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J L Racineux

Publications and source records attributed to J L Racineux.

At least 19 recordsLinked to original sources
PubMed2001

[Obstructive sleep apnea syndrome and cardiovascular risk].

Numerous studies have shown that obstructive sleep apnea syndrome (OSAS) is associated with an increased cardiovascular morbidity and mortality. Obstructive sleep apnea syndrome and cardiovascular disorders are frequent diseases. They share several risk factors such as age, gender, obesity, smoking, and alcohol. Therefore it is difficult to demonstrate that OSAS is a cardiovascular risk factor, independent of previously known factors. Recent epidemiological studies and trials, consistent with the results of previous studies, have demonstrated a strong association between OSAS and systemic hypertension. They also suggest that there is a possible cause-effect relation between OSAS and coronary artery disease or cardiac arrhythmias. Studies demonstrating that early recognition and treatment of OSAS may be effective in reducing these cardiovascular complications are still needed.

Arrhythmias, Cardiac↗
PubMed1999

[Profiles of 939 patients with obstructive sleep apnea syndrome treated with continuous positive pressure].

The aim of this study was to analyze the characteristics of patients on long-term continuous positive pressure therapy for obstructive sleep apnea in order to determine the efficacy, observance, tolerance, degree of patient satisfaction and patient quality of life using the Nottingham scale. A questionnaire was sent to 939 patients treated for at least six months in 11 centers. Factorial analysis of multiple correspondences and two classification analyses were used to establish patient profiles. Factorial analysis evidenced a relationship between patient satisfaction, reduced symptoms, observance and tolerance. The classification analyses distinguished three groups. Group A (n = 596) included primarily men (93%) who were satisfied with the treatment (99%) and showed good observance. Group B (n = 284) was characterized by patient satisfaction, observance, improved symptoms and lower quality of life than group A. Group C was composed of older patients who were satisfied with their treatment and showed good observance but who had no notable improvement in their symptoms. In conclusion, this study pointed out the difficulty in defining which patients with obstructive sleep apnea would benefit most from continuous positive pressure therapy. Good observance is not a sufficient criterion for therapeutic efficacy.

Adult↗
PubMed1998

A French survey of 3,225 patients treated with CPAP for obstructive sleep apnoea: benefits, tolerance, compliance and quality of life.

The aim of this study was to investigate in a large population of patients with obstructive sleep apnoea and on long-term treatment with continuous positive airway pressure (CPAP) the patients' perception of symptomatic improvement, side-effects and quality of life. Questionnaires were mailed via local respiratory homecare associations to 5,339 French patients who had been treated at home for at least 6 months with CPAP machines and who continued their treatment. In total, 3,225 questionnaires were analysable. More than 80% of the responding patients reported that CPAP treatment had greatly improved their symptoms. Despite discomfort related to nasal problems and excess noise from the blower, the mean rate of use for the whole population was 6 h 36 min+/-2 h 15 min. The perceived health evaluated by the Nottingham Health Profile was good (mean score <50) for at least 75% of the patients in each dimension explored. The perceived health was significantly related to the improvement in symptoms, the overall satisfaction and the objective compliance. This retrospective study indicates that patients who continued continuous positive airway pressure treatment for more than 6 months felt a great improvement in their symptoms, were satisfied with the treatment and had a relatively good perception of their health.

Adult↗
PubMed1997

Accidents in obstructive sleep apnea patients treated with nasal continuous positive airway pressure: a prospective study. The Working Group ANTADIR, Paris and CRESGE, Lille, France. Association Nationale de Traitement à Domicile des Insuffisants Respiratoires.

Many studies have shown a relationship between obstructive sleep apnea (OSA) and accidents, but to our knowledge, none have investigated prospectively the effects of treatment with nasal continuous positive airway pressure (CPAP). CPAP was proposed to 973 patients, of whom 893 patients actually underwent CPAP. These patients were consecutively invited to enter a prospective follow-up study including a questionnaire before treatment and after 6 and 12 months of treatment; 547 patients completed the study (153 left the study, and only partial data were available for 193). The baseline questionnaire included questions concerning accidents in the previous 12 months, asking whether patients had had an accident and, if so, whether they felt that the accident(s) were related to sleepiness, and whether the patients felt that they had had near-miss accidents due to sleepiness. The questionnaires at 6 and 12 months included the same questions referring to the previous 6 months; the accidents reported on each follow-up questionnaire were cumulated and compared with the accidents during the 1-year period before treatment. The number of patients having an accident decreased with treatment for real accidents (from 60 to 36; p<0.01), as well as for near-miss accidents (from 151 to 32; p<0.01). The average number of accidents per patient also decreased, for real accidents (from 1.6+/-1.3 to 1.1+/-0.3; p<0.01) and for near-miss accidents (from 4.5+/-6.5 to 1.8+/-1.4; p<0.01). The cost, in terms of days in hospital related to accidents, decreased from 885 to 84 days. With caution due to the absence of a control group, it is suggested that treatment with CPAP decreases the number of accidents occurring in OSA patients. This result may have important implications in the evaluation of the cost/benefit ratio when treating OSA patients.

Accidents↗
PubMed1997

[Educational diagnosis in asthma. Descriptive results of a questionnaire survey].

The object of this work was to carry out an audit on an asthmatic's knowledge of their disease and of the risk factors, their usual therapy and of therapy for acute exacerbations as well as their need for information and education. The study was carried out by a survey of 327 adult asthmatics who were in consultation with specialist physicians in thoracic medicine. The information was gathered using an anonymous questionnaire completed by a nurse. The doctors looking after these patients had given their opinion on the severity of their asthma and the educational needs of their patients. The population studied had an average of 47 +/- 17 years. Forty seven per cent of the subjects were masculine. The general level of education was high. Seventy five per cent of the patients were from an urban environment. The duration of the asthma was on an average of 19 years. Half of these patients had already been in hospital for a serious attack. One third of the patients were considered by their doctors as having severe asthma. The patients were good at distinguishing the level of severity of their acute exacerbations and adapted their therapy on their own initiative in appropriate fashion based on the degree of severity of their disease. The enquiry revealed that patients take some liberties around the basic treatment that they had been prescribed. It also showed some defects or errors in their knowledge of the disease and the appropriate approach vis-à-vis the disease. One noted for example that one third of the asthmatics had already stopped the treatment before the date fixed by their doctor. In a general, patients who were surveyed were interested in their health problems with their health and hoped to be better informed both on asthma and its treatment. This study was biased towards an interest in the understanding of the education in order to manage the asthmatic population better.

Adolescent↗
PubMed1996

Altered trabecular architecture induced by corticosteroids: a bone histomorphometric study.

Prolonged corticosteroid (CS) therapy induces osteoporosis and fractures. Osteoporosis is characterized at the histomorphometric level by reduced bone volume (BV/TV) and disruption of the three-dimensional (3D) trabecular architecture. Several stereological methods have been proposed to characterize these alterations: measurements of trabecular thickness and trabecular number, star volumes, interconnectivity index (ICI) of the bone marrow spaces, and trabecular bone pattern factor (TBP(f)). These methods were computerized with a single program running on an image analyzer to evaluate the bone changes in a series of iliac biopsies performed on 31 male patients. All of them were asthmatic and had received CS for a long period of time. BV/TV was reduced when compared with age-matched controls. In the CS-treated population, exponential relationships were obtained between bone volume and the different connectivity parameters. The various methods used to measure connectivity were well correlated. When the population was divided into two groups (BV/TV greater or less than an 11% threshold), the architectural disturbances were found to imply two mechanisms. A progressive decline in trabecular thickness was noted in both groups versus controls. Trabecular perforations were not established in the group with BV/TV> 11% with the star volume or ICI, although some alterations were detected by trabecular bone pattern factor measurement. However, perforations were revealed in the group with BV/TV < 11% by all the different methods. Perforations seemed to occur when the trabecular thickness was below 70 mu m. This strongly suggests that bone histomorphometry should take into consideration bone volume in combination with detailed 3D descriptors of the trabecular architecture. Several histological methods need to be used in combination to appreciate the 3D architecture of trabecular bone.

Adrenal Cortex Hormones↗
PubMed1996

Seventy-two hour comparison of methylprednisolone suleptanate and methylprednisolone sodium succinate in patients with acute asthma.

The efficacy and safety of the methylprednisolone prodrugs methylprednisolone suleptanate and methylprednisolone sodium succinate were evaluated in a multicentre, randomised, double-blind, double-dummy parallel study of 88 patients hospitalised with acute asthma. Each study drug was administered as a bolus intravenous injection of 40mg methylprednisolone equivalents every 6 hours for 48 hours. Methylprednisolone 32mg was administered orally 6 hours after the last dose. Pulmonary function, medical events, and clinical laboratory values were assessed at predefined intervals before and during the 72-hour study. The primary response measure of pulmonary function was per cent predicted forced expiratory volume in one second (FEV1) at 48 hours. Secondary response measures were peak expiratory flow rate (PEFR) and FEV1/forced vital capacity (FVC) ratio. Although both drugs demonstrated within-group mean changes from baseline (starting at 6 hours) that were statistically significant for each response, there were no statistically significant differences between the two groups. The mean percent predicted FEV1 at 48 hours and mean per cent change from baseline were 64% and 13% (p < 0.0001) for the methylprednisolone suleptanate group and 67% and 17% (p < 0.0001) for the methylprednisolone sodium succinate group, respectively. The mean PEFR and FEV1/FVC ratio at 48 hours were 5.77 l/s and 73% for the methylprednisolone suleptanate group and 5.78 l/s and 76% for the methylprednisolone sodium succinate group, respectively. There were no clinically or statistically significant between-group differences in any of the safety parameters. In this study, methylprednisolone suleptanate and methylprednisolone sodium succinate have been shown to be therapeutically equivalent in the treatment of patients hospitalized with acute asthma.

Acute Disease↗
PubMed1995

Wheezes.

Wheezes are continuous adventitious lung sounds. The American Thoracic Society Committee on pulmonary nomenclature define wheezes as high-pitched continuous sounds with a dominant frequency of 400 Hz or more. Rhonchi are characterized as low-pitched continuous sounds with a dominant frequency of about 200 Hz or less. The large variability in the predominant frequency of wheezes is one of the difficulties encountered with automated analysis and quantification of wheezes. The large variations observed in automated wheeze characterization emphasize the need for standardization of breath sound analysis. This standardization would help determine diagnostic criteria for wheeze identification. The mechanism of wheeze production was first compared to a toy trumpet whose sound is produced by a vibrating reed. The pitch of the wheeze is dependent on the mass and elasticity of the airway walls and on the flow velocity. More recently, a model of wheeze production based on the mathematical analysis of the stability of airflow through a collapsible tube has been proposed. According to this model, wheezes are produced by the fluttering of the airways walls and fluid together, induced by a critical airflow velocity. Many circumstances are suitable for the production of continuous adventitious lung sounds. Thus, wheezes can be heard in several diseases, not only asthma. Wheezes are usual clinical signs in patients with obstructive airway diseases and particularly during acute episodes of asthma. A relationship between the degree of bronchial obstruction and the presence and characteristics of wheezes has been demonstrated in several studies. The best result is observed when the degree of bronchial obstruction is compared to the proportion of the respiratory cycle occupied by wheeze (tw/ttot). However, the relationship is too scattered to predict forced expiratory volume in one second (FEV1) from wheeze duration. There is no relationship between the intensity or the pitch of wheezes and the pulmonary function. The presence or quantification of wheezes have also been evaluated for the assessment of bronchial hyperresponsiveness. Wheeze detection cannot fully replace spirometry during bronchial provocation testing but may add some interesting information. Continuous monitoring of wheezes might be a useful tool for evaluation of nocturnal asthma and its treatment.

Asthma↗
PubMed1994

[Bronchial hyperreactivity in 1994, a cheerful quinquagenarian. Conclusions].

A review is made of the principal themes that are discussed in this supplement of the Revue des Maladies Respiratoires. Three important questions on bronchial hyperresponsiveness, a key feature of asthma, are raised: 1) the clinical usefulness of its assessment, mostly in the atypical forms of asthma and in occupational asthma and, less so, to estimate the severity of asthma; data derived from the Bayesian analysis lead to the conclusion that it is a test which is better for excluding rather than for confirming asthma; in an epidemiological setting, the assessment of bronchial responsiveness should be carried out to assess both host factors and the effect of environmental exposure; 2) the method of assessment which should take into account the stimulus, be it pharmacological or not, the physiological index used to assess the response and the mode of expression of results; 3) finally, the mechanisms of bronchial responsiveness are probably multiple as examined in different chapters of this supplement.

Asthma↗
PubMed1993

[Chronic respiratory diseases from tobacco use].

Cigarette smoke exerts significant deleterious effects on both lung structures and function. Tobacco alone is the most important risk factor for the development of chronic obstructive lung disease (COLD). The responsibility of smoking for the occurrence of COLD has been demonstrated by epidemiological studies and anatomicopathological findings. Smoking-related lesions initially involve the small airways and remain silent for a long time. There are still uncertainties concerning the mechanisms through which some smokers develop clinical COLD. The clinical diagnosis of COLD rests on the demonstration of dyspnoea by meticulous questioning. Only respiratory function tests can assert the presence of bronchial obstruction. These tests also are necessary to evaluate the severity of the disease, determine its prognosis and follow up its course. In clinical practice the early diagnosis of COLD rests on repeated measurements of FEV1 in smokers.

Forced Expiratory Volume↗
PubMed1991

[The analysis of bronchial obstruction and its reversibility after bronchodilators using a study of "density-effect" on maximum flow].

The change in maximal expiratory flows after inhalation of gases of various physical properties is studied since 1963. The Montreal team proposed in 1972 the helium-to-air difference in maximal expiratory flows at low lung volumes (delta He) and the volume at which the flows breathing air and the helium-oxygen mixture (the "volume isoflow" - Viso V) as "sensitive tests" for the detection of peripheral airway obstruction. "Density-dependence" (DD) has been widely used subsequently in the study of the site of bronchial obstruction in asthmatics in smokers, in subjects with early chronic bronchitis, subjects with occupational exposures to respiratory irritants, etc. The site of action of bronchodilators according to their nature or route of administration (atropine derivates acting on "central airways", "global" bronchodilation obtained by parenteral administration) was studied using DD. However, the interpretation of these studies was always based on Mead's "equal pressure point" concept minimizing the role played by bronchial wall compliance as put forward by Pride and coll. (1967). The results of certain experimental or clinical studies was found not to agree with the original explanations. Finally, the model of flow limitation recently described by Dawson and Elliott (1977) takes into account gas density and bronchial wall elasticity which determine the speed of waves propagating against flow in elastic tubes, the site of "choke points" and the cross-sectional airway area at this level. Besides methodological problems, the complex nature of mechanisms controlling bronchial flow with gases of different densities and the unavoidable influence of bronchodilators or bronchial wall compliance are major limiting factors for the use of DD in the study of the site of airflow obstruction, and effect of bronchodilator action.

Airway Obstruction↗
PubMed1989

Diagnostic value of reversibility of chronic airway obstruction to separate asthma from chronic bronchitis: a statistical approach.

Our aim was to assess the usefulness of tests of reversibility of airways obstruction (AO) in the differential diagnosis of asthma (A) and chronic bronchitis (CB). We selected on strict clinical criteria 20 CB and 32 A patients with stable AO and measured maximal forced expiratory flows before and after increasing doses of inhaled salbutamol. The highest sensitivity (Se), specificity (Sp) and likelihood ratio (L) were obtained when the improvement in forced expiratory volume in one second (FEV1) was expressed as a percentage of predicted FEV1. Se, Sp and L were 0.97, 0.95 and 19.3 (highest possible L: 20) for an increase of 10% of predicted FEV1 on 0.2 mg of salbutamol, and 1.0, 1.0 and 20, respectively, for an increase of 15% on 1 mg of salbutamol. Conversely, L was only 2.8 when the widely used increase in FEV1 of 20% over baseline was tested. In a second group of 42 unselected patients, who were referred to the laboratory for routine lung function testing with a presenting diagnosis of A or CB, L was only 5.5 when the 10% increase in predicted FEV1 was used and even lower for the classical 20% increase over baseline FEV1. We submit that routine tests of reversibility of AO have little diagnostic usefulness in unselected patients with AO and that the commonly used criteria of 15 or 20% increase in FEV1 over baseline are of no value in separating A from CB.

Albuterol↗