[Epidemiology and etiologic agents of occupational asthma]

[An epidemiological and evolutionary profile of occupational asthma of Tunisian workers]

INTRODUCTION

This study aims to identify the epidemiological and occupational characteristics of patients with occupational asthma (OA) and to assess their clinical evolution and occupational outcomes.

METHODS

We carried out a descriptive epidemiological study over a period of five years (from 2012 to 2016) about the OA cases in the private sector reported in the Tunisian region of Zaghouan.

RESULTS

All in all, 165 OA cases were reported during the study period, representing an annual incidence of 733.3 cases per 1,000,000 workers in the private sector. Our study population was composed predominantly (85.5%) of women, whose mean age was 41.5±6.8years. More than three quarters of the affected persons were working in the automobile industry, and most illnesses (77%) were attributable to isocyanates. The mean time to onset of the respiratory symptoms was longer for low molecular weight agents (13.6±3.1years) compared to high molecular weight agents (12.0±3.9years) (P=0.0006). The majority of OA cases (66.7%) lost their jobs. Job loss was significantly more frequent among asthmatic women and workers with OA due to isocyanates. Among the 62 cases of OA for whom risk factors were eliminated, 45 nonetheless remained symptomatic.

CONCLUSION

Effective prevention strategies involving the various actors need to be implemented in work environments so as to reduce the frequency and the medico-legal repercussions of a disabling condition.

Asthma Symptoms in Bakeries at Parakou, Benin

Background and Objectives. There is a dearth of information on asthma among bakers in low-income settings. The objectives of this study were to determine (i) the prevalence of asthma symptoms, (ii) factors associated with probable occupational asthma (OA), and (iii) work habits that might lead to a dusty workplace environment, Parakou, Benin. Materials and Methods. This was a mixed methods (cross-sectional quantitative and qualitative) study carried out between March and September 2018.

[Uncontrolled occupational asthma: Talking about comorbidities]

INTRODUCTION

Occupational asthma is a disease where the pathophysiological characteristics of asthma are linked to repeated exposure to a sensitizing agent present in the workspace. Assessment of patients with severe asthma to identify and manage comorbidities improves asthma control and is recommended in international guidelines on the management of severe asthma.

CASE REPORT

We report the case of a 49-year-old patient, nonsmoker, without atopy, who had severe work-related asthma due to exposure to isocyanates, which was uncontrolled despite the avoidance of the occupational exposure and maximal medical treatment. A systematic assessment for possible comorbidities revealed gastroesophageal reflux and obstructive sleep apnea syndrome. The specific management of these two comorbidities led to an improvement of asthma control with a reduction in the number of exacerbations, a reduced burden of treatment and a resumption of employment.

CONCLUSIONS

As with all cases of severe asthma, the assessment of comorbidities must be systematic in the presence of an occupational asthma which persists after the cessation of the occupational exposure. The management of these comorbidities can lead to an improvement in asthma control and severity.

Respiratory Health in Cleaners in Northern Europe: Is Susceptibility Established in Early Life?

RATIONALE

There is some evidence that maternal smoking increases susceptibility to personal smoking's detrimental effects. One might question whether early life disadvantage might influence susceptibility to occupational exposure.

OBJECTIVES

In this cross-sectional study we investigated respiratory symptoms, asthma and self-reported chronic obstructive pulmonary disease (COPD) as related to working as a cleaner in Northern European populations, and whether early life factors influenced susceptibility to occupational cleaning's unhealthy effects.

METHODS

The RHINE III questionnaire study assessed occupational cleaning in 13,499 participants. Associations with respiratory symptoms, asthma and self-reported COPD were analysed with multiple logistic regressions, adjusting for sex, age, smoking, educational level, parent´s educational level, BMI and participating centre. Interaction of occupational cleaning with early life disadvantage (maternal smoking, severe respiratory infection <5 years, born during winter months, maternal age at birth >35 years) was investigated.

MAIN RESULTS

Among 2138 ever-cleaners the risks of wheeze (OR 1.4, 95% CI 1.3-1.6), adult-onset asthma (1.5 [1.2-1.8]) and self-reported COPD (1.7 [1.3-2.2]) were increased. The risk increased with years in occupational cleaning (adult-onset asthma: ≤1 year 0.9 [0.7-1.3]; 1-4 years 1.5 [1.1-2.0]; ≥4 years 1.6 [1.2-2.1]). The association of wheeze with cleaning activity ≥4 years was significantly stronger for those with early life disadvantage than in those without (1.8 [1.5-2.3] vs. 1.3 [0.96-1.8]; pinteraction 0.035).

CONCLUSIONS

Occupational cleaners had increased risk of asthma and self-reported COPD. Respiratory symptom risk was particularly increased in persons with factors suggestive of early life disadvantage. We hypothesize that early life disadvantage may increase airway vulnerability to harmful exposure from cleaning agents later in life.

Relationship between respiratory tract complaints, functional status, and smoking in hairdressers, auto painters, and carpenters

BACKGROUND AND AIM

It was observed that occupation and smoking increased each other's effects on the development of airway diseases. We aimed to search the relationship between respiratory symptoms, smoking, and occupation.

MATERIALS AND METHODS

225 employees in Düzce, Turkey, were applied a survey questioning respiratory complaints, pulmonary function tests (PFTs) and cotinine measurements in urine.

RESULTS

Cough (26.7%), phlegm (30.7%), and chest tightness (21.3%) were encountered more in carpenters compared to other groups and phlegm was statistically higher at significant level compared to other groups. The complaints of cough (30.4%), phlegm (27.4%), and chest tightness (21.5%) were significantly higher in individuals whose cotinine level was above 500 ng/mL and forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) ratio, maximum midexpiratory flow rate (MMFR) values were significantly lower. Dyspnea complaint of auto painters whose cotinine level was below 500 ng/mL was significantly higher and also expected MMFR% value of this group was significantly lower compared to other groups. While age had independent effect on respiratory function tests, type of the job was found to be independently effective on MMFR.

CONCLUSION

Smoking increases respiratory complaints of employees. In auto painters, the occupation causes airway disease regardless of smoking.

Screening for occupational asthma by using a self-administered questionnaire in a clinical setting

OBJECTIVE

Because of its high prevalence, early screening for occupational asthma (OA) is crucial. We aimed to evaluate the screening performance of the Occupational Asthma Screening Questionnaire-11 items (OASQ-11) in a clinical setting.

METHODS

Between January 2009 and December 2011, 169 workers referred for potential OA to our hospital completed the OASQ-11 and underwent workups to determine the final diagnosis. The discriminative abilities of the OASQ-11 as a whole and in relation to demographic and exposure parameters were determined by the area under the receiving operator characteristic curve (AUC).

RESULTS

Model 1, consisting of the OASQ's items, showed fair discrimination (AUC, 0.69; 95% confidence interval, 0.58 to 0.80). Addition of age and exposure duration to model 1 improved discrimination (AUC, 0.80; confidence interval, 0.72 to 0.88).

CONCLUSION

A simple model consisting of the OASQ-11's items, age, and exposure duration could well discriminate subjects with OA in a clinical setting.

Occupational allergic diseases in kitchen and health care workers: an underestimated health issue

OBJECTIVE

This study evaluated the frequencies of allergic symptoms and rate of upper respiratory infections during the past year in the general population, kitchen workers (KW) and health care workers (HCW).

METHODS

The European Community Respiratory Health Survey (ECRHS) was used to inquire retrospectively about asthma and asthma-like symptoms and the number of treatments required for previous upper respiratory tract infections (URTI: acute pharyngitis, acute sinusitis, etc.) during the past year for health care workers, kitchen workers, and members of the general population. Adjusted odds ratios by gender, age, and smoking status were calculated.

RESULTS

579 subjects (186 from the general population, 205 KW, and 188 HCW; 263 females, 316 males) participated in the study. Noninfectious (allergic) rhinitis was significantly higher in the HCW and KW groups than in the general population (P < 0.001). Cumulative asthma was significantly higher only in the HCW group (P < 0.05). In addition, the HCW and KW groups had significantly higher risks of ≥2/year URTI (OR: 1.59, 95% CI: 1.07-2.38 versus OR: 1.57, 95% CI: 1.05-2.38) than the general population.

CONCLUSION

Occupational allergic respiratory diseases are an important and growing health issue. Health care providers should become familiar with workplace environments and environmental causes of occupational rhinitis and asthma.

Occupational asthma: new low-molecular-weight causal agents, 2000-2010

Background. More than 400 agents have been documented as causing occupational asthma (OA). The list of low-molecular-weight (LMW) agents that have been identified as potential causes of OA is constantly expanding, emphasizing the need to continually update our knowledge by reviewing the literature. Objective. The objective of this paper was to identify all new LMW agents causing occupational asthma reported during the period 2000-2010. Methods. A Medline search was performed using the keywords occupational asthma, new allergens, new causes, and low-molecular-weight agents. Results. We found 39 publications describing 41 new LMW causal agents, which belonged to the following categories: drugs (n = 12), wood dust (n = 11), chemicals (n = 8), metals (n = 4), biocides (n = 3), and miscellaneous (n = 3). The diagnosis of OA was confirmed through SIC for 35 of 41 agents, peak expiratory flow monitoring for three (3) agents, and the clinical history alone for three (3) agents. Immunological tests provided evidence supporting an IgE-mediated mechanism for eight (8) (20%) of the newly described agents. Conclusion. This paper highlights the importance of being alert to the occurrence of new LMW sensitizers, which can elicit OA. The immunological mechanism is explained by a type I hypersensitivity reaction in 20% of all newly described LMW agents.

[Occupational asthma in the Tunisian central region: etiologies and professional status]

OBJECTIVE

To study the etiologies of occupational asthma and determine its impact on the professional status of asthmatic subjects.

METHODS

The authors carried out a descriptive study on all of the cases of asthma recognized as an occupational disease and declared in the private sector over nine years (2000-2008) in the Tunisian central region.

RESULTS

Cases (219) of occupational asthma were listed, accounting for 16.8% of all of the occupational diseases recognized during the period studied. Occupational asthma concerned young adults (40±8.2 years), with a predominance of women (67.7%). The textile sector dominated (74.9%). The majority of the employees were exposed to high molecular weight allergens (82.3%) and cotton dust was the principal offending agent (75.3%). Involuntary unemployment was observed in about half of the cases (46.6%) and was associated with an age lower or equal to 35 years (p = 0.01) and under 15 years of professional seniority (p=0.03).

CONCLUSION

Occupational asthma in the Tunisian central region prevails in the textile sector thereby justifying the reinforcement of preventive measures in this branch of industry.

Clinical and inflammatory features of occupational asthma caused by persulphate salts in comparison with asthma associated with occupational rhinitis

BACKGROUND

The relationships between asthma and rhinitis are still a crucial point in respiratory allergy and have scarcely been analysed in occupational setting. We aimed to compare the clinical and inflammatory features of subjects with occupational asthma only (OA) to subjects with OA associated to occupational rhinitis (OAR) caused by persulphate salts.

METHODS

The clinical charts of 26 subjects diagnosed in our Unit as respiratory allergy caused by ammonium persulphate (AP), confirmed by specific inhalation challenge (SIC), were reviewed. Twenty-two out of twenty-six patients underwent pre-SIC-induced sputum challenge test (IS) and 24/26 underwent nasal secretion collection and processing.

RESULTS

Twelve out of twenty-six patients received a diagnosis of OA-only and 14/26 of OAR. Duration of exposure before diagnosis, latency period between the beginning of exposure and asthma symptom onset, basal FEV(1), airway reactivity to methacholine and asthma severity did not differ in the two groups. Eosinophilic inflammation of upper and lower airways characterized both groups. Eosinophil percentage in IS tended to be higher in OAR [11.9 (5.575-13.925)%] than in OA-only [2.95 (0.225-12.5)%] (P = 0.31). Eosinophilia in nasal secretions was present both in subjects with OAR [55 (46-71)%] and in subjects with OA-only [38 (15-73.5)%], without any significant difference.

DISCUSSION

Our results indicate that OA because of ammonium persulphate coexists with occupational rhinitis in half of the patients. Unexpectedly, rhinitis did not seem to have an impact on the natural history of asthma. The finding of nasal inflammation in subjects with OA-only without clinical manifestations of rhinitis supports the united airway disease concept in occupational respiratory allergy as a result of persulphates.