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PubMed2002

Accuracy of history, wheezing, and forced expiratory time in the diagnosis of chronic obstructive pulmonary disease.

OBJECTIVE: To determine the accuracy of the history and selected elements of the physical examination in the diagnosis of chronic obstructive pulmonary disease (COPD). DESIGN: Independent blind comparison of the standard clinical examination (evaluating the accuracy of history, wheezing, and forced expiratory time [FET]) with spirometry. The gold standard for diagnosis of COPD was a forced expiratory volume at 1 second (FEV1) below the fifth percentile (adjusted for patient height and age). SETTING: Seven sites in 6 countries, including investigators from primary care and secondary care settings. PARTICIPANTS: One hundred sixty-one consecutive patients with varying severity of disease (known COPD, suspected COPD, or no COPD) participated in the study. MAIN RESULTS: One hundred sixty-one patients (mean age 65 years, 39% female, 41% with known COPD, 27% with suspected COPD, and 32% normal) were recruited. Mean (+/-SD) FEV1 and forced vital capacity were 1,720 (+/-830) mL and 2,520 (+/-970) mL. The likelihood ratios (LR) for the tested elements of the clinical examination (and their P values on chi2 testing) were: self-reported history of COPD, 5.6 (P <.001); FET greater than 9 seconds, 6.7 (P < 0.01); smoked longer than 40 pack years, 3.3 (P =.001); wheezing, 4.0 (P <.001); male gender, 1.6 (P <.001); and age over 65 years, 1.6 (P =.025). The accuracy of these elements was not appreciably different when reference standards other than FEV1 below the 5th percentile were applied. Only 3 elements of the clinical examination were significantly associated with the diagnosis of COPD on multivariate analysis: self-reported history of COPD (adjusted LR 4.4), wheezing (adjusted LR 2.9), and FET greater than 9 seconds (adjusted LR 4.6). Area under the receiver operating characteristic curve for the model incorporating these 3 factors was 0.86. CONCLUSIONS: Less emphasis should be placed on the presence of isolated symptoms or signs in the diagnosis of COPD. While numerous elements of the clinical examination are associated with the diagnosis of COPD, only 3 are significant on multivariate analysis. Patients having all 3 of these findings have an LR of 33 (ruling in COPD); those with none have an LR of 0.18 (ruling out COPD).

Female↗
PubMed1999

The effect of gestational parity on FEV1 in a group of healthy volunteer women.

In the past, studies utilizing within-subject comparisons of small groups of pregnant women showed that forced expiratory volume in 1 s (FEV1) remained essentially unchanged during pregnancy. However, one of the findings from an epidemiological study was that women with greater number of children experienced a faster decline of FEV1. The aim of this study was to examine the effect of parity on FEV1 in a group of healthy volunteer women. To this end, cross-sectional multiple regression analyses of data from 397 healthy women participants in the Baltimore Longitudinal Study of Aging (BLSA) with a mean (range) age of 47.7 (18-92) years were performed. Similar analyses were done using the younger (50 years or less) and the older (> 50 years) subgroups. After controlling for age, height, weight, and smoking, parity as a dichotomous variable was associated with a higher FEV1 in women of child-bearing age (0.139 1; P = 0.02) but not in the older women. There was a modest link with the number of children (P = 0.05), with the first child possibly having the greatest effect on FEV1. We could not account for the effect of parity on FEV1 by the educational level, occupation, health status of the women, or by the presence of a cohort effect. Thus the nulliparous state is associated with lower FEV1 in this group of healthy adult women of child-bearing age.

Adult↗
PubMed1986

Reduction of lung elasticity due to training and expiratory flow limitation during exercise in competitive female rowers.

Lung elasticity and lung volumes at rest were measured in 22 female rowers, in 14 women who just started with rowing, in 21 female cyclists, and in 9 male rowers. The female rowers had a higher specific static and dynamic lung compliance (P less than 0.01) and a lower recoil pressure at functional residual capacity (P less than 0.05) as compared to the other three groups. According to their age, height, and fat-free mass, the female rowers had a normal vital capacity. The residual volume, the functional residual capacity, and the fast expiratory volume in 1 s were also normal. During an increased load test till exhaustion on a bicycle ergometer, the transpulmonary pressure and the expiratory flow were measured. While the expiratory transpulmonary pressure at exhaustion in the female rowers was not markedly lower than in the other groups, expiratory flow did not increase linearly with decreasing expiratory transpulmonary pressure in most of the female rowers. In the other three groups, there was a linear relation between expiratory flow and pressure. The higher lung compliance and lower elastic recoil in the female rowers caused the flow-limiting pressure to be reached at a lower level. The difference in lung elasticity between the male and female rowers showed that the physical stress on the lungs during rowing is not alike in women and men. We assume that the typical female physique requires extra fixation of the trunk during the pull phase of the rowing stroke, which could lead to loss of lung elasticity in female rowers.

Adolescent↗
PubMed1977

Enhancement of exercise-induced asthma by cold air.

To study the possibility that the inhalation of cold air accentuates the bronchoconstrictor response to exercise in asthma, eight subjects exercised while breathing air at ambient or subfreezing temperatures. On a separate day, cold air was breathed at rest so as to isolate the effects of this stimulus. Pulmonary mechanics were measured before and after each experiment. In all subjects acute bronchoconstriction followed the control exercise challenge. With cold-air breathing, however, the magnitude of the response was markedly enhanced. Residual volume increased 158 per cent more than it did previously, and specific conductance and one-second forced expiratory volumes changed an additional 85 and 100 per cent, respectively. The effects of cold air at rest were very small. The results demonstrate a positive interaction of two common naturally occurring stimuli in the induction of asthmatic attacks, and constitute objective verification of a frequent clinical complaint.

Adult↗
PubMed1985

The long-term pulmonary sequelae of prematurity: the role of familial airway hyperreactivity and the respiratory distress syndrome.

Respiratory distress syndrome of the newborn, prematurity, and familial airway hyperreactivity may contribute to long-term pulmonary sequelae. We assessed the role of each by testing pulmonary function and airway reactivity in 11 prematurely born children who survived the respiratory distress syndrome and in 11 prematurely born children who had no neonatal respiratory disease, each of whom was paired with a sibling born at term. The subjects were between 7 and 12 years of age when studied. Airway reactivity was also assessed in their mothers. The group who had had the respiratory distress syndrome had higher ratios of residual volume to total lung capacity and lower values for forced expiratory volume in one second than did their siblings or normal controls (P less than 0.01). Expiratory flow was decreased in both groups born prematurely (P less than 0.02) and was related to neonatal exposure to oxygen (r = -0.71, P less than 0.02). The incidence of airway hyperreactivity was elevated in all groups, including the mothers. These data suggest that long-term pulmonary sequelae of the respiratory distress syndrome of the newborn are related to the disease, its treatment, or both, and to airway hyperreactivity. In prematurely born children without neonatal lung disease, the sequelae are related to airway hyperreactivity. The possibility of a relation between familial airway hyperreactivity and premature birth is suggested.

Airway Obstruction↗
PubMed1991

The influence of a family history of asthma and parental smoking on airway responsiveness in early infancy.

BACKGROUND: Airway responsiveness to inhaled nonspecific bronchoconstrictive agents has been demonstrated in normal, healthy infants. However, it is unknown whether airway responsiveness is present from birth or if it develops as a result of subsequent insults to the respiratory tract. To investigate this question, we assessed airway responsiveness in 63 normal infants at a mean age of 4 1/2 weeks. METHODS: Respiratory function was measured with use of the partial forced expiratory flow-volume technique to determine the maximal flow at functional residual capacity (VmaxFRC). The infants inhaled nebulized histamine at sequentially doubled concentrations (0.125 to 8.0 g per liter), until a concentration was reached at which the VmaxFRC fell by 40 percent from the base-line value (PC40) or until a concentration of 8.0 g per liter was reached. We also assessed maternal serum levels of IgE, cord-serum levels of IgE, the infants' skin reactivity to several allergens, and the parents' responsiveness to histamine and obtained family histories of asthma and smoking. RESULTS: Airway responsiveness was increased in infants with a family history of asthma (n = 19; median PC40, 0.78 g per liter; 95 percent confidence interval, 0.44 to 1.15; P less than 0.01), parental smoking (n = 13; median PC40, 0.52 g per liter; 95 percent confidence interval, 0.43 to 5.40; P less than 0.05), or both (n = 20; median PC40, 0.69 g per liter; 95 percent confidence interval, 0.37 to 2.10; P less than 0.05), as compared with the infants with no family history of asthma or smoking. The infants with no family history of asthma or smoking had a median PC40 of 2.75 g per liter (95 percent confidence interval, 1.48 to 4.00). No significant relations were detected between the immunologic variables and the PC40 in the infants. CONCLUSIONS: This study indicates that airway responsiveness can be present early in life and suggests that a family history of asthma or parental smoking contributes to elevated levels of airway responsiveness at an early age.

Asthma↗
PubMedDate not supplied

Health status of funeral service workers exposed to formaldehyde.

A study of 84 funeral service workers and 38 control subjects in Toronto, Canada, revealed that the embalmers reported chronic bronchitis, dyspnea, and nasal, eye, and skin irritation more frequently than controls. Apprentices reported symptoms and exhibited signs of irritation more frequently than experienced embalmers, but both of these groups were more affected than the inactive embalmers or the controls. Airborne formaldehyde levels were 0.36 +/- 0.19 ppm (mean +/- standard deviation) during 22 embalming procedures. General ventilation was shown to significantly lower the levels. No significant change in forced vital capacity, forced expiratory volume in 1 sec, FEF50 or FEF75 was demonstrated with formaldehyde exposure nor were the baseline lung function results significantly different from those 38 unexposed controls. Based on patch testing, 4% and 10% were sensitive to formaldehyde and glutaraldehyde, respectively, whereas none of the controls exhibited positive reactions.

Adult↗
PubMedDate not supplied

Duration of enhanced responsiveness upon re-exposure to ozone.

It has been repeatedly observed that ozone (O3) re-exposure within 24 h elicits enhanced pulmonary function responses. However, there are only limited observations concerning re-exposure to O3 at intervals between 24 h and several days. The present study was designed to assess the effects of re-exposure to 0.35 ppm O3 at intervals of 24, 48, 72, and 120 h. Forty young adult male subjects were assigned randomly to one of four groups in ascending order of time to re-exposure (groups 1-4). Each exercised on a bicycle ergometer for 60 min at a workload that elicited a mean ventilation of 60 l/min on three occasions: protocol 1 (P1), filtered air (FA); protocol 2 (P2), 0.35 ppm O3; and protocol 3 (P3), 0.35 ppm O3. In addition to standard pulmonary function measures, specific airway resistance (SRaw); exercise ventilatory pattern, i.e., respiratory frequency (fR) and tidal volume (VT); and subjective symptoms (SS) were assessed. Statistical analysis revealed significant differences (p less than .05) for all groups between the FA (P1) responses and those for the two O3 exposures (P2, P3) for forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1.0), SRaw, fR, VT, and SS. When the two O3 exposures (P2 and P3) were compared, only group 1 (24 h) responses were statistically significant upon re-exposure: FEV1.0, -16.1 vs. -30.4% (p less than .003); SRaw, 20.5 vs. 34.5% (p less than .05); fR, 44.2 vs. 65.3% (p less than .001); and SS (p less than .015).(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Physiological↗
PubMedDate not supplied

A longitudinal study of lung function in jute processing workers.

A 5-y follow-up study of pulmonary function was conducted in 1982 and in 1987 for 50 current and retired jute-processing workers who had been employed for more than 10 y in a jute mill in China. Control subjects, who had no history of dust or gas exposure, were selected from a paper-packing plant in the same city. Forced expiratory maneuvers were conducted in the same manner in both 1982 and 1987. The jute workers' pulmonary functions, i.e., forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1.0), and forced expiratory flow (FEF25-75%), were more compromised than were pulmonary functions in the controls for the same 5-y period; however, only the increased incidence of abnormal FEV1.0s in jute workers was statistically significant. Male jute workers had significantly higher annual decrements of FVC, FEV1.0, and FEF25-75% than did control workers. Regression analysis indicated that in 1987, predicted values of FEV1.0 and FEF25-75% for the jute workers were related to years of employment. Our results suggest that long-term exposure to jute dust could produce chronic loss of lung function.

Adult↗
PubMedDate not supplied

Long-term exposure of adults to outdoor air pollution is associated with increased airway obstruction and higher prevalence of bronchial hyperresponsiveness.

The authors studied the association between long-term exposure (i.e., > 10 y) to outdoor air pollution and the severity of obstructive pulmonary disease and prevalence of bronchial hyperreactivity to beta2 agonists in two groups of adult patients who were of similar ages and who had similar smoking habits. The subjects lived in downtown districts or in the outer suburbs of Marseilles, the neighborhood that contained air samplers. The regions were similar with respect to sulfur dioxide levels, but levels of nitric oxides and particulate matter (10 millimeters or less) were higher in the downtown area than the suburbs. The authors assessed airway obstruction, as determined by a decrease in forced expiratory volume in 1 s, mean forced expiratory flow measured between 25% and 75% of vital capacity, and an elevated value of central airway resistance. The authors tested the changes in these variables induced by inhalation of a beta2 agonist. Baseline lung function was altered more significantly in both male and female patients who lived in downtown Marseilles than in those who resided in the suburbs, and the differences persisted regardless of the season during which the study occurred. Prevalence of bronchial hyperreactivity and symptoms of asthma (but not of rhinitis) were higher in the downtown than suburban male subjects. The results of this study suggest that an association exists between actual environmental exposure to outdoor air pollution (i.e., nitrogen oxides and/or particulate matter of 10 millimeters or less) and respiratory effects in sensitive adults represented by patients with chronic obstructive pulmonary disease or asthma.

Adult↗
PubMed1999

Comparative pharmacodynamic-pharmacokinetic correlation of oral sustained-release theophylline formulation in adult asthmatics.

A sustained-release formulation of theophylline with an innovative release mechanism was evaluated in adult asthmatics. The pharmacodynamics and pharmacokinetic behavior of this formulation was compared with a market formulation (Theobid). The formulations, each containing 200 mg of anhydrous theophylline, were evaluated in six male subjects, 40-55 years of age, 151-169 cm in height, 41-60 kg in weight, who were nonsmokers with moderate chronic obstructive pulmonary disease (COPD); the study was a randomized, single-dose, open, complete crossover study with an interval of 1 week. Written consent was obtained from the patients prior to the trial. Plasma samples were obtained at 0, 1, 2, 4, 6, 8, 10, and 12 hr postadministration. Pulmonary functions were simultaneously recorded using an Erich Jaeger spirometer. Plasma theophylline assays were performed using high-performance thin-layer chromatography (HPTLC). Individual bioavailability parameters were obtained using the S-Inv computer program. Pharmacodynamic-pharmacokinetic correlation was studied using the Excel 95 version 7.0 Regression Statistics program. The test formulation (innovator) was found to be comparable with the marketed product with respect to tmax, t1/2 and Kel (p < .05). A significant difference in the means of Cmax and AUC0-12 between the innovator and the market formulation indicated a superior extent of absorption from the innovator formulation. A good pharmacodynamic-pharmacokinetic correlation was observed when plasma theophylline concentration was compared with forced expiratory volume.

Administration, Oral↗
PubMedDate not supplied

Reversibility test in the early stages of bronchial asthma.

In the early stages of bronchial asthma, it is frequent to find subjects with a positive history and an FEV1 or FEV1/FVC > 80% of the predicted value. This study investigated if the test of reversibility showed a reversible airway obstruction (RAO) in 291 subjects with the above clinical and functional features. Forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and expiratory flows (PEF, MEF50, FEF(25-75)) were registered before and 20 minutes after salbutamol administration (200 mcg by MDI). Of 291 subjects, FEV1 increased in 73 (25%) after bronchodilator > or = 12% compared to baseline; the number of subjects with a > or = 35% increase in MEF50 or FEF(25-75) were similar in terms of percentage (respectively, 29.2% and 29%), whereas those with increases in FVC (> or = 12%) and in PEF (> or = 15%) were significantly lower (respectively, 2.7% and 12.3%). The percentage of subjects with RAO (FEV1 increase after bronchodilator > or = 12%) was lower (12%) in the subgroup (108 subjects), with an MEF50 > or = 70% of the value predicted at the baseline assessment, and higher (36%) in the subjects of the subgroup (183 subjects) with an MEF50 < 70%. In conclusion, it is advisable to carry out reversibility tests in all subjects with symptoms indicative of asthma even if their functional tests are "normal" because in a considerable number of cases the RAO was found to confirm the suspected diagnosis and provided a more reliable classification of the disease.

Adrenergic beta-Agonists↗
PubMed1989

The effect of domestic factors on respiratory symptoms and FEV1.

This study was conducted to determine whether indoor air pollution factors affected respiratory function and symptoms in 1357 non-smoking Caucasian children. Interviews were conducted to determine: exposure to pets and to gases, vapours and dusts from hobbies; the use of gas stoves; fireplaces, air conditioners and humidifiers; type of heating systems; and the number of residents, and the number of smokers in the home. The forced expiratory volume in one second (FEV1) was obtained from maximum expiratory flow volume curves, and symptoms from the application of a standardized questionnaire. Indoor pets and the use of fireplaces and humidifiers had no consistent relationships with FEV1 when considered individually or in combination with the other factors. Hobbies, the use of gas stoves, the absence of air conditioning, the use of hot water heating, crowded homes, and the presence of smokers in the home all had negative relationships with FEV1. The largest effect on lung function was observed in children from homes with hot water heating systems, whereas the smallest effect was observed in children with smokers in the home. Children who lived in homes with hot water heating systems with no air conditioning had mean FEV1 of up to 0.4 litres lower than did their counterparts who lived in homes with forced air heating and air conditioning. Pets, heating systems, cooking fuel, crowding and passive smoking showed no consistent effects on the reporting of any of the symptoms. Girls who were exposed to the emissions from indoor hobbies reported more phlegm, wheeze and dyspnoea.

Adolescent↗
PubMed2006

Across-shift lung function variation in cottonseed oil workers.

BACKGROUND: The effects of cotton dust on pulmonary function among workers employed in cotton-spinning mills are well known. However, little data exist on the prevalence of this disorder in 'non-textile' cotton industries, including cottonseed oil mills, where high levels of exposure to dust have been demonstrated. AIMS: This study was performed in order to determine the across-shift and across-week decline of FEV(1) and respiratory symptoms among workers in a cottonseed oil mill. METHODS: Sixty-six exposed and 48 unexposed workers of a cottonseed oil mill in Turkey were investigated by questionnaire and lung function test (LFT). LFTs were performed before and after shift on all the working days of the week. Acute airway response was defined as an across-shift decline in FEV(1) of 5% or more on the first working day. RESULTS: Smoking was the only risk factor for having respiratory symptoms. Acute airway response was more frequently observed in the exposed group as compared to the unexposed group (OR = 6.2, 95% CI = 2.3-16.7). The median across-shift decline in FEV(1) on the first day (120 ml) significantly improved on the following days (10, 50, 60 and -30 ml). CONCLUSION: Smoking appears to be the main risk factor for having respiratory symptoms. Cottonseed dust may cause an acute pulmonary function decline on the first working day, but not on the following days of the week. This decline is associated with respiratory symptoms in exposed workers.

Adult↗