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M Korobaeff

Publications and source records attributed to M Korobaeff.

At least 19 recordsLinked to original sources
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

Relationship of upper airways disorders to FEV1 and bronchial hyperresponsiveness in an epidemiological study.

Associations of upper airways disorders (UAD) with forced expiratory volume in one second (FEV1) and bronchial methacholine response were studied, taking smoking habits into account. We used epidemiological data drawn from a population of 324 men, aged 27-58 yrs. Lower FEV1 level was related to hay fever (p = 0.01), usual (p = 0.01) and chronic (p = 0.02) rhinitis and common cold on the day of examination (p = 0.04). Allowance for the major potential confounding factor, tobacco smoking, showed similar results. Bronchial methacholine response was heightened in men reporting hay fever compared to those without (p = 0.01) but also in men reporting chronic rhinitis (p = 0.06), a group which did not exhibit skin prick test positivity more often than other subjects. Exclusion of asthmatics and taking into account smoking and skin prick test positivity yielded mostly similar results. Our data support the hypothesis of an association between lung impairment, as assessed by lower FEV1 and bronchial hyperresponsiveness to methacholine, and different types of UAD, allergic or not.

Adult↗
PubMed1991

Blood eosinophilia and FEV1. Cross-sectional and longitudinal analyses.

A previous cross-sectional analysis of 1980 data from a population of working men in the Paris area has shown a significant relationship of blood eosinophilia to a reduced FEV1 among nonsmokers, remaining after excluding men with a history of asthma. In the present report, we reexamine this relationship, after taking into account asthma, bronchial hyperresponsiveness, and positive skin prick tests, using data collected in 1985 in a subsample of 363 men from the initial population. Blood eosinophilia, defined by 5% or more eosinophils or by 250 or more eosinophils per cubic millimeter appeared to be associated with a lower FEV1, primarily in nonsmokers. A difference of approximately 0.40 L was observed in never-smokers with eosinophilia (greater than or equal to 5% of eosinophils) compared with those without. This association persisted after exclusion of subjects with atopy, asthma, and bronchial hyperresponsiveness. Longitudinally, no significant association was observed between 1980 eosinophilia and the annual FEV1 decline between 1980 and 1985, even in nonsmokers. The results of our cross-sectional analyses suggest that asthma or asthma-like disorder does not explain the association between eosinophilia and FEV1. The role of eosinophil in respiratory disorders may go beyond its intervention in allergy. Further longitudinal studies are needed to better understand discrepancies between cross-sectional and longitudinal data and whether eosinophilia is a risk factor for chronic air-flow limitation.

Adult↗
PubMed1988

Relation of perceived nasal and bronchial hyperresponsiveness to FEV1, basophil counts, and methacholine response.

Perceived nasal and bronchial hyperresponsiveness to tobacco smoke and cold air were assessed in 912 working men in the Paris area. Baseline lung function measurements and peripheral leucocyte counts with standard differential counts were performed. At least one perceived nasal or bronchial hyperresponsiveness symptom was reported by 15.7%. Current smoking was significantly less frequent among those with cough induced by tobacco smoke. Rhinitis induced by cold air was associated with lower FEV1 (p less than 0.01) and the association remained after adjustment for smoking, asthma, and wheezing (p = 0.06). Symptoms induced by cold air were related to circulating basophils. Neither perceived nasal nor perceived bronchial hyperresponsiveness was significantly related to the airway response to methacholine in a sample of the group (n = 324) surveyed again five years later. The result suggest that the symptom of rhinitis provoked by cold air is a possible "new" risk factor or marker for chronic airflow limitation.

Adult↗
PubMed1987

Variation of lung function during the workshift among cotton and jute workers.

Cotton and jute dust exposure is known to induce reversible airway obstruction. We compared 50 exposed workers to 99 non exposed workers for the prevalence of respiratory symptoms and ventilatory impairment, and for variations in pulmonary function after five working days and after inhalation of salbutamol. The prevalence of respiratory symptoms was not significantly different between the two groups. Pulmonary function was not different on Monday morning, however, significant differences were observed on Friday afternoon. The exposed workers had a lower flow rate at 75% of exhaled forced vital capacity than controls (P less than 0.01). Salbutamol induced greater bronchodilatation in the exposed group. Comparison with a control group is necessary to take into account the change in pulmonary function. Repeated tests, combined with pharmacological tests, are able to differentiate the lung function pattern of exposed and non exposed workers.

Adult↗
PubMed1986

Eosinophils, smoking, and lung function. An epidemiologic survey among 912 working men.

The relationship of eosinophilia with smoking habits and with baseline lung function measurements has been studied in a working population of 912 men in the Paris area. Absolute numbers of eosinophils were related significantly to a history of asthma and eczema in childhood as well as to current tobacco consumption, whereas the percentage of eosinophils was related only to the occurrence of asthma and eczema. Forced expiratory volume in one second adjusted for smoking was significantly related to asthma, the presence of a common cold on the day of examination among those with a history of wheezing, and the percentage of eosinophils. The association between FEV and eosinophils was restricted to never smokers. Among never smokers without a history of asthma, eczema, wheezing, or a common cold on the day of examination, eosinophil percentages and counts were significantly associated with the level of FEV; eosinophil percentages explained 4.4% of the variance of FEV. These results suggest that eosinophilia might be a risk factor for chronic air-flow limitation among adult nonsmokers.

Adult↗
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↗
PubMed1978

[Effect of a histamine aerosol in 20 subjects with histamine hyperreactivity. Application to a study of the protective properties of pipoxizine].

The authors made a study of the antihistaminic properties of Pipoxizine in 20 subjects with proven histaminic hyperreactivity. The design of the trial consisted in comparing the changes of VC, FEC1, expiratory airway resistance and V50 produced by a histamine aerosol given before and after administration of Pipoxizine. Pipoxizine was given by mouth to 10 patients and intravenously to the other 10 of the group. The statistical analysis of the results demonstrated an antagonist effect of Pipoxizine on the histamine induced bronchoconstriction. The data of this trial are confirmative of the results of other experimenters. It seems therefore reasonable to take into consideration the use of Pipoxizine in the preventive treatment of the paroxystic attacks of the asthmatic disease.

Aerosols↗
PubMed1977

[Small airway function tests; techniques of measurements. Review of the literature].

It is usually agreed that obstructive lesions in small airways are the first abnormalities in patients with chronic bronchitis. Consequently, there is now a great interest in the early detection of airways obstruction. Three techniques are described: frequency dependence of compliance, flow-volume curve and closing-volume. The results obtained in healthy subjects and in patients with obstructed airways are discussed.

Airway Obstruction↗
PubMed1975

[Measurement of the oxygen affinity of hemoglobin. Application to patients with angina pectoris with normal coronography. Study of 10 cases].

A study of 2-3 D.P.C. (diphosphoglycerate) and of P50 (PO2 of half-saturation of blood at pH 7.40, PCO2 40 torr and temperature 37 degrees C) was carried out in ten subjects: eight women and two men suffering from angina pectoris with no evidence of obstruction on their coronary arteriograms. The study was made with the subjects at rest, in the absence of any acute coronary episode. The results show that these patients have a normal affinity of haemoglobin for oxygen: the 2-3 D.P.G. was 13.05 +/- 2.2 muM.g-1 Hb; P50 was 26.7 +/- 1.3 torr; Hill's "n" was 2.65 +/- 0.29. Deviation to the right of the oxyhaemoglobin curve may be seen, after effort or during a provoked attack, but this movement to the right seems to be the result rather than the cause of the myocardial ischaemia.

Adult↗
PubMedDate not supplied

[Value and reproducibility of TLCO, TMCO and Vc in healthy subjects (author's transl)].

Transfer factor (TLCO) and its components (TMCO and Vc) have been measured in 47 healthy subjects. The regressions with respect to age and body surface were close to those found in the literature. The reproducibility of these indices has been investigated in a sub-group of 5 subjects, examined at two days intervals, for 24 to 42 days. For TLCO measured with a 16% O2 mixture, the reproducibility was good (coefficient of variation of 5%). For Vc and TMCO, the dispersion was more important and varied among the subjects. The lack of reproducibility appeared to be due, among other factors, to reading errors on the variables, and more frequently FACO. Four among these 5 subjects were asked to keep alveolar pressure close to atmospheric during the apnea; the coefficient of variation decreased from 23.5 to 7.5% for Vc and from 25.9 to 12.4% for TMCO.

Adolescent↗
PubMedDate not supplied

Analysis of the methacholine dose-response curve: usefulness of a simplified log-logistic model in epidemiological studies.

The object of the study was to find a model to summarize all the information from dose-response curves, by determining the coefficients to be used to compare groups of subjects. Three coefficients were calculated from the following model: F(d)/F(o) = ONE - k(d-delta)alpha+, where F(d)/F(o) was the ratio between FEV1 at dose (d) of methacholine and prechallenge FEV1, 'k' the slope of the relative variation of FEV1 with the dose, 'delta' the threshold dose and 'alpha' a shape factor. The model was applied to the study of hyperresponsiveness in a population of 317 men. The results illustrated the interest of this model which was applicable to 91% of the population and permitted fine discrimination of the groups studied.

Adult↗
PubMedDate not supplied

[Can an improvement in pulmonary function be demonstrated in children under 10 years sent to winter sport classes?].

The purpose of this research was to appreciate the benefit of a Winter sport class for young children. The study was carried out, in the Northern suburb of Paris, among girls and boys, aged 8.4 on average. Among them, 91 went to the mountains and 65 (controls) stayed in town. A spirometry and a flow-volume curve were measured: before starting, on coming back home and 2 years later. The parents filled in questionnaires about children's respiratory symptoms and history. Morphometric data were recorded. Reference values of this population were obtained by taking height into account. No difference in respiratory symptoms and history was observed between the groups at the beginning of the survey. However, the children who went to the mountains had lower age, weight and height than the others. Nevertheless, 2 years later, these children had a more important increase of F.E.F.1 and F.E.F.25-75. They had also a more important increase of their flows.

Altitude↗