Do airway inflammation and airway responsiveness markers at the start of apprenticeship predict their evolution during initial training? A longitudinal study among apprentice bakers, pastry makers and hairdressers

Multivariate analysis and data mining help predict asthma exacerbations

BACKGROUND

Work-related asthma has become a highly prevalent occupational lung disorder.

OBJECTIVE

Our study aims to evaluate occupational exposure as a predictor for asthma exacerbation.

METHOD

We performed a retrospective evaluation of 584 consecutive patients diagnosed and treated for asthma between October 2017 and December 2019 in four clinics from Western Romania. We evaluated the enrolled patients for their asthma control level by employing the Asthma Control Test (ACT < 20 represents uncontrolled asthma), the medical record of asthma exacerbations, occupational exposure, and lung function (i.e. spirometry). Then, we used statistical and data mining methods to explore the most important predictors for asthma exacerbations.

RESULTS

We identified essential predictors by calculating the odds ratios (OR) for the exacerbation in a logistic regression model. The average age was 45.42 ± 11.74 years (19-85 years), and 422 (72.26%) participants were females. 42.97% of participants had exacerbations in the past year, and 31.16% had a history of occupational exposure. In a multivariate model analysis adjusted for age and gender, the most important predictors for exacerbation were uncontrolled asthma (OR 4.79, p < .001), occupational exposure (OR 4.65, p < .001), and lung function impairment (FEV1 < 80%) (OR 1.15, p = .011). The ensemble machine learning experiments on combined patient features harnessed by our data mining approach reveal that the best predictor is professional exposure, followed by ACT.

CONCLUSIONS

Machine learning ensemble methods and statistical analysis concordantly indicate that occupational exposure and ACT < 20 are strong predictors for asthma exacerbation.

Prevention of baker's asthma

PURPOSE OF REVIEW

Baker's allergy and asthma continue to represent an important contributor of occupational asthma globally. This review identified recent studies related to the prevention of baker's allergy and asthma.

RECENT FINDINGS

Studies with respect to regulatory exposure standards, workplace control measures aimed at reduction of flour dust exposures, surveillance programmes (exposure monitoring, medical surveillance) and workplace information, education and training programmes were identified.

SUMMARY

Detailed knowledge on risk factors and detection methods to assess exposure and early identification of high-risk workers exist, but workplace control measures remain sub-optimal because they are rarely multifaceted. This is compounded by the lack of health-based exposure standards globally. Exposure level monitoring and medical surveillance are integral to assessing effectiveness of preventive strategies. Triage systems for optimizing the efficiency of medical surveillance programmes show promise, but need replication in different contexts. Future studies need to focus on evaluating the relevance and quantification of peak exposures in increasing risk; developing standardized respiratory questionnaires for medical surveillance; and further exploration of serial fractional exhaled nitric oxide (FeNO) measurements as an adjunct to allergic sensitization for the early identification of baker's asthma and assessing the long-term impact of interventions.

Longitudinal predictors of bronchial hyperresponsiveness and FEV1 decline in bakers

OBJECTIVE

To determine long-term predictors of bronchial hyperresponsiveness (BHR) and forced expiratory volume in one second (FEV₁) decline.

METHODS

A longitudinal study in 110 bakers in 4 industrial bakeries and 38 non-exposed workers was conducted at the workplace with a mean of 3.3 visits per subject over a period of 13 years and a mean duration of follow-up of 6 years in bakers and 8 years in non-exposed subjects. A respiratory health questionnaire was administered; occupational allergen skin prick tests, spirometry and a methacholine bronchial challenge test were performed at each visit. In each bakery, full-shift dust samples of the inhalable fraction were obtained in order to assess the exposure of each job assignment. The repeated measurements of BHR and FEV₁ were analyzed using mixed effects logistic and linear regression models in subjects seen at least twice.

RESULTS

BHR, respiratory symptoms and their simultaneous occurrence depended on the duration of exposure. FEV₁ significantly decreased with duration of exposure and BHR at a preceding visit. This result persisted when adjusting for the effect of BHR at the current visit. The measured exposure levels were not a significant predictor for any outcome. Occupational sensitization was only a predictor of a decline in FEV₁ when duration of exposure was not included.

CONCLUSION

In flour-exposed industrial bakers, length of exposure and smoking are long-term determinants of BHR and of the decrease in FEV₁. BHR at a preceding visit predicted lower FEV₁ even when accounting for the effect of BHR at the current visit.