Etude comparative sur les performances et l'ergonomie de nébuliseurs dans la mucoviscidose

National audienceThis study had, as its aim, to lest twelve nebulizers (6 jet, 6 ultrasonic) which are used in the treatment of cystic fibrosis. Devices were connected to a respirator in order to mimic the Ventilation of a child and of an adult suffering from cystis fibrosis. Three medications : tobramycine, colistine and amiloride were nebulised. The volume of the recommended solution varied between 1.5 and 13 ml according to the manufacturer. During a Session of ten minutes the ultrasonic nebulizer delivered an inhaled volume which was significantly greater than the jet (2.72+-0.98 ml vs 1.22+-0.59 ml, p <0.0001) for the three drugs. Regarding granulometry, the fraction of particles between 0.5 and 5 um, was higher with ultrasonic than with pneumatic nebulizer for tobramycine (67.1+-10.7 vs 55.5+-]1.5 %. p <0.001) and amiloride (66.4+-S1.2 % vs 58. l +-15%, p <0.05 %). The Variation of concentration due to nebulisation were independent of the type of apparatus but influenced by the drug since concentration was increased for tobramycine (+10.5+-18.6 %) and amiloride (+13.4+-8/9 %). In summary the effective fraction resulting from the inhalable fraction, from granulometry and from changes in concentration was significantly greater for ultrasonic than for jet nebrulizer (17.3+-6.7 % vs 9.7+-9.6 %, p <0.001). This study underlines the great variability of the performance of aerosols generators and therefore the need for an accurate evaluation of nebulizer performances in order to prescribe the best nebulizer/drug association in clinical practice.Cette étude avait pour but de tester douze appareils d'aérosols (six pneumatiques, six ultrasoniques) utilisés dans le traitement de la mucoviscidose. Les appareils étaient connectés à un respirateur afin de simuler la ventilation d'un enfant et d'un adulte atteints de mucoviscidose. Trois médicaments : tobramycine, colistine, amiloride étaient nébulisés. Les volumes de solution préconisés variaient entre 1,5 et 13 ml selon les fabricants. Au cours d'une séance de 10 min, les nébuliseurs ultrasoniques délivrent un volume inhalable significativement plus important que les pneumatiques (2.72+-0.98 ml vs l.22-t0,59 ml, p <0.0001) pour les trois médicaments. La fraction déposable, c'est-à-dire avec une granulométrie comprise entre 0,5 et 5 µm, est plus élevée avec les ultrasoniques qu'avec les pneumatiques pour la tobramycine (67.1+-10,7 % vs 55.5+-11.5 %, p <0,001) et l'amiloride (66.4+-9.2 % vs 58.1+-15 %, p <0,05 %). Les variations de concentration dues à la nébulisation sont indépendantes du type d'appareil, mais influencées par le médicament : augmentation de concentration pour la tobramycine (+!0,5+-I8,6 %) et l'amiloride (+13,4+-8,9 %). Au total, la fraction efficace qui résulte à la fois de la fraction inhalable, de sa granulométrie et des variations de concentration est significativement supérieure pour les ultrasoniques que pour les pneumatiques (17.3+-6,7 % vs 9,7+-9.6 %, p <0,001). Cette étude souligne la grande variabilité des performances des appareils d'aérosols, ainsi que la nécessite d'avoir des tests fiables avant l'utilisation en clinique afin de prescrire la meilleure combinaison appareil/médicament

Etude comparative sur les performances et l'ergonomie de nébuliseurs dans la mucoviscidose

National audienceThis study had, as its aim, to lest twelve nebulizers (6 jet, 6 ultrasonic) which are used in the treatment of cystic fibrosis. Devices were connected to a respirator in order to mimic the Ventilation of a child and of an adult suffering from cystis fibrosis. Three medications : tobramycine, colistine and amiloride were nebulised. The volume of the recommended solution varied between 1.5 and 13 ml according to the manufacturer. During a Session of ten minutes the ultrasonic nebulizer delivered an inhaled volume which was significantly greater than the jet (2.72+-0.98 ml vs 1.22+-0.59 ml, p <0.0001) for the three drugs. Regarding granulometry, the fraction of particles between 0.5 and 5 um, was higher with ultrasonic than with pneumatic nebulizer for tobramycine (67.1+-10.7 vs 55.5+-]1.5 %. p <0.001) and amiloride (66.4+-S1.2 % vs 58. l +-15%, p <0.05 %). The Variation of concentration due to nebulisation were independent of the type of apparatus but influenced by the drug since concentration was increased for tobramycine (+10.5+-18.6 %) and amiloride (+13.4+-8/9 %). In summary the effective fraction resulting from the inhalable fraction, from granulometry and from changes in concentration was significantly greater for ultrasonic than for jet nebrulizer (17.3+-6.7 % vs 9.7+-9.6 %, p <0.001). This study underlines the great variability of the performance of aerosols generators and therefore the need for an accurate evaluation of nebulizer performances in order to prescribe the best nebulizer/drug association in clinical practice.Cette étude avait pour but de tester douze appareils d'aérosols (six pneumatiques, six ultrasoniques) utilisés dans le traitement de la mucoviscidose. Les appareils étaient connectés à un respirateur afin de simuler la ventilation d'un enfant et d'un adulte atteints de mucoviscidose. Trois médicaments : tobramycine, colistine, amiloride étaient nébulisés. Les volumes de solution préconisés variaient entre 1,5 et 13 ml selon les fabricants. Au cours d'une séance de 10 min, les nébuliseurs ultrasoniques délivrent un volume inhalable significativement plus important que les pneumatiques (2.72+-0.98 ml vs l.22-t0,59 ml, p <0.0001) pour les trois médicaments. La fraction déposable, c'est-à-dire avec une granulométrie comprise entre 0,5 et 5 µm, est plus élevée avec les ultrasoniques qu'avec les pneumatiques pour la tobramycine (67.1+-10,7 % vs 55.5+-11.5 %, p <0,001) et l'amiloride (66.4+-9.2 % vs 58.1+-15 %, p <0,05 %). Les variations de concentration dues à la nébulisation sont indépendantes du type d'appareil, mais influencées par le médicament : augmentation de concentration pour la tobramycine (+!0,5+-I8,6 %) et l'amiloride (+13,4+-8,9 %). Au total, la fraction efficace qui résulte à la fois de la fraction inhalable, de sa granulométrie et des variations de concentration est significativement supérieure pour les ultrasoniques que pour les pneumatiques (17.3+-6,7 % vs 9,7+-9.6 %, p <0,001). Cette étude souligne la grande variabilité des performances des appareils d'aérosols, ainsi que la nécessite d'avoir des tests fiables avant l'utilisation en clinique afin de prescrire la meilleure combinaison appareil/médicament

[Epidemiological study of genetic and environmental factors in asthma, bronchial hyperresponsiveness and atopy. Protocol and potential selection bias].

International audienceBACKGROUND: The EGEA study combines a case-control study and a family study to assess genetic and environmental risk factors and their interactions for asthma, bronchial hyperresponsiveness and atopy. Information is scanty regarding potential selection biases, in particular regarding familial ressemblance in epidemiological surveys of this kind. METHODS: Asthmatic probands (adult and paediatric) were recruited in chest clinics of six clinical centres. Controls were mostly population-based (electoral rolls) for adults and recruited in surgery departments for children. RESULTS: The population examined includes 348 nuclear families ascertained by one asthmatic and 416 controls, totalling 1847 subjects (EGEA I) and an additional sample of 40 families ascertained by two asthmatic siblings (EGEA II). Potential biases for the various types of analyses have been studied. Quantification of the consequences of the greater participation of probands with a parental history of asthma shows it does not introduce a major bias in the estimates of familial resemblance. Cases and controls showed a good comparability regarding sex, age, area of residence and familial geographical origin, allowing proper associations studies for environmental and candidate genetic factors. CONCLUSIONS: The case-control component of the study will allow to perform studies on environmental factors and association studies for various genetic polymorphisms. Using the family base collected, segregation and genetic linkage/association analyses with DNA markers may be performed

EGEA (Epidemiological study on the Genetics and Environment of Asthma, bronchial hyperresponsiveness and atopy)-- descriptive characteristics.

International audienceThe Epidemiological study on the Genetics and Environment of Asthma (EGEA) was planned to assess genetic, environmental risk factors and their interactions for asthma and for the two related traits of bronchial hyperresponsiveness and atopy. The population examined includes 348 nuclear families ascertained by one asthmatic (213 adult and 135 paediatric probands) and 416 controls, totalling 1,847 subjects (EGEA I). Prevalences of asthma, skin prick test response, high IgE and bronchial hyperresponsiveness were for parents, siblings, and offspring of cases intermediate between cases and spouses or controls, both in adults and children, confirming the familial resemblance for asthma and related traits. With an additional sample of 40 families ascertained by two asthmatic siblings (EGEA II), a total of 119 families with two asthmatic siblings has been ascertained for a genome screening

[Epidemiological study of genetic and environmental factors in asthma, bronchial hyperresponsiveness and atopy. Protocol and potential selection bias].

International audienceBACKGROUND: The EGEA study combines a case-control study and a family study to assess genetic and environmental risk factors and their interactions for asthma, bronchial hyperresponsiveness and atopy. Information is scanty regarding potential selection biases, in particular regarding familial ressemblance in epidemiological surveys of this kind. METHODS: Asthmatic probands (adult and paediatric) were recruited in chest clinics of six clinical centres. Controls were mostly population-based (electoral rolls) for adults and recruited in surgery departments for children. RESULTS: The population examined includes 348 nuclear families ascertained by one asthmatic and 416 controls, totalling 1847 subjects (EGEA I) and an additional sample of 40 families ascertained by two asthmatic siblings (EGEA II). Potential biases for the various types of analyses have been studied. Quantification of the consequences of the greater participation of probands with a parental history of asthma shows it does not introduce a major bias in the estimates of familial resemblance. Cases and controls showed a good comparability regarding sex, age, area of residence and familial geographical origin, allowing proper associations studies for environmental and candidate genetic factors. CONCLUSIONS: The case-control component of the study will allow to perform studies on environmental factors and association studies for various genetic polymorphisms. Using the family base collected, segregation and genetic linkage/association analyses with DNA markers may be performed

[Epidemiological study on the Genetics and Environment of Asthma, bronchial hyperresponsiveness and atopy (EGEA) - First results of a multi-disciplinary study].

International audienceThe French co-operative epidemiological study EGEA realised in 1991/95 combines a case control study and a study of the families of asthmatic cases. A synthesis of the results already obtained is presented. Smoking was related to IgE, even in asthmatics and was clearly related to the clinical severity of asthma, an aspect insufficiently taken into account. The relationships of occupational exposures to asthma have been assessed using a job exposure matrix. Segregation analyses on IgE have shown, after correction for the mode of ascertainment, the existence of a dominant major gene and familial residual correlation. A systematic genome screen realised in families with 2 asthmatic siblings showed linkage of various regions in the genome implicated to asthma or related phenotypes (1p, 11p, 11q, 12q, 13q, 17q, 19q), coherent with genome screens realised in other studies. Regarding candidate genes, no association was evidenced between asthma and the AF508 mutation of the cystic fibrosis gene. The analysis is still in progress by studies on the heterogeneity of asthma with refined genetic studies and by searching to integrate results regarding environmental and genetic factors and studying their interactions

[Epidemiological study on the Genetics and Environment of Asthma, bronchial hyperresponsiveness and atopy (EGEA) - First results of a multi-disciplinary study].

International audienceThe French co-operative epidemiological study EGEA realised in 1991/95 combines a case control study and a study of the families of asthmatic cases. A synthesis of the results already obtained is presented. Smoking was related to IgE, even in asthmatics and was clearly related to the clinical severity of asthma, an aspect insufficiently taken into account. The relationships of occupational exposures to asthma have been assessed using a job exposure matrix. Segregation analyses on IgE have shown, after correction for the mode of ascertainment, the existence of a dominant major gene and familial residual correlation. A systematic genome screen realised in families with 2 asthmatic siblings showed linkage of various regions in the genome implicated to asthma or related phenotypes (1p, 11p, 11q, 12q, 13q, 17q, 19q), coherent with genome screens realised in other studies. Regarding candidate genes, no association was evidenced between asthma and the AF508 mutation of the cystic fibrosis gene. The analysis is still in progress by studies on the heterogeneity of asthma with refined genetic studies and by searching to integrate results regarding environmental and genetic factors and studying their interactions