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J-L Malo

Publications and source records attributed to J-L Malo.

15 recordsLinked to original sources
PubMed2006

Assessment of impairment/disability due to occupational asthma through a multidimensional approach.

Subjects with occupational asthma (OA) are often left with permanent sequelae after removal from exposure, and assessing their impairment/disability should utilise various tools. The aim of the present study was to examine whether: 1) assessment of inflammation in induced sputum is relevant to impairment; and 2) use of questionnaires on quality of life and psychological factors can be useful for the evaluation of disability. In total, 40 subjects were prospectively assessed for permanent impairment/disability due to OA 2 yrs after cessation of exposure. Impairment was assessed as follows: 1) need for asthma medication; 2) asthma severity; 3) airway calibre and responsiveness; and 4) degree of inflammation in induced sputum. Disability was assessed according to quality of life and psychological distress. There was a significant improvement in airway responsiveness and inflammation from diagnosis to the present assessment. Sputum eosinophils > or =2% and neutrophils >60% were present in eight (20%) and 12 (30%) out of all subjects, respectively, one or the other feature being the only abnormalities in 15% of subjects. Quality of life was moderately affected and there was a prevalence of depression and anxiety close to 50%. In the assessment of subjects with occupational asthma, information on airway inflammation and psychological impacts are relevant to the assessment of impairment/disability, although these findings need further investigation.

Analysis of Variance↗
PubMed2006

Airway hyperresponsiveness and risk of chest symptoms in an occupational model.

BACKGROUND: The clinical outcome of asymptomatic airway hyperresponsiveness (AHR) remains unclear. A study was undertaken to evaluate the incidence of respiratory symptoms in a cohort of asymptomatic subjects with AHR at baseline. METHODS: A 3 year prospective study involving methacholine challenge tests and serially administered questionnaires was undertaken in 769 apprentices exposed to high molecular weight allergens. Analyses were performed on 428 initially asymptomatic subjects. RESULTS: Thirty eight subjects (8.9%) were airway hyperresponsive (PC(20) < or =8 mg/ml) and asymptomatic at the start of the study. Forty four apprentices (10.3%) developed two or more respiratory symptoms unrelated to work, 13 (34.2%) in the AHR group and 31 (7.9%) in the non-AHR group (risk ratio (RR) 7.88 (95% CI 2.53 to 24.55) among subjects with AHR). The RR of developing two or more respiratory symptoms increased as the degree of PC(20) decreased with a significant trend (p<0.001). In a multivariate analysis, AHR (RR 8.33, 95% CI 2.65 to 26.16) and self-reported rhinitis on exposure to pollen through an interaction with a family history of asthma (RR 6.3, 95% CI 1.29 to 31.89) were associated with the incidence of two or more respiratory symptoms; atopy was not a significant covariate. CONCLUSION: AHR in asymptomatic subjects is an important determinant for the development of respiratory symptoms outside the workplace among apprentices exposed to high molecular weight allergens in their training environment.

Adolescent↗
PubMed2006

An ATS/ERS report: 100 key questions and needs in occupational asthma.

The second Jack Pepys Workshop on Occupational Asthma was held in Toronto, Canada, in May 2004. The present report summarises key questions and research needs as identified by the international participants. The audiotapes from the workshop discussions were summarised by the organising chairs of the Symposium and the resulting document was circulated for input from all invited workshop participants. In total, 100 key questions and research needs were identified. Identified needs included: provision of different definitions depending on the use of data; explanations for differences in frequency studies; and better characterisation of genetic and environmental determinants of occupational asthma. The role of irritants and the pathogenesis of various forms of work-related asthma need further research, and there are also questions and research needs for diagnosis, prevention and understanding of persistence and airway remodelling. In conclusion, although advances have been made in the understanding of occupational asthma and other work-related asthma, further key issues remain that need addressing.

Asthma↗
PubMed2005

Is metal fume fever a determinant of welding related respiratory symptoms and/or increased bronchial responsiveness? A longitudinal study.

BACKGROUND: The current prospective study investigated the hypothesis of metal fume fever (MFF) being a predictor for the development of respiratory symptoms and functional abnormalities. METHODS: The study consisted of a pre-exposure and two follow up assessments of 286 welding apprentices during an average period of 15 months. A respiratory and a systemic symptom questionnaire, skin prick tests to common allergens and metal salts, spirometry, and methacholine challenge tests were administered. RESULTS: Developing at least one positive skin prick test to a metallic salt solution was found in 11.8% of apprentices. Possible MFF (at least one of fever, feelings of flu, general malaise, chills, dry cough, metallic taste, or shortness of breath) was reported by 39.2% of apprentices. The presence of at least one welding related respiratory symptom (cough, wheezing, or chest tightness) suggestive of welding related asthma was reported by 13.8%. MFF was significantly associated with these respiratory symptoms (OR = 4.92, 95% CI 2.10 to 11.52), after adjusting for age, atopy, smoking, physician diagnosed asthma, and symptoms of non-welding related asthma. Apprentices with possible MFF, and no welding related respiratory symptoms suggestive of welding related asthma at the first follow up, had an increased risk of developing the latter symptoms by the second follow up visit (OR = 7.4, 95% CI 1.97 to 27.45) compared with those not having MFF. MFF was not significantly associated with an increase in bronchial responsiveness. CONCLUSION: MFF could be a predictor for the development of respiratory symptoms but not for functional abnormalities in welders.

Adult↗
PubMed2005

What are the questionnaire items most useful in identifying subjects with occupational asthma?

The present study assessed the usefulness of key items obtained from a clinical "open" questionnaire prospectively administered to 212 subjects, referred to four tertiary-care hospitals for predicting the diagnosis of occupational asthma (OA). Of these subjects, 72 (34%) were diagnosed as OA (53% with OA due to high-molecular-weight agents) according to results of specific inhalation challenges, and 90 (42%) as non-OA. Wheezing at work occurred in 88% of subjects with OA and was the most specific symptom (85%). Nasal and eye symptoms were commonly associated symptoms. Wheezing, nasal and ocular itching at work were positively, and loss of voice negatively associated with the presence of OA in the case of high-, but not low molecular-weight agents. A prediction model based on responses to nasal itching, daily symptoms over the week at work, nasal secretions, absence of loss of voice, wheezing, and sputum, correctly predicted 156 out of 212 (74%) subjects according to the presence or absence of OA by final diagnosis. In conclusion, key items, i.e. wheezing, nasal and ocular itching and loss of voice, are satisfactorily associated with the presence of occupational asthma in subjects exposed to high-molecular-weight agents. Therefore, these should be addressed with high priority by physicians. However, no questionnaire-derived item is helpful in subjects exposed to low-molecular-weight agents.

Adult↗
PubMed2003

Rhinoconjunctivitis, bronchial responsiveness, and atopy as determinants for incident non-work-related asthma symptoms in apprentices exposed to high-molecular-weight allergens.

OBJECTIVE: The aim of this study was to explore the role of rhinoconjunctivitis (RC), taking into account atopy and the level of bronchial responsiveness to methacholine, on the incidence of respiratory symptoms and in the development and/or worsening of asthma. METHODS: We examined data from a prospective study in 769 students starting exposure to high-molecular-weight occupational allergens and who were serially followed for up to 44 months. RESULTS: The presence of RC symptoms at baseline was significantly associated with an increased risk of developing shortness of breath and wheezing in atopic subjects regardless of PC20 level and in subjects with a PC20 <or= 32 mg/ml regardless of atopic status. RC symptoms were significantly associated with the development of exercise-induced respiratory symptoms. Multivariate analyses indicated that having a measurable PC20 was significantly associated with the incidence of all respiratory symptoms studied, whereas baseline seasonal RC was associated only with incident exercise-induced respiratory symptoms; atopy played a minimal role, and only through an interaction with seasonal RC. CONCLUSION: Of the three potential factors for the development of respiratory symptoms that we considered, i.e. RC symptoms, having a measurable PC20 and atopy, having a measurable PC20 is the most significant one.

Adolescent↗
PubMed2003

Prevalence and association of welding related systemic and respiratory symptoms in welders.

BACKGROUND: The prevalence of welding related respiratory symptoms coexisting with welding related systemic symptoms in welders is unknown. AIMS: To determine in a sample of welders the prevalence of coexisting welding related systemic symptoms indicative of metal fume fever (MFF) and welding related respiratory symptoms suggestive of occupational asthma (OA), and the strength and significance of any association between these two groups of symptoms. METHODS: A respiratory symptoms questionnaire, a systemic symptoms questionnaire, and a questionnaire on occupational history were administered by telephone to 351 of a sample of 441 welders (79.6%) from two cities in Québec, Canada. RESULTS: The co-occurrence of possible MFF (defined as having at least two symptoms of fever, feelings of flu, general malaise, chills, dry cough, metallic taste, and shortness of breath, occurring at the beginning of the working week, 3-10 hours after exposure to welding fumes) together with welding related respiratory symptoms suggestive of OA (defined as having at least two welding related symptoms of cough, wheezing, and chest tightness) was 5.8%. These two groups of symptoms were significantly associated (chi(2) = 18.9, p < 0.001). CONCLUSION: There is a strong association between welding related MFF and welding related respiratory symptoms suggestive of OA. As such, MFF could be viewed as a pre-marker of welding related OA, a hypothesis that requires further investigation.

Adult↗
PubMed2002

Incidence and host determinants of work-related rhinoconjunctivitis in apprentice pastry-makers.

BACKGROUND: The authors recently assessed the incidence and determinants of immunologic sensitization to flour in apprentice pastry-makers. The aim of this work was to determine the incidence of work-related rhinoconjunctivitis (RC) symptoms and their determinants. METHODS: For this 188/230 entrants (81.7%) were evaluated before starting exposure to flour, and again 10.8 and 16.8 months after. Questionnaires and skin prick testing to common and work-related allergens were administered at each visit. Bronchial responsiveness to methacholine was assessed at baseline in all subjects and in a subgroup at follow-up. RESULTS: Thirty subjects (16.1%) reported new work-related RC symptoms (13.1 per 100 person-years); in three subjects (1.6%), these were accompanied by incident skin prick test reactivity to flour-derived allergens. Skin prick test reactivity to grass pollens (OR = 3.0, 95% CI, 1.3-6.7) and to pets (OR = 2.5, 95% CI, 1.1-5.9), persistent rhinitis (OR = 3.1, 95% CI, 1.1-8.4), seasonal RC (OR = 2.5, 95% CI, 1.1-5.5), RC on contact with pets (OR = 2.3, 95% CI, 1.03-5.0) and skin prick test reactivity to wheat flour (OR = 10.5, 95% CI, 2.3-46.8), assessed at baseline, were significantly associated with the incidence of work-related RC symptoms. Multivariate logistic regression analysis yielded significant OR of skin prick test reactivity to wheat flour at baseline (OR = 7.1, 95% CI, 1.7-35.1) and persistent rhinitis (OR = 3.9, 95% CI, 1.01-9.6) for the incidence of work-related RC symptoms. Increased bronchial hyperresponsiveness at follow-up was more frequent, although not significantly, in subjects positive to skin prick test to flour on entry and reporting new work-related symptoms (3/5), than in other subjects (4/17). CONCLUSIONS: The incidence of work-related RC symptoms among apprentice pastry-makers was high (16.1% 30/186), while a minority (3/30) also developed skin prick test reactivity to flour. Skin prick test reactivity to wheat flour and persistent allergic rhinitis on starting exposure to flour are significant determinants for the development of work-related RC symptoms.

Adolescent↗
PubMed2002

Interpretation of occupational peak flow records: level of agreement between expert clinicians and Oasys-2.

BACKGROUND: Oasys-2 is a validated diagnostic aid for occupational asthma that interprets peak expiratory flow (PEF) records as well as generating summary plots. The system removes inconsistency in interpretation, which is important if there is limited agreement between experts. A study was undertaken to assess the level of agreement between expert clinicians interpreting serial PEF measurements in relation to work exposure and to compare the responses given by Oasys-2. METHOD: 35 PEF records from workers under investigation for suspected occupational asthma were available for review. Records included details of nature of work, intercurrent illness, drug therapy, predicted PEF, rest periods, and holidays. Simple plots of PEF and the Oasys-2 generated plots were available. Experts were advised that approximately 1 hour was available to review the records. They were asked to score each work-rest-work (WRW) period and each rest-work-rest (RWR) period for evidence of occupational effect. At the end of each record scores of 0-100% were given for evidence of "asthma" and "occupational effect" for the whole record. Kappa values were calculated for each scored period and for the opinions on the whole record. The scores were converted into four groups (0-25%, 26-50%, 51-75%, 76-100%) and two groups (0-50% and 51-100%) for analysis. This is relevant to scores produced by Oasys-2. Agreement between Oasys-2 scores and each expert was calculated. RESULTS: 24 of 35 records were analysed by seven experts in the allotted time. For whole record occupational effect, median kappa values were 0.83 (range 0.56-0.94) for two groups and 0.62 (0.11-0.83) for four groups. For asthma, median kappa values were 0.58 (0-0.67) and 0.42 (0.15-0.70) for two and four groups respectively. For all WRW and RWR periods kappa values were 0.84 (0.42-0.94) and 0.70 (0.46-0.87) respectively. Agreement between Oasys-2 and individual experts showed a median kappa value of 0.75 (0.50-0.92) for two groups and 0.50 (0.39-0.70) for four groups. Kappa values for the median expert score v Oasys-2 were 0.75 for two groups and 0.67 for four groups. Agreement was poor for records with intermediate probability, as defined by Oasys-2. CONCLUSION: Considerable variation in agreement was seen in expert interpretation of occupational PEF records which may lead to inconsistencies in diagnosis of occupational asthma. There is a need for an objective scoring system which removes human variability, such as that provided by Oasys-2.

Asthma↗