Prevalence of asthma in adolescents in various parts of France and its relationship to respiratory allergic manifestations.

Six studies have been carried out in France and French Polynesia to investigate the prevalence of asthma in adolescents attending secondary school and in Paris university students (68,179 subjects overall). All the studies used the same questionnaire, self-administered in the classroom, and interviews administered to students during the university's preventive medicine examination. An epidemiologic definition of asthma was considered an affirmative answer to the question, "Have you ever had attacks of asthma?" The prevalence of asthma ranged from 4 to 12 percent, most often higher in boys with a tendency to increase with age. The relationship between asthma and other allergic respiratory conditions was studied. Some recommendations are made here to improve the validity of data and to increase knowledge about the etiology of asthma.

Spirometry and maximal expiratory flow-volume curve reference standards for Polynesian, European, and Chinese teenagers.

Lung function was compared and reference standards were determined in 1,007 Polynesian, European, and Chinese teenagers attending school in Tahiti (517 boys, 490 girls; mean age, 14.4 years). Spirometric study results and maximal expiratory flow-volume curves were measured using techniques recommended by the American Thoracic Society. Age, standing height, and weight were chosen as the independent variables for males, and age and standing height for females. Regression equations constructed with logarithmically transformed dependent variables provided accurate predictions. We observed significant racial differences: in the Europeans, forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were higher than the mean values predicted for the whole study population, while forced expiratory flow during the middle half of the FVC (FEF25-75%) and maximal expiratory flows after 25, 50, and 75 percent of FVC had been exhaled (V max 25, 50, and 75, respectively) were about equal to the mean values; in the Polynesians, volumes and flows were mostly lower than the mean; in the Chinese, FVC in boys and girls, and FEV1 in girls only, were lower, while the other flows were higher. The FEV1/FVC, FEF25-75%/FVC, Vmax25/FVC, Vmax50/FVC, and Vmax75/FVC were significantly higher than the mean in the Chinese boys and girls and often lower in the Europeans.

Frequency and correlates of the saw-tooth pattern of flow-volume curves in an epidemiological survey.

The object of this report was to assess the possibility of identifying saw-tooth patterns on flow-volume curves in men aged 28 to 58 years. We studied the frequency of these patterns and their relationships with two indirect signs of UAO increase in FEV1/PEF and FEF50%/FIF50% ratios--as well as with clinical and functional data. Twenty-six of the 360 subjects surveyed, ie, 7.2 percent, had flow oscillations in the inspiratory and/or expiratory part of flow-volume curves, corresponding to the definition of the saw-tooth pattern. We observed significant relationships between the saw-tooth pattern and the mean FEV1/PEF ratio. In 97 subjects, the proportion of those with saw-tooth patterns was 13.4 percent, and the mean FEF50%/FIF50% ratio was 1.53 in those with the pattern vs 1.07 in those without it. These results show that the saw-tooth pattern was not rare in these men.

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.

Respiratory history during infancy and childhood, and respiratory conditions in adulthood.

The aim of this paper was to study respiratory disorders in infancy and childhood as a risk factor for respiratory conditions in adulthood. During the first part of the survey 15,247 adolescents in the Bordeaux area (average age: 16.5 years, boys = 46.6%) filled in a self-administered questionnaire concerning their respiratory history during infancy and childhood, their present symptoms and their smoking habits. Each subject with chronic cough (n = 538) was then matched with two controls (n = 1094) and the parents of these subjects and of their controls were sent a complementary questionnaire. During the second part, 1807 adults (average age: 39.3 years; men = 49.7%) working at Bordeaux University filled in a self-administered questionnaire about their present respiratory symptoms, smoking habits and respiratory symptoms during adolescence. Spirometry was performed in 172 adolescents and 1665 adults. The results of the first part showed a very significant relationship in adolescents between respiratory history during infancy and childhood and current chronic cough even in non-smokers, non-wheezers and non-asthmatics. The second part showed a very significant relationship in adults between respiratory symptoms during adolescence and present respiratory symptoms on the one hand, and a lower pulmonary function on the other, taking wheezing, smoking and asthma into account. In common with many similar studies, we conclude that respiratory disorders in young children may predispose to later disease, and that consequently it might be important to determine appropriate measures to prevent respiratory illness in childhood.

Common cold with cough on the day of examination: a factor that should be taken into account in epidemiological studies on pulmonary function.

Epidemiologists using pulmonary function tests agree that a number of factors have to be taken into account. In a study carried out among 912 men aged 22 to 54 we found that those having a common cold and cough on the day of examination had lower pulmonary function values. So we suggest that these symptoms should also be considered as a potential confounding factor.

Prevalence of respiratory symptoms in Parisian teenagers according to smoking habits.

The relationship between respiratory symptoms and smoking habits, according to sex, was studied in 2266 teenagers attending secondary school in Paris. Among smokers, the prevalence of usual cough or phlegm, or both, was higher in girls than in boys, whereas such was not the case among non-smokers. That prevalence, as well as the proportion of people with wheezing, were more closely associated with the total number of cigarettes ever smoked by girls than by boys. Moreover, there was a weak but significant association between the total number of cigarettes smoked and respiratory function--FEV1/Ht3 in girls only.

Prevalence of asthma among teenagers attending school in Tahiti.

The prevalence of asthma was studied in 6731 adolescents (average age 13.5 years, 48.6% boys) attending school in three towns of the isle of Tahiti, according to the ethnic origin of both parents. The pupils completed a self-administered questionnaire in class; 14.3% gave an affirmative answer to the question "Have you ever had attacks of asthma?" (cumulative prevalence). That prevalence was 11.4% in the Europeans, 13.7% in the Chinese, 13.8% in the Polynesians, 15.3% in those whose parents were "halves" (half-bred from Polynesians and Europeans), and 16.0% in the miscellaneous group (= other origins) (P less than 0.02). Asthma was significantly more frequent in boys only among the Europeans and those with one European parent. The results of this study confirm the high prevalence of asthma in French Polynesia found in a previous study. They give no evidence of a racial difference in prevalence but suggest an influence of environment.

Prevalence of asthma and asthma-like symptoms in three French cities.

BACKGROUND: This study is part of the European Community Respiratory Health Survey (ECRHS), which uses a common methodology in different areas throughout the world. This paper describes the prevalences of reported asthma, asthma-like symptoms and nasal allergies, their relationships to age group and sex, and the relationships of asthma-like symptoms to current asthma, in the general population aged 20-44 years of three French urban areas. METHODS: The study population of 2804 subjects in Grenoble, 3774 in Montpellier and 3152 in Paris (18th district), randomly selected from electoral rolls, answered a postal questionnaire (stage I of ECRHS). The response rates were 77.8%, 68.6% and 74.4%, respectively. RESULTS: The prevalences were approximately 14% for wheezing, 16% for chest tightness and 4.5% for nocturnal shortness of breath in the three areas. Asthma attacks in the last 12 months were reported by 2.7% of subjects in Grenoble, 3.5% of subjects in Montpellier and 4.0% of subjects in Paris (P = 0.02). For nasal allergies, the prevalences were 28.0%, 34.3% and 30.8%, respectively (P < 0.001). Asthma was inversely correlated to age (higher prevalence in the youngest) but was not related to sex. Neither age distribution nor sex ratio explained the differences between areas. Among the asthma-like symptoms, wheezing and nocturnal shortness of breath correlated strongly with asthma, chest tightness correlated moderately and nocturnal coughing correlated poorly. CONCLUSION: The prevalences observed were higher than expected from previous comparable French studies in young adults. These results are consistent with the hypothesis of a recent increase of asthma and allergies.

[Factors related to a population's behaviour towards x-ray screening of tuberculosis (author's transl)]. / Recherche des facteurs liés au comportement d'une population à l'égard du radiodépistage systématique de la tuberculose.

A study on the behaviour of a population towards a preventive measure (X-ray screening of tuberculosis) was carried out in 6,176 adults (average age 55), offered screening by the Mobile X-ray Screening Department of "D.D.A.S.S.", from February to June 1979, 68.6 per cent of them completed and returned the self-administered postal questionnaire. The following factors were related to people's behaviour: age, occupation, educational level, the fact of being invited for the second or third time and of not being vaccinated by B.C.G. According to the results of this survey no personal motivation related to the knowledge and the fear of the disease seems to guide people in their response to the measure offered.

Misuse of pressurized metered dose inhalers by asthmatic patients treated in French private practice.

Although metered dose inhalers (MDIs) are widely used to treat asthma, clinical studies suggest that misuse is frequent. We studied the frequency of, and factors related to, misuse of MDIs in asthmatic patients of French private practice. 264 chest specialists or general practitioners completed questionnaires including characteristics of patients and asthma, technique in using inhalers and previous instruction, for three consecutive asthmatics aged > 6 years and currently using MDIs: 668 adults (mean age 47.8 years +/- 18.5, 51.8% males) and 100 children (mean age 11.5 years +/- 2.1, 72.0% males) were included. Adequate technique (deep inspiration synchronized with inhaler activation, followed by holding breath for 5 seconds) was used by 33.2% of adults and 26.0% of children; optimal technique (same, plus shaking the inhaler before use and activating it only once) was used by 22.1% of adults and 20.0% of children. The main factor related to misuse of MDIs was absence of previous instruction. However only 26.5% of instructed adults and 22.1% of instructed children used the optimal technique. Misuse of MDIs is a public health problem and instruction is unlikely to solve it. The use of different types of devices, like dry powder breath-actuated inhalers should be encouraged.

[Evolution of knowledge on the treatment of tuberculosis and therapy prescribed in all new cases of pulmonary tuberculosis in a French community since 1970]. / Evolution des connaissances sur le traitement de la tuberculose et prescriptions thérapeutiques appliquées à l'ensemble des nouveaux cas de tuberculose pulmonaire d'un département français depuis 1970.

The many papers about the treatment of tuberculosis published during the last fifteen years show the different stages of the evolution of knowledge in this field. The Register of tubercular patients, steadily brought up to date in the French "département" Bas-Rhin, gives interesting information concerning the evolution of treatment in routine. The nature of chemotherapy shows that the newly acquired knowledge is rapidly applied, whereas the average duration of treatment is regularly shortened but is still longer than the duration recommended by researchers. A greater discrepancy appears in hospitalisation: although the efficacy of domiciliary treatment has been known and proved since the early sixties, the proportion of patients having an entirely domiciliary treatment is still low, and in 1978 over 3 patients out of 4 were hospitalized for 4.4 months on average.

[Smoking in adolescents in Guadeloupe]. / Tabagisme chez les adolescents en Guadeloupe.

A study was made of the smoking habits of 10,349 teenagers attending secondary school in Grande-Terre, Lamentin and Marie-Galante in Guadeloupe (41.4% were male; mean age 16.4 +/- 1.8). The study was made using a self administered questionnaire which also included questions on respiratory symptoms in teenagers and the smoking habits of their parents. The proportion of regular smokers (greater than one cigarette per day) was 9.2% in boys and 5.6% in girls: the boys were smoking on average 7.3 cigarettes a day, the girls 5.9. The proportion of smokers increased with age, being the highest in the children of managerial and commercial classes or skilled artisans, and was strongly linked to the smoking habits of the parents. Respiratory symptoms were more common in teenagers who smoked.

[Asthma in private pneumology practice]. / Asthme en pneumologie libérale.

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.

[Construction and validation of a respiratory epidemiological questionnaire]. / Construction et validation d'un questionnaire en épidémiologie respiratoire.

This paper illustrates the principles of construction and validation of an epidemiological questionnaire by using various aspects of the questionnaire prepared for the Epidemiological Study of the Genetic and Environmental Factors in Asthma, Bronchial Hyper-responsiveness and Atopy (EGEA). Standardised international questionnaires (for adults and children) were adapted and augmented for the requirements of the study. New areas in relation to international epidemiological studies are described (detailed descriptions of asthma and allergic rhinitis, trigger factors exposure tovarious environmental factors and family history). Various aspects of validation are discussed: the acceptibility by the study of missing data in the description of asthmatic symptoms, the construct validity for a score for allergic rhinitis, the reliability of a new self-administered questionnaire for perceived hyper responsiveness to various stimuli and the validity of reported family history using information obtained from family members. Some of these elements could be used in the context of other clinical and epidemiological studies. The complete questionnaire, together with the source of the questions, instructions for interviewers and the method of coding are presented in an appendix available on the internet (http://www.splf.org/bbo/revues-articles/RMR/depotElectronique/2001-110_Kauffmann/Kauffmann2002.htm) which supplements the printed paper.

[Antitubercular therapeutic regimens routinely prescribed in Bas-Rhin and results of treatment]. / Régimes thérapeutiques antituberculeux prescrits en routine dans le Bas-Rhin et résultats du traitement.

The overall plans and therapeutic regimens prescribed for new cases of pulmonary tuberculosis notified in the Bas-Rhin in 1979 to 1980 (372 Subjects) were studied, as were relapses occurring over a three year period from the date of notification. As in the preceding analysis of cases between 1970/78, the proportion of patients treated exclusively at home was low (22.8%) and the duration of stay in a Sanatorium was lengthy (mean 86.6 days for cases without bacteriological confirmation and 142.3 days for bacteriologically positive cases). The mean duration of chemotherapy was 12.5 months (+/- 3.7). The therapeutic regimens prescribed showed a significant variability: if 80.6% of patients received, at one time or another, the combination of Isoniazid (H), Rifampicin (R) and Ethambutol (E), only 33.9% of the adults treated received the HRE/HR regimen, for periods of variable duration. Four relapses were seen during the fixed follow-up period.

[Development over 3 years of asthma recently diagnosed in a cohort of children (ASMA study). Factors related to improvement in clinical status]. / Evolution sur 3 ans de l'asthme récemment diagnostiqué dans une cohorte d'enfants (étude ASMA). Facteurs liés à l'amélioration de l'état clinique.

OBJECTIVE: The objective of the ASMA study was to describe the evolution of light to moderate asthma, newly or recently (12 Pounds months) diagnosed in private pneumology centers, and to search for the predictive factors. METHODS: In 1995, 251 private pneumologists, throughout Metropolitan France, recruited 396 asthmatic children, 6 to 12 years old (64% boys). The 334 patients eligible for the study were examined every 4 months during 3 years (a mean of 6 controls were conducted out of the expected 9). The data were collected on standardized questionnaires completed by the physicians and notebooks filled-in by the patients the week before each control. This questionnaire comprised two asthma 'control' criteria: "control" of the clinical state, defined as asthma attacks < 1 per week AND nocturnal awakening < 1 per week AND absence of asthma symptoms between attacks on every control visit; "control" of the need for b2 mimetics on request, defined as the non-use throughout the week preceding the control visit. RESULTS: The global clinical state of the cohort rapidly improved once care was initiated: the proportion of children exhibiting at least one attack of asthma per week rapidly dropped to 43% on inclusion and to 13% on the first control visit (4 months), 10% on the second control visit, and then fluctuated at around 8% up until the last control visit. A similar evolution was noted regarding nocturnal asthma attacks. The proportion of patients with prescriptions for inhaled corticosteroids and long-lasting b2-mimetics increased over the three years of follow-up. Analysis of the factors related to the individual 'control' of the clinical state showed a negative effect in family histories of asthma (father) and the presence of smokers in the home, but above all a positive effect of compliance to treatment and particularly its understanding (OR = 2.5; p = 0.03) and respect of the doses (OR = 2.7; p < 0.01). The positive effect of compliance was confirmed by analysis of the factors related to the use of b2 mimetics on request. CONCLUSION: Smoking should be avoided in the home. Compliance to treatment could be improved by making sure that the patients and their parents fully understand the disease and its treatment, and by persuading them to strictly follow the treatments prescribed.

[Respiratory pathology in occupational medicine: evaluation of 3 methods of data collection and research on risk factors]. / Pathologie respiratoire en médecine du travail: évaluation de trois modes de recueil des données et recherche des facteurs de risque.

Three methods of gathering data of respiratory symptoms (using a self questionnaire, a detailed interview and a shortened interview) were compared in 4.206 construction workers in different branches of their profession. There was non significant difference between the replies given, in either sex, to the self questionnaire and those given in the detailed interview by employees of the research bureau. The comparison between the long and the short interview, carried out on the painters, plumbers, carpenters and brick-layers did not show any difference for those questions asked in the same manner in the two documents. On the other hand the question relating to intrathoracic wheezing, which was more condensed in the shortened interview, did not have the same degree of affirmative replies. The replies concerning cough and expectoration obtained by the two methods enabled a comparison to be made between prevalance of chronic bronchitis in the different occupations. This pathology was most frequently seen amongst bricklayers and painters. Other factors (nationality, age, smoking habits) were also linked to chronic bronchitis. Taking all these factors into account has not weakened the link between chronic bronchitis and occupation.

[Biological and clinical prevalence of pollinosis caused by ragweeds of the upper valley of the Rhône corridor]. / Prévalence biologique et clinique de la pollinose due aux ambroisies dans la vallée supérieure du couloir rhodanien.

An epidemiological study of ragweed allergy was conducted on 646 employees belonging to 6 factories located in the Rhone valley south of the city of Lyon. Information on seasonal evocative clinical symptoms was obtained through a self-administered questionnaire. Biological prevalence was assessed by measuring anti-ragweed IgE specific antibodies. Measurements were performed by immunoenzymatic assay (W1 Phadezym RAST from Pharmacia). 34 (5,4%) subjects had evocative symptoms whereas 37 (5,9%) had increased specific IgE. Persons with the highest IgE levels were symptomatic. Concordance between symptoms and biology was 35% (12/34). Results indicate that sensitization level varies according to the location of the factory and people's residence, the risk to become allergic being of 10% in the most exposed population. This data emphasize the need to promote anti-ragweed eradication policy.