Biomedical subjects
Publications and source records attributed to G Viegi.
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In order to assess the role of genetic factors and environmental influences in bronchial responsiveness, we studied the airway response to an inhaled bronchodilator in 66 nonasthmatic parents (age, 30.9 +/- 5.9 years) of infants with bronchiolitis (group 1). It was a placebo-controlled double-blind study. A control group (group 2) of healthy parents of infants who did not have bronchiolitis also were investigated with the test of bronchodilator response. All subjects showed normal expiratory airflow and lung volumes (forced vital capacity [FVC], forced expiratory volume in 1 s [FEV1], and mean forced expiratory flow during the middle half of FVC [FEF25-75%] > 80 percent of predicted) at baseline forced expiratory maneuver. In 16 (24.2 percent) subjects of group 1, there was significant increase in at least one parameter after salbutamol administration, but not after placebo inhalation, with respect to baseline levels. Furthermore, no significant changes in FVC, FEV1, or FEF25-75% values were found in group 2. In conclusion, this study confirms that parents of infants with bronchiolitis have an enhanced airway responsiveness, greater than control parents. Further studies are needed to assess whether one may infer the outcome of infants with bronchiolitis from this characteristic in their parents.
In order to assess the distribution of asthma in Italy in the 1980s, we have compared the findings of three general population surveys carried out in the North and the Centre of the country. Two cross-sectional investigations were performed in the Po Delta area (North Italy), 6 yrs apart: 1) 3,285 subjects, aged 8-64 yrs, in 1980-1982 (PD1); and 2) 2,841 subjects, aged 8-73 yrs, in 1988-1991 (PD2). One cross-sectional survey was carried out in Pisa (Central Italy): 3,866 subjects, aged 5-90 yrs, in 1985-1988 (PI1). For this analysis we have used data from the standardized questionnaires of those subjects between 18-64 yrs, who were currently employed. The prevalence rate of ever asthma was 3.3-5.5%, that of current asthma 1.3-2.9%; almost all of the diagnoses were confirmed by a doctor. Taking into account only doctor-confirmed asthma, the age of onset of manifestations was most frequently over 18 yrs (41-79%). It also occurred more frequently after the onset of employment. As regards smoking, whilst most asthmatic males were current or former smokers (70-86%), most asthmatic females were nonsmokers. However, the situation changed in PD2, where females showed the same pattern as males. Considering asthmatic subjects with skin-prick test reactivity (data available only in PD2), the vast majority (67% in males, 75% in females) had an age of disease onset under 18 yrs. In conclusion, the prevalence of asthma in Italy in the 1980s was similar to that in other European countries and was affected by atopy and smoking differently in the two sexes.(ABSTRACT TRUNCATED AT 250 WORDS)
Two thousand eight hundred and forty one subjects, aged 8-73 yrs, took part in the second cross-sectional survey in the Po River Delta area: among them, a subsample of currently employed people, aged 14-71 yrs, was chosen to establish the relationship between occupational exposure to dusts, chemicals or gases and respiratory symptoms, lung function and bronchial reactivity. Each subject filled out the Italian National Research Council (CNR) standardized questionnaire concerning respiratory symptoms, diseases and risk factors. A variable proportion of subjects performed acceptable forced and slow vital capacity manoeuvres, diffusing capacity of carbon monoxide and bronchial challenge test to methacholine. Occupational exposure appeared to be related to prevalence rate of respiratory symptoms (wheeze, dyspnoea, presence of at least one respiratory symptom) and bronchial asthma. Consistent effects on lung function were not evident. With respect to the bronchial challenge test, using the measurement of the provocative dose producing a 20% fall in forced expiratory volume in one second (PD20) a significantly higher percentage of hyperreactive subjects was found among ex-smoker exposed men; a borderline higher percentage of hyperreactive subjects was also found in non-smoker exposed women. The study findings support the suggestion that occupational exposure may play a role in the development of airway obstructive diseases.
The single-breath carbon monoxide diffusing capacity (DLCOsb) was measured together with ventilatory lung function tests as part of a survey of a general population sample living in Northern Italy (n = 2,481). Based on answers to an interviewer-administered questionnaire, subjects free of respiratory symptoms or diseases were identified. Data from subjects who had never regularly smoked cigarettes were used to derive reference equations for the test indexes, and data from the remaining subjects who had smoked were used to derive regression equations incorporating a term expressing cigarette consumption (cube root of pack-years) and a term indicating current smoking decrement, in order to obtain expected DLCOsb percent predicted. Neither number of cigarettes smoked daily or duration of smoking, in smokers, nor duration of smoking or years since quitting smoking, in ex-smokers, entered significantly the multiple-regression model. The mean values of DLCOsb were only slightly affected by the increasing degree of airway obstruction. When subjects with confirmed asthma were analyzed, after stratifying for different levels of FEV1/FVC ratio, increased mean value of DLCOsb (over 100%) was found in those with an FEV1/FVC ratio between 75 and 65%. This cross-sectional analysis suggests that there is a decrease in DLCOsb with cumulative cigarette consumption even in healthy subjects. Further, it confirms the clinical observations of high DLCOsb values in asthmatic patients, at least in those with an initial degree of chronic airflow obstruction.
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Residual volume (RV) was obtained by subtracting vital capacity from total lung capacity determined by the single breath helium dilution (TLCsb) to measure CO diffusing capacity in 2,680 subjects (8 to 64 years old) of a general population sample. There were 712 normal subjects (243 male and 469 female subjects) selected to evaluate the pattern of RV by age and to derive reference values for internal comparisons. From 8 to 20 years old, RV showed an increase because of the cross-sectional body size effect; after 20 to 30 years, RV was still increasing, however, at a lower level. Age and height coefficients were significantly related to RV in younger and older ages, both in male and female subjects. The RV percent predicted and RV/TLC percent were higher in smokers when compared to nonsmokers and exsmokers (the difference was significant in male subjects). A dose-response effect was observed between RV percent predicted, RV/TLC percent, and pack-years. The RV percent predicted and RV/TLC percent were significantly higher in smokers and nonsmokers with FEV1 percent predicted below the normal limit (the difference was significant in male subjects). Moreover, higher values of RV percent predicted and RV/TLC percent were observed in subjects with wheezy symptoms in male smokers and nonsmokers. A negative significant correlation was observed between RV/TLC percent and the diffusing capacity adjusted for lung volume (DL/VA) in smokers, exsmokers and nonsmokers of both sexes, confirming the hypothesis that the decrease in DL/VA may be ascribed to the enlargement of terminal air spaces. In conclusion, determination of RV by the single breath helium dilution method is suitable in epidemiology, and it allows additional important information for understanding the physiopathologic mechanisms related to the pathogenesis of chronic obstructive lung disease.
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We assessed the respiratory effects of the number of cigarettes smoked daily (CIGD) in 748 male smokers of a general population sample living in the unpolluted area of the Po Delta (Italy). A standardized questionnaire, flow-volume curves (V/V), the diffusing capacity of carbon monoxide (DLCO) and the slope of the alveolar plateau of nitrogen (DN2%/l) were used. Subjects were divided according to the median value of the observed distribution of CIGD (1-19, 20+) and according to the tertile values of the observed distribution of pack-years (an index representing lifetime cigarette consumption; 1-7, 8-21, 22+). In those with a higher CIGD, the prevalence rate of chronic phlegm was always significantly increased, while the prevalence rate of wheeze was significantly higher if they had smoked 8+ pack-years. Using analysis of variance, adjusted for pack-years, DLCO indexes, FEF75-85 and Vmax75 were significantly reduced in those with higher CIGD. When multiple logistic models, accounting for the independent effects of age and pack-years, were used, significantly increased odds ratios (ORs) for symptoms (e.g. OR = 2.0 for phlegm, OR = 1.8 for cough, OR = 1.6 for wheeze) and abnormal DLCO (OR = 1.9) or DN2%/l (OR = 1.6) were associated with a daily consumption of 10 cigarettes. In conclusion, the amount of cigarettes currently smoked may add a negative effect to that caused by lifetime cigarette consumption on respiratory symptoms and lung function. Moreover, the use of diffusing capacity in general population surveys is advisable.
We assessed the effects of occupational exposure in a general population sample living in an unpolluted rural area of North Italy. In the age range of 18 to 64 yr, there were 417 participants who reported any exposure to dusts, chemicals, or gases and 1,218 who reported no exposure. Each subject completed a standardized interviewer-administered questionnaire (CNR-questionnaire). A variable proportion of participants succeeded in performing flow-volume curves, diffusing capacity of carbon monoxide, and slope of alveolar plateau of nitrogen. There was no significant difference for symptom prevalence rates between exposed and nonexposed in men and women who smoke. In nonsmoking women, those exposed showed significantly higher prevalence rates for exertional dyspnea and asthma. Regarding lung function, in exposed male smokers there was a significantly higher slope of the alveolar plateau. In exposed female nonsmokers, FEV1 and forced expiratory flows were significantly lower. Multiple logistic models in the overall group, accounting for age, smoking, and pack-years, showed that work exposure was associated significantly with higher risks for all symptoms in men (e.g., odds ratio: 2.76 for dyspnea, 2.31 for asthma, 1.69 for cough, and 1.64 for phlegm); in females, the association was significant for dyspnea (OR = 3.74) and asthma (OR = 3.29). Exposed men also had a significantly higher risk for %FEV1 or FEV1/FVC% below 70 (OR = 1.45). Our findings confirm those of the other few epidemiologic surveys in general population samples and contribute to the suggestion of a causal association between occupational exposure and chronic obstructive pulmonary disease.
We surveyed two general population samples aged 8 to 64 living in the unpolluted, rural area of the Po Delta (northern Italy) (n = 3289) and in the urban area of Pisa (central Italy) (n = 2917). Each subject filled out a standardized interviewer-administered questionnaire. The Pisa sample was divided into three groups according to their residence in the urban-suburban areas and to outdoor air pollution exposure (automobile exhaust only or industrial fumes as well). Significantly higher prevalence rates of all the respiratory symptoms and diseases were found in Pisa compared with the Po Delta. In particular, rhinitis and wheezing symptoms were higher in all the three urban zones; chronic cough and phlegm were higher in the zone with the automobile exhaust and the additional industrial exposure. Current smoking was more frequent in the rural area, but the urban smokers had a higher lifetime cigarette consumption. Childhood respiratory trouble and recurrent respiratory illnesses were evenly distributed. Exposure to parental smoking in childhood and lower educational level were more frequent in Po Delta, whereas familial history of respiratory/allergic disorders and work and indoor exposures were more often reported in the city. Multiple logistic regression models estimating independently the role of the various risk factors showed significant odds ratios associated with residence in Pisa for all the symptoms but chronic phlegm. For example, those living in the urban-industrial zone had an odds ratio of 4.0 (4.3-3.7) for rhinitis and 2.8 (3.0-2.6) for wheeze with respect to those living in the Po Delta.(ABSTRACT TRUNCATED AT 250 WORDS)
Prevalence rates of respiratory symptoms and diseases in a large group of Anglos and Mexican-Americans were analyzed. Each subject completed a questionnaire. Among current smokers, chronic productive cough and dyspnea were significantly higher in both ethnic groups; wheezy symptoms were higher in Anglos. There were no significant differences in the symptom prevalence rates between the two groups, after stratifying by current cigarette consumption and CRT. The spirometric values were not significantly different. In both ethnic groups, the prevalence rates of wheeze, SOBWHZ and asthma were significantly higher in those who had CRT. Among Anglos, less educated smokers had significantly higher prevalence rates of SOBWHZ and dyspnea; nonsmokers with less education had higher prevalence rates of cough, chronic cough and dyspnea. Our results confirm the importance of CRT and lower educational level as risk factors for respiratory symptoms. Ethnicity is not associated with symptomatology or lung function impairment.
Effects of indoor pollution exposure were evaluated in a general population sample (n = 3,289) living in the Po River Delta area. Prevalence rates of chronic cough in men and dyspnoea in women were significantly higher in association with the use of bottled gas (propane) for cooking instead of natural gas (methane). Chronic cough and phlegm in men and dyspnoea in women were significantly associated with the use of a stove for heating. When combining type of heating and fuel used, in men a trend toward higher prevalence rates of chronic cough and phlegm was shown in those with stove or fan heating (regardless of the fuel); in women the trend reached statistical significance for dyspnoea. The relationship between stove (regardless of fuel) and decrease in forced expirograms was statistically significant only in women. In multiple logistic models, accounting for independent effects of age, smoking, pack-years, parents' smoking, socio-economic status, body mass index, significantly increased odds ratios were found in males for the associations of: bottled gas for cooking with cough (1.66) and dyspnoea (1.81); stove for heating with cough (1.44) and phlegm (1.39); stove fuelled by natural gas and fan or stove fuelled other than by natural gas with cough (1.54 and 1.66). In females, significantly increased odds ratios were found only for dyspnoea when associated with bottled gas for cooking (1.45), stove for heating (1.46), stove fuelled by natural gas (1.58), stove or fan fuelled other than by natural gas (1.73).(ABSTRACT TRUNCATED AT 250 WORDS)
A longitudinal study on chronic obstructive lung disease (AOD) has been started in the Po River Delta in northern Italy. The first cross-sectional study was conducted in this previously unpolluted rural area before the start of operation of a large thermoelectric power plant (2,649 megawatt). A significant output of air pollutants is expected. This will permit us to carry out a "natural experiment" to study the effects of air pollutants (SO2 and suspended particulates). A multistage stratified cluster design was chosen. Stratification was based on age and socio-economic characteristics (SES) of households, and was performed in two steps, using the different indices computed from the census data. Geographic zones represented four areas of different predicted pollution exposure, once the plant started operating. There were 3,289 subjects in the selected age group (8-64) who agreed to participate (78%); only 11% refused to participate. The participants were representative of the clusters and SES. Participants had slightly fewer employed males, who did not participate due to work. The stratification and staging method allowed us to keep an acceptable level of precision and efficiency in the sample. In fact age-related differences were not found among the SES strata and geographic zones; various socio-economic characteristics, verified from the questionnaire information, were consistent with the SES stratification. Differences between geographic zones were related to the number of households of different SES within clusters; however this reflects the characteristics of the general population in the area.
To assess the relationships among single-breath diffusing capacity for CO (DLCOsb) (13), respiratory symptoms, and cigarette smoking in a general population sample, the data of 718 men and 894 women 20 yr of age or older were analyzed, and comparisons were performed with flow-volume curve (MEFV) variables and the slope of the alveolar plateau (DN2%/L) as well. Percent predicted DLCOsb and its correction for alveolar volume (DL/VA) were significantly lower in smokers than in nonsmokers. The relationship of presence/absence of respiratory symptoms and cigarette smoking with DLCOsb and DL/VA was significant. DLCO indices were almost always selected as discriminant variables in multivariate analysis between asymptomatic and symptomatic subjects. Poor concordance among lung function tests was evident: in men, 30% with abnormal (i.e., lower than 97.5% percentile) and 21% with normal DLCO indices also had abnormal MEFV parameters and/or DN2%/L. In women, the corresponding figures were 24 and 10%, respectively. In men, when considering only DLCO indices, the percentage of symptomatic subjects with abnormal lung function tests ranged from 33% in those with at least one symptom to 45% in those complaining of dyspnea. When the proportion of symptomatic subjects with DN2%/L and MEFV abnormalities were added, it increased to 56 and 66%, respectively. However, in women the proportion of symptomatic subjects with abnormal lung function indices was very small. These results indicate the usefulness of including CO diffusing capacity in epidemiologic surveys in the detection of abnormalities.
Lung involvement in essential mixed cryoglobulinemia (EMC) has been recently described. In order to assess whether patients with EMC experience an accelerated deterioration of lung function, nineteen patients (17 females, 2 males; 49.6 +/- 6.6 years) underwent a short-term follow-up of lung function, chest X-ray and serologic investigations. Reduction of forced expiratory flows and presence of roentgenologic signs of interstitial involvement were confirmed in the baseline evaluation. In addition, a decrease of diffusing capacity was shown. After a mean interval of 15 months, no significant change in lung function was found, with the exception of decrease in maximal expiratory flow at 50% of forced vital capacity, total lung capacity, functional residual capacity, coefficient of transfer of CO. A slight decrease of hemolitic complement (CH50) and of complement fraction (C3) was also observed. This study suggests that patients with EMC tend to have an involvement of pulmonary interstitial space, possibly related to immune complex deposition, but they do not show a severe decline of lung function. Periodical assessment of lung function and chest X-ray is, however, worthwhile.
The role of childhood respiratory infections before 12 yrs of age (CRI) and during adolescence-adulthood (ARI) was studied in a general population sample (n = 3,289), living in an unpolluted area of Northern Italy. The presence of respiratory symptoms and diseases, as well as risk factors for obstructive airways disease (OAD), was assessed by a standardized questionnaire. Forced vital capacity and derived expiratory flows, and single-breath diffusing capacity were measured using computerized instrumentation. There were 1,185 (36.2%) subjects who reported pertussis (PT), 374 (11.4%) recurrent chest colds, pneumonia and croup, singly or in combination, with or without pertussis (CRI), and 1,718 (52.4%) reported no respiratory infections in childhood (NOCRI). Prevalence rates of respiratory symptoms and diseases were significantly higher in subjects of the CRI group in all ages, and in older smokers. Wheeze and attacks of shortness of breath with wheeze were significantly higher in younger nonsmoking subjects with a history of CRI. Respiratory symptoms and diseases were not more prevalent in subjects of the PT group. Prevalence rates of respiratory symptoms and diseases were significantly higher in subjects with a history of ARI, both in smokers and nonsmokers. Lung function parameters adjusted for sex, age and smoking were significantly lower in CRI subjects; PT subjects showed lower values than NOCRI subjects. A significantly higher prevalence rate of ARI was present in subjects who reported CRI, both in smokers and nonsmokers. Subjects with both CRI and ARI showed the highest prevalence of respiratory symptoms and diseases. In addition, they had the lowest lung function values regardless of smoking habit.
The prevalence rates of asthma and asthma symptoms were investigated in a general population sample (n = 3,289) living in a rural area of northern Italy. The subjects received a standard questionnaire and performed lung function tests with automated equipment. The overall prevalence rate of reported diagnosis of asthma was 5%. In young nonsmokers of both sexes the prevalence rates of reported diagnoses were higher than those of symptoms whilst the reverse occurred in older age groups. The prevalence rates decreased from childhood to young adults and increased again in older age groups. In smokers, reported diagnoses and symptoms increased with age and the prevalence rates of symptoms were always higher than those of diagnoses. Smokers with symptoms and reported diagnoses had lower lung function parameters than those with only symptoms. The distribution of asthma symptoms in our population indicates the importance of cigarette smoke and other environmental factors in the expression of the disease.