Study of employees with anhydride-induced respiratory disease after removal from exposure

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.

Outcome of occupational asthma after cessation of exposure: a systematic review

BACKGROUND

Patients with occupational asthma, and their medical advisers, need valid information about the prognosis of their disease.

METHODS

A systematic review of the published literature on the symptomatic and functional outcomes of occupational asthma was carried out after avoidance of exposure to the causative agent. Through a full search of electronic and bibliographic sources, original studies documenting complete recovery from asthma (n = 39,1681 patients) or improvement in non-specific bronchial hyper-responsiveness (NSBHR; n = 28,695 patients) were identified. The median duration of follow-up was 31 (range 6-240) months for studies of symptomatic recovery and 37 (6-240) months for studies of NSBHR. Most studies were of patients recruited from special clinics.

RESULTS

Reported rates of symptomatic recovery varied from 0% to 100%, with a pooled estimate of 32% (95% CI 26% to 38%). These rates were lower with increasing age (p = 0.019) and among clinic based populations (p = 0.053). Patients with the shortest durations of exposure (< or =76 months) had the highest rate of recovery (36%; 95% CI 25% to 50%), but the effect was not linear. The pooled prevalence of persistent NSBHR at follow-up was 73% (95% CI 66% to 79%). This figure was higher among patients whose disease was due to high-molecular-weight agents (p = 0.006) and, less clearly, those from clinic-based populations (p = 0.561). In between-study comparisons, no clear patterns of improvement relating to total duration of exposure or follow-up were found. From within-study comparisons there was some evidence that a shorter duration of symptoms was associated with a higher rate of symptomatic recovery.

CONCLUSION

The available data on the prognosis of occupational asthma are insufficiently consistent to allow confident advice to be given to patients with the disease. Clinicians and epidemiologists with an interest in this disease should consider a collaborative and carefully standardised study of the prognosis of occupational asthma.

The prognosis of occupational asthma due to detergent enzymes: clinical, immunological and employment outcomes

BACKGROUND

Little is known about the prognosis of occupational asthma induced by high molecular weight proteins.

OBJECTIVE

Our objective was to measure the clinical, immunological and employment outcomes of individuals with occupational asthma induced by detergent enzymes.

METHODS

We undertook a workforce-based follow-up study in 35 (78%) of the 45 ex-employees from a single factory with occupational asthma. In each case the diagnosis was supported by evidence of specific sensitization and characteristic changes in peak flow or a positive response to specific bronchial provocation testing.

RESULTS

This group had left the factory on average 37 months before study. On review 25 (71%) reported chest symptoms during the last month. Compared with when working at the factory, most (86%) reported that their symptoms had improved. Twenty continued to attend their general practitioner for respiratory symptoms and 19 still used asthma medications. Since leaving the factory 16 (46%) and four (11%) had found full-time or part-time employment, respectively; of these 16 found they were paid less than when they worked at the factory. The remaining 15 subjects had not had any paid employment. All but two had positive skin prick tests to one or more three detergent enzymes. The estimated half-life of serum-specific IgE antibodies was 20 months for protease, and 21 months for cellulase and amylase.

CONCLUSIONS

Population-based follow-up studies of the prognosis of occupational asthma are rare but probably avoid the bias in clinic-derived surveys. This study demonstrates that 3 years after the avoidance of exposure with detergent enzymes most patients continue to be troubled by, albeit improved, symptoms and experience difficulty in re-employment.

Effect of respiratory protective devices on development of antibody and occupational asthma to an acid anhydride

STUDY OBJECTIVES

To determine whether the use of respiratory protective equipment would reduce the incidence of occupational asthma due to exposure to hexahydrophthalic anhydride (HHPA).

DESIGN

Prospective cohort study.

SETTING

A facility that makes an epoxy resin product requiring HHPA for its manufacture.

PARTICIPANTS

Sixty-six individuals newly hired at a facility that makes an epoxy resin product requiring HHPA for its manufacture.

INTERVENTION

Employees who wished to use respiratory protective equipment could choose from three types of masks: dust mask, half-face organic vapor respirator, or full-face organic vapor respirator.

MEASUREMENTS

Workers were evaluated annually for development of positive antibody to HHPA and occupational, immunologic respiratory disease, including occupational asthma.

RESULTS

With use of respiratory protective equipment, the rate of developing an occupational immunologic respiratory disease was reduced from approximately 10 to 2% per year. Occupational asthma developed in only three individuals, and they were all in the higher exposure category. Statistically, one respirator was not superior to the others.

CONCLUSION

Respiratory protective equipment can reduce the incidence of occupational immunologic respiratory disease, including occupational asthma, in employees exposed to HHPA.