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F Neukirch

Publications and source records attributed to F Neukirch.

At least 55 records · Page 3Linked to original sources

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↗

[Asthma: a world problem of public health].

Bronchial asthma, one of the most common illnesses in the western world, affecting between 8-10% of children and 3-5% of the adult population, is increasingly becoming a public health problem in the developing world. Its incidence continues to rise throughout the world and, indeed, it has been estimated that it has increased by approximately 50% over the last 10 years. The reasons underlying this alarming trend are probably related to the many possible interactions between allergens and pollution be they domestic (eg passive smoking) or atmospheric (most notably motor vehicle exhaust emissions). The severity of asthma is also increasing as is witnessed by the higher levels of hospitalization of sufferers and the increased death rate (approximately 2000 fatalities per year in France alone). Asthma changes the quality of life of patients whatever their age and is an important cause of school absenteeism and lost working days. The costs due to asthma, which currently represent approximately 1% of direct and indirect health care costs (7 thousand millions French francs), are also steadily mounting. These pessimistic facts and statistics have inspired the drafting of an "International Consensus" on the treatment of asthma sufferers and have caused the WHO to take a position drawing maximum public attention to this disease and measures for its control and prevention.

Adult↗

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↗

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↗

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↗

Eligibility for reperfusion therapy and outcome in elderly patients with acute myocardial infarction.

Reperfusion therapy by thrombolysis or angioplasty was considered in 260 unselected patients consecutively admitted within 6 h of the onset of Q wave myocardial infarction. Rates of reperfusion and in-hospital mortality were compared in 206 patients < 70 years and 54 patients > or = 70 years. Early reperfusion was obtained in 86.4% of the patients under 70 years and in 72.2% of those over 70 (P < 0.01). Thrombolysis was more frequently used in the younger group (66.0% vs 31.5%, P < 10(-5)), and primary angioplasty in the older (44.4% vs 29.6%, P < 0.05). Overall in-hospital mortality was higher in the older group (22.2% vs 4.4%, P < 10(-5)). After successful reperfusion, mortality was 12.8% in the patients over 70 and 3.9% in those under 70. After failed or unproven reperfusion, mortality was 46.7% in the patients over 70 and 7.1% in those under 70. Reperfusion therapy is feasible in the majority of patients over 70 years, but failure to attempt or to achieve reperfusion is associated with a poor outcome. Although not controlled, this study provides an incentive for attempting early reperfusion therapy as often as possible in the elderly with acute myocardial infarction.

Age Factors↗

[Measure of bronchial hyperreactivity in epidemiology].

First used to evaluate individuals with symptoms suggestive of asthma, the assessment of bronchial hyperresponsiveness is now commonly used in epidemiological studies, available methods being reproducible and portable. This chapter defines how to assess bronchial hyperresponsiveness in epidemiological studies, which factors need to be considered, what is the prevalence in different populations and finally what are the indications for measuring bronchial hyperresponsiveness in epidemiological studies.

Adolescent↗

Relation of serum elastin peptide concentration to age, FEV1, smoking habits, alcohol consumption, and protease inhibitor phenotype: an epidemiological study in working men.

BACKGROUND: In clinical investigations elastin peptide concentration has been proposed as one potential marker of lung elastin degradation. No epidemiological study has yet confirmed this hypothesis. METHODS: The relation of elastin peptide concentration to some factors closely related to pulmonary emphysema (age, smoking habits, FEV1 alpha protease inhibitor (PI) phenotype) and to alcohol consumption was examined in an epidemiological study of 310 working men. The elastin peptides used for obtaining antibodies and as reference in an ELISA assay were prepared from chemically hydrolysed elastin. RESULTS: The elastin peptide concentration significantly decreased with age from 2.92 (1.54) micrograms/ml among subjects younger than 30 years to 2.18 (1.14) micrograms/ml among subjects older than 50. Elastin peptide concentration did not differ with smoking habits and was clearly unrelated to FEV1. A lower elastin peptide concentration was observed in all groups of subjects with a protease inhibitor phenotype other than PI MM (PI FM, IM, MP, MS, MZ, and S phenotypes). CONCLUSIONS: The results cast doubts on the usefulness of the elastin peptide concentration as a marker of lung destruction in middle aged, predominantly healthy men. Blood elastin peptide concentration may reflect both elastin degradation and resynthesis. The results of this analysis suggest that several factors (age, alcohol consumption, non-PI MM phenotype) may be associated with decreased resynthesis of lung elastin. Further studies, conducted in various age groups and including estimates of the degree of lung destruction, are needed to unravel the mechanisms underlying lysis and resynthesis of lung elastin.

Adult↗

Different effects of nasal and bronchial glucocorticosteroid administration on bronchial hyperresponsiveness in patients with allergic rhinitis.

Disorders of the upper respiratory tract, particularly allergic rhinitis, are commonly associated with bronchial hyperresponsiveness. The latter may be due to postnasal drip or to mediator or chemotactic factors into the lower airways that either directly alter airway reactivity or cause airway inflammation. The aim of this study was to compare the effect of an identical dose of nasal or bronchial corticosteroid administration on bronchial hyperresponsiveness in patients with allergic rhinitis. Eleven patients were studied. All of them were judged atopic on the basis of positive skin tests to common allergens. During control, spirometry, flow-volume curves, and specific airway conductance (SGaw) were measured. Bronchial challenges were then performed with increasing concentrations of carbachol, and dose-response curves were constructed. The concentration of carbachol that decreased SGaw by 35% from baseline (PD35) was determined by interpolating from the dose-response curve. Control measurements were repeated at 1-wk intervals to ensure that PD35 was stable in all the patients. Then the patients received for 2 wk, in a double-blind randomized crossover fashion, a topical administration of either an aerosol of 400 micrograms of beclamethasone dipropionate (B) into the nose (100 micrograms four times per day) or into the bronchi. During each trial period, identical sprays of placebo were used, the latter being administered into the nose when B was administered into the bronchi and vice versa. Measurements were then performed after 2 wk of intranasal administration and after 2 wk of intrabronchial administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Inhalation↗

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↗

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↗

Total circulating IgE and FEV1 in adult men. An epidemiologic longitudinal study.

Epidemiologic data relating total circulating immunoglobulin E (IgE), an objective marker of allergy, to cross-sectional and longitudinal FEV1 as well as to methacholine bronchial hyperresponsiveness were obtained from 310 French adult men surveyed five years apart. Skin prick test responses to common aeroallergens, IgE level, and bronchial hyperresponsiveness were assessed at the end of the follow-up. IgE level was not associated with PD20 to methacholine. Cross-sectionally, age and height-adjusted FEV1 score was inversely related to total IgE level (regression coefficient of FEV1 score on Log[IgE] beta = -.20; p = 0.02). Stratified analysis showed that IgE level was associated with FEV1 score only in nonsmokers (beta = -0.52; p less than 0.001), an association that remained after exclusion of asthmatics. Longitudinally, five-year FEV1 decline was related to IgE in nonsmokers (regression coefficient of FEV1 decline on Log[IgE] beta = 19.9; p = 0.03) and exsmokers (beta = 18.9; p = 0.06) but not in current smokers. The relationship persisted, even if with lesser significance, among exsmokers after exclusion of asthmatics (beta = 17.2) and further exclusion of skin prick test-positive men (beta = 18.8). Whether IgE production also reflects factors other than allergy, possibly nonallergic inflammation, needs further investigations.

Adult↗

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↗

[Mortality related to asthma. Trends in France from 1970 to 1987].

An increase in mortality related to asthma has been observed in a great number of countries during the last decade. The purpose of this work is to study this evolution in France from 1970 to 1987. Numbers of deaths were obtained from INSERM, by sex and age groups and the corresponding populations from INSEE. Data were interpreted from crude rates and with the computation of age adjusted and age specific rates. In men, we observed a decrease in mortality from 1972 to 1979, then an increase from 1980 to 1987. In women, the decrease stopped as early as 1974 and we observed an increase from 1975 to 1987. On the other hand their crude and age-adjusted rates become higher than men's rates as early as 1977.

Adolescent↗

[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↗

Relationships of haptoglobin level to FEV1, wheezing, bronchial hyper-responsiveness and allergy.

The relationships of haptoglobin level to respiratory and allergic parameters have been assessed in an epidemiological study conducted in a working population surveyed twice 5 years apart. At the first survey conducted in 892 working men, haptoglobin level was significantly related to FEV1 (r = -0.18; P less than 0.001) and smoking habits. After adjustment for smoking, a history of wheezing was significantly related to lower haptoglobin level. A second survey conducted in 304 men of the original sample 5 years later confirmed that haptoglobin was related to FEV1 (r = -0.21; P less than 0.001) and that wheezing was significantly related to hypohaptoglobinaemia (lower decile; P = 0.04). Men who exhibited bronchial hyper-responsiveness to methacholine had haptoglobin levels 0.35 g/l higher than those who did not (P = 0.01). Haptoglobin level was unrelated to IgE level and skin prick tests. These results support the hypothesis of the role of inflammation in both lower lung function and bronchial hyper-responsiveness. They suggest that some heterogeneity exists within subjects with a history of wheezing.

Adult↗

Protective effect of theophylline on bronchial hyperresponsiveness in patients with allergic rhinitis.

Disorders of the upper respiratory tract, particularly allergic rhinitis are commonly associated with bronchial hyperresponsiveness. The latter may be responsible for chronic cough, a common symptom in patients with allergic rhinitis, which, as previously shown, can be the sole presenting manifestation of bronchial hyperresponsiveness. Theophylline is widely used in patients with asthma for its bronchodilator effect, whereas its action on bronchial reactivity is controversial. The aim of this study was to determine the effect of theophylline administration on bronchial hyperresponsiveness in patients with allergic rhinitis complaining of chronic cough. Fourteen patients were studied. All of them were judged atopic on the basis of positive skin tests to common allergens. During control, spirometry, flow-volume curves and specific airway conductance (SGaw) were measured. Bronchial challenges were then performed with increasing concentrations of carbachol, and dose-response curves were constructed. The concentration of carbachol, which decreased SGaw by 35% from baseline (PD35) was determined by interpolating from the dose-response curve. After control measurements patients received in a randomized, double-blind crossover fashion either theophylline 10 mg/kg/day orally or placebo for 30 days. Measurements were then redone. After a washout period of 8 days the measurements were repeated, and patients received theophylline or placebo for a second period of 30 days. Measurements were again performed at the end of this last study period. During control all patients had normal baseline lung function data and showed marked bronchial hyperresponsiveness, PD35 amounting to 26 +/- 7 micrograms of carbachol (normal value greater than 160 micrograms). No significant changes in PD35 were noted after placebo and washout when compared with control values.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

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↗