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G Viegi

Publications and source records attributed to G Viegi.

At least 37 records · Page 2Linked to original sources
PubMed2002

Longitudinal changes of body mass index, spirometry and diffusion in a general population.

The aim of this study was to evaluate the effects of body mass index (BMI) changes over an 8-yr follow-up, on longitudinal changes of vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and carbon monoxide diffusing capacity of the lung (DL,CO) indices in a general population sample of North Italy. To avoid including weight changes possibly related to physical growth, only the 1,426 adults (>24 yrs, 46% males) with complete follow-up were selected. Median linear regression models were applied to estimate the medians of change (computed as follow-up minus baseline values) of VC, FVC, FEV1 and DL,CO indices, as functions of changes of BMI over the follow-up period, separately by sex, after considering several potential confounders and effect modifiers. The extent of lung function loss tended to be higher among those who, at baseline, reported greater BMI values. Males experienced larger losses than females (20 and 16 mL FEV1 median reduction for a BMI unit increase in males and females, respectively). Conversely, longitudinal changes of BMI caused a slight and nonsignificant increase in DL,CO values in both sexes. Over an 8-yr follow-up, the detrimental effect of gaining weight might be reversible for many adults as most of those who reduced their body mass index values also increased their lung function. Overweight patients with ventilatory impairment should be routinely encouraged to lose weight for improving their lung function.

Adult↗
PubMed2001

Characteristics of women exposed and unexposed to environmental tobacco smoke (ETS) in a general population sample of North Italy (Po River Delta epidemiological study).

To define qualitative and quantitative categories of exposure to environmental tobacco smoke (ETS) and to assess possible differences for life-style factors between exposed and unexposed women, we studied 867 nonsmoking women (8-73 aged), selected from a general population sample living in the Po Delta area (near Venice, North Italy). Information was collected by a standardized questionnaire. ETS exposure at home, at work or elsewhere was considered. There was a prevalence of ETS exposure of 46% in the whole sample; the rate had a negative association with age. Exposure to ETS occurred more frequently at home, either singly (56%) or in combination with school/work and other places (75%). Exposed women were significantly younger, taller and lighter than those unexposed. Logistic regression on 20+ aged women showed that single-separated-widowed, workers, women living in a rental house, and women with a central forced air heating were significantly more exposed to ETS. Crowding index (n inhabitants/n rooms of the house) was significantly higher in those exposed. These results indicate that ETS exposure is quite frequent in Italian women and that some life-style factors (e.g. marital status or occupational status or some home characteristics), should be considered in the study of relationship between passive smoking and respiratory health.

Adolescent↗
PubMed2001

The Po River Delta epidemiological survey: reference values of total serum IgE levels in a normal population sample of North Italy (8-78 yrs).

The aim of this paper was to define, for the first time in Italy, normal levels of total serum IgE in a general population sample of North Italy. Total serum IgE in 1905 subjects, living in Po Delta area (near Venice), were measured by PRIST method. Normal values were derived from 558 subjects without asthma and/or asthmatic/rhinitic symptoms, noncurrent smokers, skin prick-test negatives ('normals'). Cut-off values to differentiate 'normals' from the remaining part of the sample ('others'), from asthmatic, and from rhinitic subjects, were established with the IgE value midway between the upper limit of the 95% confidence intervals (CI) of the geometric mean for 'normals' and the lower limit for 'others', asthmatics, and rhinitics, respectively. Geometric mean of normal children-adolescents was 45 kU/L (SD: 2.6; 95% CI: 38-63). In normal adults geometric mean was 29 kU/L (SD: 3.3; 95% CI: 25-40) in males and 19 kU/L (SD: 3.8; 95% CI: 16-22) in females. The diagnostic sensitivity of IgE test was low, while the specificity was very high. A good positive predictive value in discriminating 'normals' from 'others' was found, on the contrary, we found a good negative predictive value in discriminating 'normals' from asthmatics or from rhinitics. In conclusion, our results confirm that it is necessary to provide separate total serum IgE reference values for what concerns age in children-adolescents and in adults, and gender, in adults. Low serum IgE are helpful to exclude allergic asthma or rhinitis level of total.

Adolescent↗
PubMed2001

Epidemiology of chronic obstructive pulmonary disease (COPD).

Chronic Obstructive Pulmonary Disease (COPD) is one of the leading causes of morbidity and mortality in the industrialized and the developing countries. During 1997, COPD has been estimated to be the number four cause of death after cardiovascular diseases, tumors and cerebrovascular diseases in the United States. In 2020 COPD will probably become the third leading cause of death all over the world, following the trend of increasing prevalence of lung cancer. The impact of this respiratory disease worldwide is expected to increase with a heavy economic burden on individuals and society. In the United States direct and indirect costs of COPD were estimated at about USD24 billion in 1993. Unfortunately, there are few data on health-care utilization despite the great interest in COPD among researchers. As all chronic diseases, the prevalence of COPD is strongly associated with age. Data collected in a general population sample (living in Italy) showed a progressive increase of the prevalence of chronic bronchitis and emphysema with age, both in males and in females. COPD is determined by the action of a number of various risk factors either singly or interacting among themselves in a synergistic way. Among these, the most important is cigarette smoking, ranking at the first level for developing chronic bronchitis and emphysema. Also air pollution and some occupational exposures represent risks for developing COPD. Many epidemiological studies have indicated an association between the prevalence of chronic bronchitis and a low socioeconomic status. Furthermore, in the etiology of COPD we must consider endogenous risk factors such as gender, genetic features, presence of respiratory troubles in childhood, and family history. To date, epidemiologic studies have been of great importance for the characterization of the disease at a population level, indicating possible causes and assessing its impact on the individual and on society as a whole. Unfortunately, international standards for the diagnosis of COPD are lacking, which complicates the organization of appropriate epidemiological surveys.

Adult↗
PubMed2001

An 8-year follow-up of carbon monoxide diffusing capacity in a general population sample of northern italy.

STUDY OBJECTIVE: Diffusing capacity of the lung for carbon monoxide (DLCO) is frequently assessed as part of a thorough pulmonary function assessment in patients with pulmonary or cardiopulmonary diseases. However, little information regarding the longitudinal trends of DLCO is available. In this study, we examined the temporal trends in DLCO to determine the effects of smoking and changes in smoking habits. DESIGN: A longitudinal study was recently conducted in the Po River Delta area of northern Italy, in which DLCO measurements were taken approximately 8 years apart in the same subjects; this offered the unique opportunity to assess the temporal changes in DLCO. The longitudinal DLCO data were analyzed independently in two age groups (20 to 40 years, and > or = 40 years) using a repeated-measures analysis. RESULTS: Included were 928 subjects > 20 years old who had DLCO assessments both at baseline and follow-up. Male subjects had higher mean levels of DLCO than female subjects in the older age group (> or = 40 years). Continuous smokers had significantly lower DLCO levels than "never-smokers," but their changes in DLCO during follow-up were the same. This suggests that the lung damage due to smoking had occurred prior to DLCO testing. We also found that the annual decline in DLCO accelerated with age in adults > or = 40 years old. CONCLUSIONS: We conclude that in adults > or = 40 years of age from the general population, DLCO accelerates downwards regardless of gender, smoking, and initial FEV(1) level.

Adult↗
PubMed2001

Smoking reduction in smokers compliant to a smoking cessation trial with nicotine patch.

The aim of this retrospective analysis was to assess the extent of smoking reduction in smokers who were compliant to a smoking cessation trial with nicotine patch, and failed to completely quit smoking. Out of 297 smokers in total, 237 participants received active treatment (60 received placebo). Eighty treated subjects attended all the scheduled visits and were classified as either abstainers (nonsmokers), regular smokers or occasional smokers. Compared to the remaining 157 participants, these 80 subjects had significantly lower mean baseline daily cigarette consumption (24 versus 30; p < 0.001), expired carbon monoxide levels (25 versus 33 ppm; p < 0.001), plasma nicotine and cotinine levels, and Fagerström Tolerance Questionnaire score (5.7 versus 7.0; p < 0.001). All subjects received active treatment for up to 18 weeks (full dose for 12 weeks plus tapering dose for 6 weeks), with follow-up visits scheduled up to 1 yr. A statistically significant reduction in cigarette consumption (versus baseline) was observed among both the occasional (-99%) and regular (-77%) smokers between week 1 and week 52 (p < 0.001). Concomitant smoking and patch use was well tolerated since adverse events were infrequent, mild and transient. Thus, in addition to those subjects who successfully quit smoking, a further group of subjects who attended all the follow-up visits during the smoking cessation trial significantly reduced their mean daily cigarette consumption.

Administration, Cutaneous↗
PubMed2001

Exposure to environmental tobacco smoke is associated with lower plasma beta-carotene levels among nonsmoking women married to a smoker.

We evaluated the association between exposure to environmental tobacco smoke (ETS) from husbands who smoke and plasma levels of antioxidant vitamins among nonsmoking women. A total of 1249 women from four areas in Italy answered a self-administered questionnaire, reported their diets on a food frequency questionnaire, had a medical examination, and gave their blood for alpha and beta-carotene, retinol, L-ascorbic acid, alpha-tocopherol, and lycopene determinations. Urinary cotinine was used to evaluate the level of recent exposure to ETS. After adjusting for study center, age and education, we found no association between ETS exposure and daily nutrient intake of beta-carotene, retinol, L-ascorbic acid, and alpha-tocopherol. However, we found an inverse dose-response relationship between intensity of current husband's smoke and concentrations of plasma beta-carotene and L-ascorbic acid. The associations remained even after controlling for daily beta-carotene and vitamin C intake and for other potential confounders (vitamin supplementation, alcohol consumption, and body mass index). Moreover, when urinary cotinine was considered as the exposure variable, a significant inverse association with plasma beta-carotene was found. The findings may be of interest to explain the biological mechanism that link ETS exposure with lung cancer and ischemic heart diseases.

Adult↗
PubMed2000

Inter-laboratory comparison of flow-volume curve measurements as quality control procedure in the framework of an international epidemiological study (PEACE project).

The aim of this work was to describe the results of a simple quality control procedure for the flow-volume curve adopted in a multicentre epidemiological study (PEACE). In 14 centres, 8-15 individuals (n = 157) performed forced vital capacity (FVC) manoeuvres following a standard protocol with both the local spirometer/pneumotachograph and a portable spirometer (i.e. the 'reference instrument' for this study). Deviances of measurements were assessed by computing the differences (delta) between the former and the latter, the ratios of such differences on portable spirometer values (delta %) and the coefficients of variation (CV). The portable spirometer yielded lower mean AFVC and deltaFEV1 (forced in 1 sec) than local instruments (except for two and four centres, respectively). In most instances, differences were statistically significant. Absolute mean A%FVC ranged from 4.9-18.2%, while delta%FEV1 ranged from 2.3-18.5%. The Bland and Altman analysis showed a good agreement between the portable and local instruments, except for two centres, where a systematic trend towards higher individual absolute deltaFVC and deltaFEV1 was observed. The overall variability, assessed by CV, was within 6.2% and 5.1% for FVC and FEV1, respectively: it was similar to other quality control studies ranging from 2.0-5.5% for FVC and 2.2-5.8% for FEV1. Our results point out the importance of performing interlaboratory comparisons as a quality control procedure in multicentre epidemiological studies on lung function, and of stimulating manufacturers to extend the accuracy and precision of the instruments.

Adolescent↗
PubMed2000

Smooth reference equations for slow vital capacity and flow-volume curve indexes.

We derived reference values for slow vital capacity (VC) and flow-volume curve indexes (FVC, FEV(1), and flows) from the 1,185 tracings provided by 1,039 "normal" subjects who participated in one or both cross-sectional surveys of the Po River Delta study in 1980-1982 and in 1988-1991. Definition of "normal" was based on negative answers to questions on respiratory symptoms/diseases or recent infections, current/past tobacco smoking, and work exposure to noxious agents. Reference equations were derived separately by sex as linear regressions of body mass index (BMI = weight/height(2)), BMI-squared, height, height-squared, and age. Age entered all the models by natural cubic splines using two break points, except for the ratios FEV(1)/VC and FEV(1)/FVC. Random effects models were applied to adjust for the potential intrasubject correlation. BMI, along with height and age, appeared to be an important predictor, which was significantly associated with VC, FEV(1), FVC, FEV(1)/FVC, and PEF in both sexes, and with FEV(1)/VC and FEF(25-75) in females. Natural cubic splines provided smooth reference equation curves (no "jumps" or "angled points") over the entire age span, differently from the conventional reference equations. Thus, we recommend the use of smooth continuous equations for predicting lung function indexes, along with the inclusion of BMI in the equations.

Adolescent↗
PubMed2000

Characteristics of nonsmoking women exposed to spouses who smoke: epidemiologic study on environment and health in women from four Italian areas.

The aim of this study was to evaluate whether risk factors associated with cardiovascular or respiratory diseases and lung cancer occur differently among nonsmoking women in Italy with and without exposure to environmental tobacco smoke (ETS) from husbands that smoke. We performed a cross-sectional study of 1,938 nonsmoking women in four areas of Italy. Data on respiratory and cardiovascular risk factors and on diet were collected using self-administered questionnaires. Medical examinations and blood tests were administered; urine cotinine levels were measured. Nonsmoking women ever exposed to husbands' smoking were compared with unexposed women for several factors: education, husband's education, household crowding, number of children, current or past occupation, exposure to toxic substances at work, parental diseases, self-perceived health status, physician-diagnosed hypertension, hypercholesterol, diabetes, osteoporosis, chronic respiratory diseases, blood pressure medications, lifestyle and preventive behaviors, dietary variables, systolic and diastolic blood pressure, body mass index, waist-hip ratio, triceps skin folds, plasma antioxidant (pro-) vitamins (- and ss-carotene, retinol, l-ascorbic acid, -tocopherol, lycopene), serum total and HDL cholesterol, and triglycerides. Women married to smokers were more likely to be less educated, to be married to a less educated husband, and to live in more crowded dwellings than women married to nonsmokers. Women married to smokers were significantly less likely to eat cooked [odds ratio (OR) = 0.72; 95% confidence interval (CI), 0.55-0.93] or fresh vegetables (OR = 0.63; CI, 0.49-0.82) more than once a day than women not exposed to ETS. Exposed women had significantly higher urinary cotinine than unexposed subjects (difference: 2.94 ng/mg creatinine). All the other variables were not more prevalent among exposed compared to unexposed subjects. The results regarding demographic factors are easily explained by the social class distribution of smoking in Italy. A lower intake of vegetables among exposed women in our study is consistent with the available literature. Overall, our results do not support previous claims of more frequent risk factors for cardiovascular and pulmonary diseases among ETS-exposed subjects. In Italy, as elsewhere in Europe and North America, women who have never smoked but are married to smokers are likely to be of lower social class than those married to never-smokers. However, once socioeconomic differences are considered, the possibility of confounding in studies on the health effects of ETS is minimal.

Adult↗
PubMed2000

Prevalence of airways obstruction in a general population: European Respiratory Society vs American Thoracic Society definition.

STUDY OBJECTIVES: To evaluate the distribution of airways obstruction in a general population sample. METHODS: Cross-sectional epidemiologic survey of a general population sample living in Po Delta area (North Italy). Data on respiratory symptoms, diseases, and risk factors were collected through standardized interviewer-administered questionnaires. Lung function tests were performed, with criteria for defining airways obstruction based on the 1995 European Respiratory Society (ERS) statement (FEV(1)/vital capacity ratio < 88% predicted and < 89% predicted in men and women, respectively), "clinical" criteria (FEV(1)/FVC ratio < 70%), and the 1986 American Thoracic Society (ATS) statement (FEV(1)/FVC ratio < 75%). RESULTS: A total of 1,727 subjects aged > 25 years investigated from 1988 to 1991 were included. Prevalence rates of airways obstruction for subjects 25 to 45 years old and subjects >/= 46 years old were as follows: ERS, 10.8% and 12.2%; clinical, 9.9% and 28.8%; and ATS, 27% and 57%, respectively. When considering only moderate/severe obstruction, the rates were as follows: ERS, 0.4% and 3.6%; clinical, 0.3% and 4.4%; and ATS, 0.5% and 5.2%, respectively. The trend was confirmed after stratifying for smoking habit and the presence/absence of respiratory symptoms/diseases. The highest specificity and predictive value for any respiratory symptom/disease was shown by the ERS, and the lowest was shown by the ATS criterion, while the reverse was true for sensitivity; overall accuracy was slightly lower for the ATS criterion. Multiple logistic regression models indicated a higher number of significant associations with known risk factors for airways obstruction according to clinical and ATS criteria than ERS criterion. CONCLUSIONS: The prevalence of COPD in a general population depends very much on the criterion used for definition of airways obstruction. Further research is needed to reach a standardized and epidemiologically consistent criterion for airways obstruction.

Adolescent↗
PubMed1999

Dyspnoea is associated with pulmonary function impairment in exposed workers.

This study aimed to evaluate the prevalence of dysponea and its predictors in studies on several working male groups in British Columbia (BC), Canada (cedar sawmill, grain elevator, pulpmill, and aluminum smelter workers), and Tuscany (T), Italy, (shoe and furniture makers, millers, bakers, and pharmaceutical workers). We performed cross-sectional health studies (interviews and pulmonary function tests) for 2498 BC and 1474 T workers exposed to air contaminants, and 1110 BC and 243 T controls. Similar questionnaires and the same definitions were used in BC and in T. Pulmonary function tests were also performed. The participation rates were >92% in BC workers and 82% in T workers. The overall prevalence of moderate dyspnoea was not different in exposed BC and T workers in comparison with controls. Slight dyspnoea was significantly more frequent in BC workers, but not in T workers, with respect to controls. After adjusting for age, body mass index (BMI), smoking, current asthma, and chronic bronchitis, forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were found to be significantly associated with slight and moderate dyspnoea in BC workers, and slight dyspnoea in T workers. Isolated dyspnoea is associated with reduction in FEV1 and FVC in working populations, after adjusting for potentially confounding variables.

Adult↗
PubMed1999

Differences in parental- and self-report of asthma, rhinitis and eczema among Italian adolescents. SIDRIA collaborative group. Studi Italiani sui Disordini Respiratori dell' Infanzia e l'Ambiente.

Epidemiological and clinical information on respiratory and allergic disorders in adolescents has been collected from the adolescents themselves or from their parents, but little is known about the differences between these two sources of information. This study compared the responses to 10 identically worded questions from the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire on asthma, rhinitis and eczema between written self- and parent-completed questionnaires in a large sample of 21,068 adolescent Italians aged 13-14 yrs. The effects of sex, latitude of residence, urbanization, socioeconomic status, previous diagnosis of asthma, family history of allergic diseases and adolescent's smoking habits on the prevalence estimates obtained with the two questionnaires were analysed using multiple logistic regression. Prevalence of self-reported symptoms was significantly higher in self-reported for all questions except for lifetime eczema, which was higher in parental report. Agreement between the two sources of information was poor, although it was slightly better for questions relative to clinical diagnosis of asthma, hay fever or eczema than for related symptoms, and for respiratory with respect to cutaneous disorders. When compared with self-reported, parent-reported was consistently higher in males and was more affected by socioeconomic level and by a diagnosis of asthma or family history of allergic diseases, whereas self-reported was more sensitive to the effect of the adolescent's smoking habits. It is concluded that, in adolescents, parent- and self-reported respiratory and allergic symptoms differ significantly and are differently affected by several constitutional and environmental factors. Obtaining direct information from adolescents may be essential for a correct evaluation of respiratory symptoms.

Adolescent↗
PubMed1999

The impact of parental smoking on asthma and wheezing. SIDRIA Collaborative Group. Studi Italiani sui Disturbi Respiratori nell'Infanzia e l'Ambiente.

To evaluate the impact of parental smoking on childhood asthma and wheezing, we studied two random samples of subjects ages 6-7 and 13-14 years in ten areas of northern and central Italy. Standardized questionnaires were completed by parents of 18,737 children and 21,068 adolescents (response rates, 92.8% and 96.3%, respectively) about their smoking habits and the respiratory health of their children. Adolescents were asked about their respiratory health and personal smoking. We compared two groups of cases with healthy subjects: (1) "current asthma" (children, 5.2%; adolescents, 6.2%) and (2) "current wheezing" not labeled as asthma (children = 4.5%, adolescents = 8.5%). Exposure to smoke of at least one parent increased the relative risk of current asthma among children [odds ratio (OR) = 1.34; 95% confidence interval (CI) = 1.11-1.62] and of current wheezing among adolescents (OR = 1.24; 95% CI = 1.07-1.44). Maternal smoking had a stronger effect than paternal smoking. Maternal smoking during pregnancy was associated with current asthma (OR = 1.62; 95% CI = 1.34-1.96) and current wheezing in children (OR = 1.31; 95% CI = 1.06-1.62); the effects were lower among adolescents. Among subjects with a negative history of parental asthma, maternal smoking was associated with current wheezing in both age groups, whereas among those with a positive history of parental asthma it was associated with current asthma in children, but not in adolescents. We estimated that 15% (95% CI = 12-19) of the current asthma cases among children and 11% (95% CI = 8.3-14) of the current wheezing cases among adolescents are attributable to parental smoking in Italy.

Adolescent↗
PubMed1999

Selection of reproducible forced expirograms: percentage or fixed-volume criterion.

The aim of this study was to evaluate whether the intrasession reproducibility of forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) depends on height and lung volume. FVC tracings of 740 subjects (350 males) from a general population sample living in North Italy were analyzed. Subjects filled out a standardized questionnaire and performed three acceptable FVC maneuvers following the American Thoracic Society recommendations. The differences between the largest and the second largest FVC and FEV1 were computed as absolute (DeltaFVC, DeltaFEV1) and as percentage values (DeltaFVC%, DeltaFEV1%). The higher the tertiles of the largest FVC and FEV1 were, the higher were DeltaFVC and DeltaFEV1. Regarding FVC, borderline differences in both sexes for DeltaFVC and in males significant differences for DeltaFVC% were found among the tertiles. Regarding FEV1, in both sexes DeltaFEV1 significantly differed among the tertiles. DeltaFVC and DeltaFEV1 correlated with height and lung volume in both sexes, except for DeltaFVC versus the largest FVC in females. When DeltaFVC and DeltaFEV1 were analyzed with respect to respiratory symptoms/diseases and smoking habit, no significant differences were observed in both sexes, except for DeltaFEV1 between ever- and never-smoking males. It may be concluded that the intrasession within-subject variability of FVC and FEV1 is proportional to lung volume and height, regardless of the sex, presence of symptoms and smoking habit. Thus, our results confirm the usefulness of a reproducibility criterion based on a percentage rather than on a fixed volume.

Adolescent↗
PubMed1999

Prevalence rates of respiratory symptoms and diseases in general population samples of North and Central Italy.

SETTING: Four cross-sectional general population surveys in Italy: northern rural Po Delta area (1980-1982, n = 3284; 1988-1991, n = 2841), and central urban Pisa area (1985-1988, n = 3865; 1991-1993, n = 2841). OBJECTIVE: To analyse changes in prevalence rates of respiratory symptoms and diseases. DESIGN: Prospective epidemiological studies by standardised interviewer-administered questionnaire. RESULTS: Prevalence rates of respiratory symptoms and diseases tended to be higher in males (except for dyspnea and pleuritis), in the urban area (more polluted), and in the second surveys; moreover, they increased with age. Asthma peaked in those aged under 25 years and over 64 years. The highest prevalence rates were shown by current smokers of both sexes for all respiratory symptoms and by ex-smoker males for all respiratory diseases, while female current smokers reported chronic bronchitis, emphysema and asthma more frequently. The most clear-cut trend towards increase between the two surveys within each area was exhibited by wheeze and asthma. CONCLUSIONS: These findings highlight the relevance of sex, age and smoking habit, as well as the possible effects of air pollution, in relation to respiratory symptoms. They also indicate a trend towards an increase in asthma symptoms in Italian general population samples in the 1990s, and an under-estimate of medically diagnosed chronic respiratory diseases.

Adolescent↗