 75, 50, and 25% of FVC, and increased total airway resistance, resistance during expiration, and residual volume. The aortic group tended toward more normal values. There was significant correlation between the pulmonary function parameters and the hemodynamic data. In the early postoperative period (10 wk), deterioration of pulmonary function was significant in the aortic group and variable in the mitral and the combined groups; these responses correlated with preoperative hemodynamic and pulmonary function status. Between 10 to 125 wk, all patients showed progressive improvement, especially among those in the mitral group. Patients who died during or soon after mitral valve replacement were found to have significantly lower FVC and DLCO and significantly higher peripheral vascular resistance and cardiothoracic ratio. It is concluded that deterioration in pulmonary function is correlated to severity of cardiac dysfunction, and is reversible late after surgery, except in very advanced cases that have poor prognosis.     

Pulmonary function tests cannot predict exercise-induced hypoxemia in chronic obstructive pulmonary disease

We studied 40 patients with chronic obstructive pulmonary disease (COPD) to determine whether measurements of pulmonary function could predict a fall in arterial oxygen pressure (PaO2) with exercise. The PaO2 fell more than 3 mm Hg in 21 patients (group 1), did not change (+/- 3 mm Hg) in nine patients (group 2), and increased more than 3 mm Hg in ten patients (group 3). Group 3 had significantly less severe expiratory obstruction than groups 1 and 2. The most significant variables in predicting a change in PaO2 with exercise were the ratio of the forced expiratory volume in one second over the forced vital capacity (FEV1/FVC) and the single-breath carbon monoxide diffusing capacity (Dsb). Measurements of FEV1/FVC of 0.50 or more and Dsb of 20 ml/min/mm Hg or more were 100 percent predictive in excluding a fall in PaO2 with exercise. Measurements below these thresholds could not be used reliably to predict which patients would develop worsening hypoxemia with exercise. Because of wide variability in reference values from eight different published studies for diffusing capacity, recommended criteria based on the percent predicted Dsb should be used with caution. We conclude that pulmonary function measurements cannot be used to predict exercise-induced hypoxemia in patients with COPD; however, the measurements may be useful in identifying patients whose condition is less severe who are unlikely to develop worsening hypoxemia with exercise.     

A follow-up study of pulmonary function in patients with primary Sjögren's syndrome

Summary Twenty-seven patients (25 women, 2 men) with primary Sjögren's syndrome, previously reported to have reduced pulmonary diffusing capacities were reexamined in a 7-year follow-up in order to evaluate longitudinal alterations in pulmonary function. Primary Sjögren's syndrome was diagnosed according to the Copenhagen criteria. The present examination revealed normal and unchanged values for vital capacity, forced expiratory volume in 1 s, maximal expiratory flow at 50% of expired vital capacity (MEF50), and diffusing capacity per liter alveolar volume. Total diffusing capacity (P<0.01) and MEF75 (P<0.05), were, however, significantly reduced compared with the predicted values, indicating pulmonary involvement primarily affecting the small airways. The longitudinal examination, furthermore, showed increasing values for total diffusing capacity (P<0.02), diffusing capacity per liter alveolar volume (P<0.001), and MEF75 (P<0.02), suggesting an improvement in lung status in the course of time. No correlation was found between MEF75 and diffusing capacities, nor between alterations in pulmonary function and complaints of dyspnoea, tiredness, cough, expectoration, tobacco smoking, or medical treatment with bromhexine, glucocorticosteroids, essential fatty acids, or nonsteroid antiinflammatory drugs.     

Longitudinal follow-up study of 11 patients with pulmonary lymphangioleiomyomatosis: diverse clinical courses of LAM allow some patients to be treated without anti-hormone therapy

OBJECTIVE: The purpose of this study is to clarify the existing issues on the clinical diversity, natural history, and mode of disease progression of pulmonary lymphangioleiomyomatosis (LAM). METHODOLOGY: Eleven patients with LAM were reviewed retrospectively with special reference to serial changes in pulmonary function and radiological findings during the course of their disease, treatment, and outcome. All patients were female with a mean age of 33.8 years at presentation and the observation period ranged from 2.1 to 20.8 years (mean 7.4 years). RESULTS: Four of six patients, treated with anti-hormone therapy, presented with exertional dyspnoea, marked airflow limitation (forced expiratory volume in 1 s/forced vital capacity, 23-38%), and severely impaired diffusing capacity (%DLCO, 21.4-36% of the predicted). The remaining two patients showed only a decreased diffusing capacity (70.6% and 59.4% of the predicted) which rapidly deteriorated with subsequent development of airflow limitation. Repeated chest computed tomographic (CT) examinations revealed increasing numbers of cysts with simultaneous loss of normal lung parenchyma in these two patients. In contrast, the five patients who received no anti-hormone therapy had no respiratory symptoms aside from pneumothorax at onset. Remarkable differences were noted, with pulmonary function being well maintained and slow progression of cystic changes on CT being observed in the latter group. CONCLUSIONS: Diverse clinical courses observed in patients with pulmonary LAM can be well delineated and assessed by periodic examinations including pulmonary function tests and chest CT imaging. Anti-hormone therapy is not always necessary for a certain group of LAM patients and they appear to have a stable course and favourable outcomes without anti-hormone treatment.     

Nitrogen washout and mortality

We studied the association between different tests of pulmonary function and subsequent mortality. Subjects were drawn from an epidemiology study of chronic obstructive pulmonary disease. Between 1971 and 1976, 2,539 nonpatient adults had tests of forced expiration, diffusing capacity, and single-breath nitrogen washout. By 1981, 115 of those subjects had died, including 3 from known lung disease. In assessing the relationship between lung function and mortality, the following tests of pulmonary function were examined: forced expiratory volume in one second as a percentage of forced vital capacity, forced expiratory volume divided by height cubed, slope of phase III from the single-breath nitrogen test, closing capacity, diffusing capacity for CO, and the ratio of maximal flow at 75% to that at 25% vital capacity. When adjustments for age and smoking were made, slope of phase III was strongly associated with mortality, even more so than tests of forced expiration. There are two possible explanations for this striking relationship between these observed abnormalities of lung function and subsequent overall mortality (which is largely from nonpulmonary disease): the lungs may serve to protect other systems of the body and therefore poor pulmonary function may contribute to a number of diseases leading to death, or lung function may merely reflect existing disorders in other systems of the body, and the observed association between mortality and pulmonary function is a byproduct of nonpulmonary diseases.     

Pulmonary function in singers and wind-instrument players

Previous studies suggest that pulmonary function of singers and wind-instrument players may be better than normal control subjects due to breath-control training; however, prior studies were poorly controlled or limited in scope. In the present study, we compare 34 singers and 48 wind instrumentalists with a control group of 31 string or percussion instrumentalists using a pulmonary questionnaire, measurements of inspiratory and expiratory pressures, and spirometry. We found no significant difference between groups in maximum voluntary ventilation, forced expiratory volume in one second (FEV1), forced vital capacity (FVC), mean forced expiratory flow during the middle half of the FVC, the FEV1/FVC, peak expiratory pressure, or peak inspiratory pressure, independently or when corrected for age, sex, height, weight, years performing, smoking, presence or absence of cough, or sputum production. Smoking correlated negatively with measurements of pulmonary function in all groups. There was evidence of a heightened awareness of health among singers, who exercised more and smoked less than their colleagues. The differences in health habits may account in part for the myth of improved pulmonary volumes among singers.     

Assessment of emphysema in COPD: a functional and radiologic study

OBJECTIVES: A combination of functional measurements reflecting a decrease in maximum flow, a degree of lung hyperinflation, the relationship between maximum inspiratory and expiratory flows, bronchodilator response, and diffusing capacity of the lung for carbon monoxide (DLCO) was used to quantify the extent of emphysema, as assessed by high-resolution CT (HRCT) scanning. DESIGN: Forced inspiratory and expiratory spirometry, lung volumes, reversibility test, and single-breath diffusing capacity were assessed before and after inhaling albuterol, 200 microg. Relationships between lung function variables and emphysema extent, as determined by HRCT scanning, were tested by univariate and multivariate analyses. SUBJECTS: Thirty-nine COPD outpatients with moderate-to-severe obstruction. MEASUREMENTS AND RESULTS: Emphysema extent, as assessed by HRCT scanning, ranged from 18 to 70%. All of the lung function parameters that were studied, except for the change in FEV1 percent predicted after salbutamol inhalation, correlated significantly with the extent of emphysema (r2 range, 0.19 to 0.44). Functional residual capacity, forced expiratory flow at 50% of FVC/forced inspiratory flow at 50% of FVC, DLCO/alveolar volume ratio, and bronchodilator-induced change in FEV1/FVC ratio were the only variables retained by stepwise multiple regression analysis. The multiple regression model explained 71% of the variability of emphysema extent measured by HRCT scanning. CONCLUSIONS: The combination of lung function measurements reflecting lung hyperinflation, bronchial collapsibility, lung diffusing capacity, and bronchodilator response provides a good estimate of the extent of emphysema, as evaluated by HRCT scanning. These data suggest that pulmonary function tests are useful in assessing and monitoring parenchymal damage in COPD patients.     

河北省SARS患者出院20个月后肺功能调查分析

目的 分析严重急性呼吸综合征（SARS）患者出院后肺功能变化，了解SARS患者预后。方法 调查了203例SARS患者康复20个月后健康状况，对遗留干咳、活动性气短者行肺功能检查，合并骨关节症状者进行相应部位磁共振（MRI）检查；同时回顾其住院期间的临床资料。结果 33例出院者遗留干咳、活动性气短等症状，其中32例同时合并有骨关节症状，住院期间均接受了抗感染、抗病毒及适量。肾上腺糖皮质激素治疗。肺功能检测发现部分出院者FEV1％、FEV1／FVC％、V50％预计值和D1CO％预计值降低，表现为轻度肺功能异常。合并骨坏死者FEV。／FVC显著低于未合并骨坏死者，而发病年龄和高热天数显著增高（P〈0．05）；两者弥散功能指标（DLCO％）差异无统计学意义。结论 SARS患者出院20个月后仍有部分患者存在轻度肺功能异常，以弥散障碍为主，少数存在小气道功能障碍和肺通气障碍；病情较重者易合并骨坏死，而肺弥散功能障碍恢复较好。     

Pulmonary function in alcoholics

Twenty-three chronic alcoholics were investigated by means of pulmonary function studies. All 23 patients had respiratory symptoms. Clinically, 21 (91 per cent) of 23 patients were diagnosed as having chronic bronchitis, and 14 patients (60 per cent) had dyspnea. The maximal mid-expiratory flow and single breath diffusing capacity for carbon monoxide (SBDCO) were abnormal in 16 (70 per cent) and 14 (61 per cent) patients, respectively. Twenty-two of 23 patients had one or more abnormal function. The total lung capacity, residual volume, vital capacity, 1 second forced expiratory volume and SBDCO progressively declined with increasing alcohol consumption. An attempt was made to separate the pulmonary effects of alcohol from (1) the effects of previous pulmonary infections, (2) the effects of cigarette smoking, and (3) the effects of cirrhosis of the liver. The data suggest that either alcohol itself through some unknown mechanism may be a causative agent in producing lung disease or that alcohol makes a higher percentage of the population susceptible to the harmful effects of cigarette smoking.     

Pulmonary dysfunction in advanced liver disease: Frequent occurrence of an abnormal diffusing capacity

PURPOSE: Abnormalities in pulmonary function have been reported in association with chronic liver disease of varied etiology. The aim of this study was to better define the frequency and nature of these abnormalities in patients who were being evaluated for liver transplantation. PATIENTS AND METHODS: We performed a battery of pulmonary function tests and chest radiographs in 116 consecutive patients (50 men, 66 women; aged 19 to 70 years, mean 44.6 years) with severe advanced liver disease who were hospitalized specifically for evaluation for possible orthotopic liver transplantation and were able to perform technically satisfactory tests. In 17 patients, quantitative whole-body technetium-99m macroaggregated albumin perfusion scanning was also performed for assessment of possible right-to-left shunting through intrapulmonary vascular dilatations. RESULTS: The most commonly affected test of lung function was the single-breath diffusing capacity for carbon monoxide (DLCO), which was abnormal in 48%, 45%, and 71% of patients who never smoked, former smokers, and current smokers, respectively. Ventilatory restriction was noted in 25% of all patients, airflow obstruction (reduced ratio of forced expiratory volume in 1 second to forced vital expiratory volume in 1 second to forced vital capacity) in only 3%, and a widened alveolar-arterial oxygen gradient in 45%. Diffusion impairment was accompanied by a restrictive defect in only 35% of the patients and by an abnormally widened alveolar-arterial oxygen gradient in 60%. When diffusion impairment was accompanied by an oxygenation defect, it was also associated with a significantly increased right-to-left shunt fraction (mean 24.9%) assessed from quantitative whole-body perfusion imaging. On the other hand, isolated diffusion impairment unaccompanied by significant hypoxemia (noted in approximately a third of the patients with a reduced DLCO) was not associated with evidence of significant intrapulmonary shunting (mean right-to-left shunt fraction 6.7%). CONCLUSIONS: Most patients with advanced liver disease have one or more types of abnormality in lung function, a reduced DLCO being the single most common functional defect. Mechanisms accounting for the abnormality in gas transfer may include intrapulmonary vascular dilatations, diffuse interstitial lung disease, pulmonary vaso-occlusive disease, and/or ventilation-perfusion imbalance.     

Assessment of pulmonary function in COPD

Pulmonary function testing is used in the diagnosis of chronic obstructive pulmonary disease (COPD) and the staging of COPD severity. The current diagnostic criterion for airflow obstruction is a ratio of forced expiratory volume in 1 second (FEV (1)) to forced vital capacity (FVC) < 70%. However this absolute definition can lead to false-negative determinations in younger patients and false-positive determinations in the elderly. Nevertheless, screening spirometry is advocated and becomes feasible in the physician office setting with the availability of compact, relatively affordable apparatus that meets the appropriate technical specifications. Spirometry should be complemented by measurement of lung volumes using body plethysmography in those with evidence of airflow obstruction. Small airways disease can be detected by various techniques that measure airway and total respiratory system resistance. There is renewed interest in the forced oscillation technique and impulse oscillometry because of their noninvasiveness and potential ability to distinguish small from larger airway disease. Finally, pulmonary function testing has an important role in preoperative risk assessment; for example, in patients being considered for lung volume reduction surgery or resection of a lung nodule.     

The effect of Pseudomonas aeruginosa on pulmonary function in patients with bronchiectasis.

Bronchiectasis patients are susceptible to infection with Pseudomonas aeruginosa. Isolation is associated with increased severity of disease, greater airflow obstruction and poorer quality of life. It is not known whether infection by P. aeruginosa is a marker of disease severity or contributes to disease progression. Consecutive non-cystic fibrosis adult bronchiectasis outpatients (n = 163) with multiple sputum cultures and follow-up pulmonary function tests were designated, according to isolation of P. aeruginosa, as "never infected" (group 1; n = 67), "intermittently isolated" (group 2; n = 82) and "chronically infected" (group 3; n = 14). Based upon change in forced expiratory volume in one second (FEV(1)) % predicted levels at >or=2 yrs after presentation, longitudinal behaviour was characterised as "improvement" (>or=10% rise), "decline" (>or=10% fall) or "stability". Baseline pulmonary-function tests and longitudinal behaviour were examined in relation to pseudomonas status. There was no difference between the groups in age, sex, smoking habit or length of follow-up. Baseline FEV(1) levels were highest in group 1 (mean+/-sd: 77.4+/-24.3) and higher in group 2 (67.3+/-25.7) than in group 3 (55.2+/-18.5). The same significant trends were seen for baseline FEV(1)/forced vital capacity ratios and diffusing capacity of the lung for carbon monoxide levels. Subsequent longitudinal behaviour was linked to baseline FEV(1) levels, which were lowest in patients with improvement and lower in association with decline than with stability. However, longitudinal behaviour did not differ between groups 1, 2 and 3, either before or after adjustment for baseline FEV(1) levels. Infection by Pseudomonas aeruginosa occurs in bronchiectasis patients with more severe impairment of pulmonary function but does not influence rate of decline in pulmonary function either before or after adjustment for baseline disease severity. Thus, Pseudomonas aeruginosa is a marker of bronchiectasis severity but is not linked to an accelerated decline in pulmonary function.     

Values of high-resolution computed tomography and pulmonary function tests in managements of patients with chronic hepatitis C virus infection

AIM: To investigate pulmonary involvement via pulmonary function tests (PFT) and high-resolution computed tomography (HRCT) in patients with chronic hepatitis C virus (HCV) infection. METHODS: Thirty-four patients with chronic HCV infection without diagnosis of any pulmonary diseases and 10 healthy cases were enrolled in the study. PFT and HRCT were performed in all cases. RESULTS: A decrease lower than 80% of the predicted value was detected in vital capacity in 9/34 patients, in forced expiratory volume in one second in 8/34 patients, and in forced expiratory flow 25-75 in 15/34 patients, respectively. Carbon monoxide diffusing capacity (DLCO) was decreased in 26/34 patients. Findings of interstitial pulmonary involvement were detected in the HRCT of 16/34 patients. Significant difference was found between controls and patients with HCV infection in findings of HRCT (chi2=4.7, P=0.003). Knodell histological activity index (KHAI) of 28/34 patients in whom liver biopsy was applied was 9.0+/-4.7. HRCT findings, PFT values and DLCO were not affected by KHAI in patients with HCV infection. In these patients, all the parameters were related with age. CONCLUSION: We suggest that chronic hepatitis C virus infection may cause pulmonary interstitial involvement without evident respiratory symptoms.     

HLA-DQw alloantigens and pulmonary dysfunction in rheumatoid arthritis

HLA-DR4 and keratoconjunctivitis sicca (secondary Sj?gren's syndrome) are associated with abnormal pulmonary function in patients with rheumatoid arthritis. Since recent investigations have found that much of the genomic polymorphism of the HLA-DR4 haplotype comes from the closely linked DQw allele, we reanalyzed this set of data to evaluate the relationship between the DQw allotypes and pulmonary function in rheumatoid arthritis. Using a step-wise regression analysis, we found that the presence of DQw1 was a stronger predictor of an abnormal forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and carbon monoxide diffusing capacity (D) than the presence of DR4, keratoconjunctivitis sicca, smoking status, or any other clinical parameter. DQw1-positive patients had a mean (+/- SD) percent of predicted FEV1, FVC, and D of 84.2 (+/- 19.8), 88.0 (+/- 17.9) and 85.6 (+/- 20.9) percent, respectively, all significantly lower than DQw-1 negative patients (p = 0.02, 0.02, and 0.03). Smokers with the heterozygous phenotype, DQw1/DQw3, tended to have obstructive disease of the airways, with a mean (+/- SD) FEV1 of 80.1 +/- 24.4 percent of predicted, compared to 95.7 +/- 12.1 percent of predicted in DQw1/DQw3-negative individuals (p = 0.03). Patients who had a DQw2 allele were more likely to have normal pulmonary function. We conclude that the HLA-DQw1 allotype is a strong predictor of abnormal pulmonary function and that it may identify smoking subjects with rheumatoid arthritis subjects who are prone to develop obstruction of airflow.     

Changes in the forced expiratory spirogram in young male smokers.

Forced expiratory spirograms and peak expiratory flow were measured in 102 resident male medical students (60 nonsmokers and 42 smokers). Forced vital capacity; forced expiratory volume in 1 sec; forced expiratory volume in 1 sec expressed as a percentage of forced vital capacity; forced expiratory flows between 80 and 70 per cent, between 55 and 45 per cent, between 30 and 20 per cent, and between 15 and 5 per cent of the forced vital capacity; forced expiratory time for the last 0.5 liter of the forced vital capacity; and maximal mid-expiratory flow were determined from the forced expiratory spirogram. Peak expiratory flow, all forced expiratory flows (except the forced expiratory volume in 1 sec), and the ratio of forced expiratory volume in 1 sec to forced vital capacity were significantly lower, and forced expiratory time for the last 0.5 liter of the forced vital capacity was significantly higher in the heavy smokers (those who had smoked a lifetime total of more than 10,000 cigarettes) than the nonsmokers. The light smokers (those who smoked a lifetime total of fewer than 10,000 cigarettes) had values between those of nonsmokers and the heavy smokers. Thus, a definite dose-related response to smoking was seen. Flows at lower lung volumes showed greater percentage changes than flows at higher lung volumes. The forced expiratory flow between 30 and 20 per cent of the forced vital capacity was the most sensitive test for detecting abnormality in smokers. Among heavy smokers, 58 per cent had abnormally low forced expiratory flow between 30 and 20 per cent of the forced vital capacity, whereas only 47 per cent had abnormally low ratio of forced expiratory volume in 1 sec to forced vital capacity, and 32 percent had abnormally low maximal mid-expiratory flow. The results show that even subjects with short smoking histories may have changes in pulmonary function that probably reflect narrowing of small airways. Moreover, these changes can easily be detected by simple tests, such as evaluation of a forced expiratory spirogram.     

Pulmonary function 4 months after coronary artery bypass graft surgery

The objective of this study was to describe the pulmonary function and pain 4 months after coronary artery bypass graft surgery. Twenty-five male patients performed pulmonary function tests before surgery, on the 4th postoperative day and 4 months after surgery. A severe reduction in pulmonary function was present after surgery. Four months postoperatively, the patients still showed a significant decrease (6-13% of preoperative values) in vital capacity (P<0.001), inspiratory capacity (P<0.001), forced expiratory volume in 1 s (P<0.001) peak expiratory flow rate (P<0.001), functional residual capacity (P=0.05) total lung capacity (P<0.001) and single-breath carbon monoxide diffusing capacity (P<0.01). Residual volume and single-breath carbon monoxide diffusing capacity per litre of alveolar volume had returned to the preoperative level. Four months postoperatively, the median values for sternotomy pain while taking a deep breath was 0.2 and while coughing 0.3 on a 10 cm visual analogue pain scale. In conclusion, a significant restrictive pulmonary impairment persisting up to 4 months into the postoperative period was found after CABG. Measured levels of pain were low and could not explain the impairment.