PubMed Health⌕ Search

Biomedical subjects

C Ségala

Publications and source records attributed to C Ségala.

15 recordsLinked to original sources
PubMed2003

[Factors predicting the severity and the degree of symptom control of asthma in a recently diagnosed cohort of adult patients (A.S.M.A study)].

INTRODUCTION: The aim of this cohort study was to describe the evolution of recently diagnosed (<12 months) asthma, and to identify outcome predictive factors. This paper describes the evolution of an adult cohort and the factors related to asthma severity and control. METHODS: In 1995, 251 chest specialists from throughout France, recruited 347 asthmatic adults (subjects with severe asthma were excluded). 220 eligible patients were examined every four months over a three year period. Data (socio-demographic characteristics, asthma history, results of atopy testing and lung function tests, treatment, drug compliance, respiratory infections, changes in lifestyle and environment, and major life events) were collected by means of detailed standardised questionnaires completed by physicians. Asthma severity, recorded one year after study inclusion, and asthma control, assessed at each follow-up visit in the second and third year, were defined according to the international guidelines. RESULTS: The clinical status of these adult patients generally improved rapidly. Asthma severity correlated closely with allergy, with a history of childhood asthma and with sensitisation to indoor allergens. After adjusting for severity, poor asthma control was associated with poor compliance, with respiratory infections, and, to a lesser extent, with animals inside the home. CONCLUSIONS: This cohort study highlights the association of asthma severity with allergy, and of poor asthma control with poor compliance and respiratory infections.

Adult↗
PubMed2003

[Odors and health: a descriptive epidemiological study around a wastewater treatment plant].

BACKGROUND: Following community concern regarding potential health effects associated with odors of a wastewater treatment plant, a descriptive epidemiological study was conducted to assess the complaints and the health status of the community and to identify potentially more susceptible groups. METHODS: Questionnaires were administered by telephone to nearly 3.000 subjects, randomly selected in the 8 nearby towns, using a geographical Information System. Residents of three areas were compared, according to the distance from the site: 0-1.5 km (high exposed group), 1.5-3 km (moderate exposed group) and 3-4.5 km (low exposed group). Questions measured demographic characteristics, concerns, perceived environmental risk and health effects (symptoms in the past 1 month and in the past 1 year). Multivariate logistic models study the relationships of complaints and health effects, with area and susceptibility factors. RESULTS: Two thousand eight hundred and sixty seven eligible adults participated in an interview. Taking in account confounding factors, population of high and moderate exposed groups reported more odor complaints than the low exposed group, with adjusted odds ratio (OR) of 4.73 (CI95%: 3.63-6.14) and 2.06 (CI95%: 1.59-2.66) respectively. But these 2 groups did not report more frequent health effects compared to the low exposed group. Several health effects were significantly more frequent in persons with self-reported chemical intolerance and in persons considering malodor in terms of health threat. In this last sub-group of population, rhinitis were significantly more frequent in the high exposed group compared to low exposed group, whereas respiratory infections and asthma attacks showed the same non significant patterns. CONCLUSION: If 24,2% of the total sample complaints from odors of the site, this study did not show a higher frequency of health effects in people living near the site (high exposed group). But 2 susceptible groups (with a higher frequency of symptoms potentially related to odors) were identified: persons with self-reported chemical intolerance, among those, many allergic and asthmatic subjects, and persons considering malodor in terms of health threat.

Adolescent↗
PubMed2002

Short-term health effects of particulate and photochemical air pollution in asthmatic children.

In a previous panel study in Paris, France, detrimental effects of moderately high levels of winter air pollution on the symptoms and lung function of asthmatic children were demonstrated. A new study was conducted, with the aim of assessing the short-term effects of photo-oxidant and particulate air pollution on childhood asthma during spring and early summer in Paris. Eighty-two medically diagnosed asthmatic children were followed up for 3 months. Outcomes included the incidence and prevalence of asthma attacks, nocturnal cough, supplementary use of beta2-agonists, symptoms of airway irritation, and peak expiratory flow (PEF) value and its variability. The statistical methods controlled for the lack of independence between daily health outcomes, temporal trends and pollen and weather conditions. Black smoke and nitrogen dioxide (NO2) were associated with increases in the occurrence of nocturnal cough and respiratory infections. Ozone (O3) was associated with an increase in the occurrence of asthma attacks and respiratory infections and with changes in lung function, as shown by an increase in PEF variability and a decrease in PEF. Statistically significant interactions were demonstrated between O3 and temperature and between O3 and pollen count for asthma attacks. O3 levels had a greater effect on additional bronchodilator use and on irritations of the eyes, nose and throat on days on which no steroids were used. Particulate matter was associated with eye irritation only. This study showed that, although within international air quality standards, the prevailing levels of photo-oxidant and particulate pollution in spring and early summer had measurable short-term effects on children with mild-to-moderate asthma.

Adolescent↗
PubMed2001

Air pollution and health: correlation or causality? The case of the relationship between exposure to particles and cardiopulmonary mortality.

Many epidemiologic studies have observed, in different contexts, a slight short-term relationship between particles in air and cardiopulmonary mortality, even when air quality standards were respected. The causality of this relationship is important to public health because of the number of people exposed. Our aim was to make a critical assessment of the arguments used in 15 reviews of published studies. We explain the importance of distinguishing validity from causality, and we systematically analyze the various criteria of judgment within the context of ecologic time studies. Our conclusion is that the observed relationship is valid and that most of the causality criteria are respected. It is hoped that the level of exposure of populations to these particles be reduced. In Europe, acting at the root of the problem, in particular on diesel emissions, will also enable the reduction of levels of other pollutants that can have an impact on health. In the United States, the situation is more complicated, as particles are mainly secondary. It is also essential to continue with research to become better acquainted with the determinants of personal global exposures and to better understand the toxic role of the various physicochemical factors of the particles.

Air Pollution↗
PubMed2000

Asthma in adults: comparison of adult-onset asthma with childhood-onset asthma relapsing in adulthood.

The prevalence of asthma in children and young adults is rising. Although the general features of asthma are similar in children and adults, there are several differences. Studies of the differences between childhood- and adult-onset asthma may provide new insight into the phenotypic heterogeneity of asthma. The aim of this cross-sectional study was to compare the characteristics of asthmatic adults who reported having (n = 84) or not having (n = 235) asthma in childhood. The participating patients were recruited by chest specialists throughout France and were examined from March to November 1995. The specialists completed a standardized questionnaire, and carried out a clinical examination and spirometric tests. Male sex; greater severity, particularly lower spirometry values related to small airways; greater severity and earlier onset of allergy; and maternal history of atopic dermatitis and perennial rhinitis were found to be associated with reported childhood asthma. This study exhibits highly internally consistent results and indicates that subjects who did have childhood asthma and relapse in adulthood appeared to have a potentially more severe form of asthma.

Adult↗
PubMed1997

Tumor progression and oxidant-antioxidant status.

We previously reported on a paradoxical oxidant-antioxidant status in breast cancer patients, more so in pre-menopausal than menopausal women. In this study, measurements were performed on 146 patients with various carcinomas. Vitamin E/total cholesterol increased and plasma malondialdehyde decreased with tumor size and progression. To investigate the difference between young pre-menopausal and aged menopausal breast cancer patients, the same measurements were performed in 365 breast cancer patients according to pathology, tumor size and estrogen receptors. The oxidant-antioxidant status varied with these prognosis factors in the same pattern, and was more pronounced in young than aged women.

Adult↗
PubMed1997

[Asthma in private pneumology practice].

We assessed asthma severity in patients attending private practice chest specialists, studied the factors related to classification by physicians, and described medications prescribed. 545 chest specialists scattered throughout France, included the patients examined from 3 to 28 May 1993 (N = 14,865). Besides a classification of asthma severity in four classes (mild, moderate, moderately severe, and severe), questionnaires included 20 questions on the history and characteristics of asthma, lung function level and medications prescribed. The proportion of mild asthmatics was 55% among the 3,620 children (aged 6 to 15 years), 42% among the 6,479 young adults (aged 16 to 45 years), and 18% among the 4,766 older adults (aged 46 to 75 years). Followed-up patients were considered more severe than new patients among adults, but not among children. The factors related to asthma severity were impaired FEV1, history of hospitalization, critical care and emergency visits for asthma, limitation of physical activities, and, to a latter extent, symptoms between exacerbations, frequent asthma attacks and daily use of beta 2-agonists. Anti-inflammatory drugs were prescribed to practically all patients from grade 2 (moderate): steroids increased whereas sodium cromoglycate and nedocromil decreased with increasing severity. This study provides a valuable estimate of the classification and medications prescribed to asthmatic patients examined by 50% of private practice chest specialists in France.

Adolescent↗
PubMed1996

Oxidant-antioxidant status alterations in cancer patients: relationship to tumor progression.

A significant change of vitamin E and malondialdehyde plasma concentrations was reported in breast cancer patients. This change was unexpected because vitamin E was higher and malondialdehyde lower in cases than in controls, and the difference was more significant in young rather than older women. The first aim of this study was to determine whether these changes were associated only with breast cancer, or with hormone-related cancers, and/or cancers associated with nutritional risk factors or with all types of cancers. Measurements were performed before therapy on 269 hospital-based controls and on 146 patients with various carcinomas. Vitamin E:total cholesterol increased and malondialdehyde plasma concentration decreased with tumor size and progression, without relation to the site. The second aim was to understand the difference in the change observed between young and old breast cancer patients. These analytes were measured in 365 breast cancer patients according to three prognosis factors: pathology, tumor size and estrogen receptors. Vitamin E:total cholesterol significantly decreased with estrogen receptor amount. Malondialdehyde plasma concentration decreased with severity of pathology and tumor size. Together, these data support the association of an altered oxidant-antioxidant profile in cancer patients with tumor growth and progression.

Adult↗
PubMed1996

Bronchial hyperresponsiveness as a predictor of wheezing in a follow-up study of healthy men.

We assessed the relationship between bronchial hyperresponsiveness (BHR) and the onset of wheezing 5 years later, by epidemiological analysis of 194 working men without asthma or wheezing at the first examination. In 1985/ 1986 and 1990/1991, subjects answered a British Medical Research Council questionnaire and performed lung function measurements and methacholine challenge tests (total dose 6 mg). BHR was measured in three ways: (1) FEV1 fall > or = 20% (PD20+); (2) the two-point response slope expressed as percentage decline of FEV1/dose, and (3) a four-parameter model: FEV1 at dose (d)/ prechallenge FEV1 = ONE-k(d-delta)+a, where 'k' is the slope of the relative variation of FEV1 with the dose, 'delta' the threshold dose, and 'alpha' a shape factor. In the 13 new wheezers, the mean values of the two-point slope and of k were significantly increased, and the proportion of reactors was almost threefold (the latter was not statistically significant). Among nonsmokers, delta was significantly lower in new wheezers than in the others, whereas the slope and k had similar mean values. Among smokers, new wheezers had increased mean values for the slope and k, and an increased proportion of reactors, whereas delta was not decreased. Thus, BHR was a significant predictor of wheezing, independent of the method of analysis. Moreover, the model distinguished between two components of bronchial response: wheezing was predicted by sensitivity (delta) in nonsmokers, and by reactivity (k) in smokers.

Adult↗
PubMed1995

Peak expiratory flow rate variability in population surveys. Does the number of assessments matter?

We investigated the effect of reducing the number of daily peak expiratory flow (PEF) measurements on (1) the amplitude of PEF variability and (2) the relationships of this amplitude to bronchial reactivity to methacholine. One hundred seventeen workers (mean age = 38.7 years +/- 9.5; men = 86.3%) recorded their highest of three PEF measurements, every 3 waking hours, ie, 5 times a day, for 7 days, each using a newly purchased peak flowmeter (Vitalograph), and underwent methacholine challenge tests. The variability of PEF of each subject was expressed using the three sets of indices: amp%mean, ie, highest of the daily measurements considered minus the lowest/mean x 100, averaged over 6 days from the second to the seventh, amp%highest (same as amp%mean, but with the highest daily measurements as denominators) and SD%mean (calculated initially as single measures using the data of the 6 days considered, with standard deviation (SD) of each subject's PEF measurements). For each set, we used the indices constructed with the five daily measurements of each day (gold standard), with the first, third, fourth, and fifth, the first, third, and fourth, the first and third, and the first and fourth. The PEF variability was significantly reduced when reducing the number of daily measurements, only when the amp%mean and the amp%highest sets were used. No decrease was observed with the SD%mean set of indices, and SD%mean constructed with the first, third, fourth, and fifth daily measurement was satisfactory. Whatever the sort of index used, three daily measurements were sufficient to identify the group of subjects with excessive variability in relation to methacholine reactivity.

Adult↗
PubMed1994

Trends in asthma-induced mortality in France from 1970-90.

OBJECTIVE: The object of this research was to study the evolution of asthma-induced mortality in France from 1970-90 in the whole population and by age group. DESIGN: Data from the French National Institute of Health and Medical Research (INSERM) and the population groups established by the French National Institute of Statistics and Economic Studies (INSEE) were used. The study was carried out on age-specific, crude and age-adjusted rates. RESULTS: In the general population, a drop in the age-adjusted rates can be observed from 1970-80 in men and only until 1975 in women, followed by an increase until 1986 and then another drop. The rates among women have become closer to those in men. Among those aged 5-34, a clear increase is apparent in the age-adjusted rates for both sexes, in particular in the groups aged 15-24 and 25-34. In the older age groups, this increase involves only men aged 55-64 and women from 65 years onward. CONCLUSION: It is highly unlikely that the variations observed can be explained by biases, and the increase seems therefore to be real, particularly in women and in those aged 5-34.

Adolescent↗
PubMed1992

Aging and cancer: plasma antioxidants and lipid peroxidation in young and aged breast cancer patients.

The relationship between aging and cancer is complex because the intrication takes place at the cell, the organism and the environment levels. On the other hand, carcinogenesis is a multi-step process, and different mechanisms may be involved in each step. For example, oxidants and antioxidants may play a different role depending upon the phase considered. Tumors in older patients are generally described as slow growing. The difference in tumor aggressiveness between young and older patients is especially obvious in breast cancer patients. The age specificity of some breast risk factors suggests that breast cancer which has been diagnosed in an aged woman was induced late in her life. We address the question whether the characteristics of a senescent organism with regards to oxidant-antioxidant status could be causally related to the slow evolution of tumors in old patients.

Adenocarcinoma↗
PubMedDate not supplied

Short-term effects of low-level winter pollution on respiratory health of asthmatic adults.

We studied the short-term effects of Paris winter air pollution (i.e., sulfur dioxide, Black Smoke, suspended particulates with an aerodynamic diameter close to 10 microm, and nitrogen dioxide) in 40 nonsmoking mild to moderate asthmatics (52% male; mean age = 46 y; 90% treated with inhaled steroids). During a 6-mo period, subjects recorded asthma symptoms and three daily peak expiratory flow measurements. Statistical analysis (i.e., generalized estimating equation models that accounted for autocorrelation of responses, weather data, and time trends) revealed consistent and significant associations between the pollutants and asthma attacks and symptoms in the entire study group, especially in the subgroup of individuals who took inhaled beta2 agonists as needed. Pollutants correlated negatively with morning peak expiratory flow in the subgroup that took inhaled beta2 agonists as needed, and they correlated positively with daily variability in asthmatics who received regularly scheduled inhaled beta2 agonists. The effects lingered several days after exposure occurred. Low-level pollution has consistent measurable effects on nonsmoking adults who have well-treated mild or moderate asthma.

Adolescent↗