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R Liard

Publications and source records attributed to R Liard.

At least 37 records · Page 2Linked to original sources
PubMed1995

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.

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↗
PubMed1995

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.

Adolescent↗
PubMed1994

HIV infection and tuberculosis: an epidemiological study from a French register.

SETTING: The possible impact of the human immunodeficiency virus (HIV) infection on the epidemiology of tuberculosis has never been studied in a general French population. OBJECTIVE: To describe the evolution of tuberculosis incidence from 1983 to 1991 in a French district (Rhône) and to assess its relationships to HIV-related factors, and to determine the prevalence of HIV infection among adult tuberculosis patients registered from 1989 to 1991. DESIGN: Information on sex, age, country of birth and the history and site of tuberculosis was derived from notification forms, and information on HIV testing was collected especially for this study. RESULTS: During these nine years, 2916 tuberculosis cases were registered. The incidence increased in 1991 after a slow decline in previous years. An analysis of the evolution in the distribution of cases did not suggest any effect of HIV infection on the epidemiology of tuberculosis, with the exception of an increase in the proportion of patients originating from the Antilles and sub-Saharan Africa. The conservative estimate of prevalence of HIV infection was 9.8% in young adult patients. CONCLUSION: The overlap between the population with HIV infection and that with tuberculosis seems to be small and restricted to particularly vulnerable sub-groups of the population of this region.

AIDS-Related Opportunistic Infections↗
PubMed1992

Peak expiratory flow variability and bronchial responsiveness to methacholine. An epidemiologic study in 117 workers.

We studied the relationships between peak expiratory flow (PEF) variability and bronchial responsiveness to methacholine in 117 workers attending the annual compulsory examination (mean age, 38.7 yr +/- 9.5; men, 86.3%). Subjects recorded their highest PEF out of three, every 3 waking hours (i.e., five times a day) for 7 days, each using a newly purchased Vitalograph peak flow meter, and underwent methacholine challenge tests with a maximal cumulative dose of 1,200 micrograms. Those with a FEV1 fall of 15% or more were considered as reactors. The variability of PEF was expressed as the amplitude percent mean, calculated from daily amplitude (highest-lowest reading/mean reading of the day x 100), averaged over 6 days, from the second to the seventh. This index had a continuous distribution, skewed towards the greatest amplitudes, and correlated negatively with FEV1 (r = -0.25, p = 0.01). Subjects with asthma (n = 8) had greater variations. In the 109 nonasthmatics, greater variability was observed in subjects with wheeze apart from colds, breathlessness, or hay fever; the average amplitude was greater in reactors than in nonreactors to methacholine (16.9% versus 9.3%, p less than 0.001). The subjects with excessive PEF variability were all methacholine reactors, but they were only a subgroup of the reactors. These results provide evidence that excessive PEF variability is an indicator of bronchial hyperresponsiveness to methacholine in a population sample.

Adult↗
PubMed1992

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.

Adult↗
PubMed1992

[Biological and clinical prevalence of pollinosis caused by ragweeds of the upper valley of the Rhône corridor].

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.

Adult↗
PubMed1990

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.

Adolescent↗
PubMed1989

[Smoking in adolescents in 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.

Adolescent↗
PubMed1988

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.

Adolescent↗
PubMed1988

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.

Adolescent↗
PubMed1987

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.

Adolescent↗
PubMed1986

[Antitubercular therapeutic regimens routinely prescribed in Bas-Rhin and results of treatment].

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.

Adolescent↗
PubMed1985

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.

Adult↗