Occupational Asthma Reference

Suarthana E, Taghiakbari M, Saha-Chaudhuri P, Rifflart C, Suojalehto H, Hölttä P, Walusiak-Skorupa J, Wiszniewska M, Muñoz X, Romero-Mesones C, Sastre J, Rial MJ, Henneberger PK, Vandenplas O, The validity of the Canadian clinical scores for occupational asthma in European populations, Allergy, 2020;75:2124-2126,doi:10.1111/all.14294
(Plain text: Suarthana E, Taghiakbari M, Saha-Chaudhuri P, Rifflart C, Suojalehto H, Holtta P, Walusiak-Skorupa J, Wiszniewska M, Munoz X, Romero-Mesones C, Sastre J, Rial MJ, Henneberger PK, Vandenplas O, The validity of the Canadian clinical scores for occupational asthma in European populations, Allergy)

Keywords: SIC, oa, diagnosis, or, nsbr, prick test, model

Known Authors

Paul Henneberger, NIOSH, Morgantown, USA Paul Henneberger

Olivier Vandenplas, Universite Mont-Goginne, Yvoir Olivier Vandenplas

Joaquin Sastre, Fundacion Jimenez Diaz, Madrid Joaquin Sastre

Xavier Munoz, Barcelona Xavier Munoz

Hille Suojalehto, Finnish Institute of Occupational Health Hille Suojalehto

If you would like to become a known author and have your picture displayed along with your papers then please get in touch from the contact page. Known authors can choose to receive emails when their papers receive comments.

Abstract

Based on available resources, diagnostic tests are used in a stepwise approach starting with a detailed medical and occupational history; assessment of nonspecific bronchial hyperresponsiveness (NSBHR); and immunological sensitization with skin-prick tests (SPT) or specific immunoglobulin E to workplace agent when available. The second step includes serial assessments of NSBHR and peak expiratory flow at work and off-work, or specific inhalation challenge (SIC). As the reference test for diagnosing OA, SIC is only available in a few centers around the world. Therefore, Suarthana and colleagues developed non–SIC-based diagnostic models for OA using Quebec data of 160 symptomatic subjects who completed an SIC procedure (ie, development set).These subjects were exposed to high-molecular-weight (HMW) protein agents such as flour, laboratory animal allergens, and latex. OA was defined as a positive SIC, namely a sustained fall in forced expiratory volume in one second (FEV1) >20% from baseline value after exposure to the suspected occupational agent.
The final predictive model included age (>40 vs. =40 years); agent type (flour vs. other HMW agents); the presence of work-related rhinoconjunctivitis (yes/no); inhaled corticosteroid use (yes/no); positive SPT reaction to the specific occupational agent(s) (yes/no); and the presence of NSBHR (defined as the provocative concentration of histamine/methacholine causing a 20% decrease in FEV1 (PC20) =16 mg/mL). This final model demonstrated a good accuracy and internal validity. To facilitate its use, it was transformed into clinical scores equipped with the corresponding predicted probability of OA. Sum scores = 150 with a corresponding predicted probability of OA > 0.25 were recommended for referral cutoff with a sensitivity of 96%, specificity 59%, positive predicted value 72%, and negative predicted value 94%.
To externally validate the model, first, we calculated individual probabilities in European data using the equation from the Canadian model without any adjustments (no update method). The model demonstrated good discrimination in European data although lower than in Canadian (AUC 0.83 vs. 0.89, respectively). The Brier score was also higher in European data (0.171 vs. 0.121), but the model was still informative (ie, the maximum score for a noninformative model in a population with a 57.5% prevalence of OA was 0.24). Second, we recalibrated the intercept of the model. Finally, the intercept and coefficients were re-estimated (refitting method). Both methods did not improve the discriminative ability of the model: The AUC remained the same, although the Brier score slightly improved.

Plain text: Based on available resources, diagnostic tests are used in a stepwise approach starting with a detailed medical and occupational history; assessment of nonspecific bronchial hyperresponsiveness (NSBHR); and immunological sensitization with skin-prick tests (SPT) or specific immunoglobulin E to workplace agent when available. The second step includes serial assessments of NSBHR and peak expiratory flow at work and off-work, or specific inhalation challenge (SIC). As the reference test for diagnosing OA, SIC is only available in a few centers around the world. Therefore, Suarthana and colleagues developed non-SIC-based diagnostic models for OA using Quebec data of 160 symptomatic subjects who completed an SIC procedure (ie, development set).These subjects were exposed to high-molecular-weight (HMW) protein agents such as flour, laboratory animal allergens, and latex. OA was defined as a positive SIC, namely a sustained fall in forced expiratory volume in one second (FEV1) >20% from baseline value after exposure to the suspected occupational agent. The final predictive model included age (>40 vs. <=40 years); agent type (flour vs. other HMW agents); the presence of work-related rhinoconjunctivitis (yes/no); inhaled corticosteroid use (yes/no); positive SPT reaction to the specific occupational agent(s) (yes/no); and the presence of NSBHR (defined as the provocative concentration of histamine/methacholine causing a 20% decrease in FEV1 (PC20) <=16 mg/mL). This final model demonstrated a good accuracy and internal validity. To facilitate its use, it was transformed into clinical scores equipped with the corresponding predicted probability of OA. Sum scores >= 150 with a corresponding predicted probability of OA > 0.25 were recommended for referral cutoff with a sensitivity of 96%, specificity 59%, positive predicted value 72%, and negative predicted value 94%. To externally validate the model, first, we calculated individual probabilities in European data using the equation from the Canadian model without any adjustments (no update method). The model demonstrated good discrimination in European data although lower than in Canadian (AUC 0.83 vs. 0.89, respectively). The Brier score was also higher in European data (0.171 vs. 0.121), but the model was still informative (ie, the maximum score for a noninformative model in a population with a 57.5% prevalence of OA was 0.24). Second, we recalibrated the intercept of the model. Finally, the intercept and coefficients were re-estimated (refitting method). Both methods did not improve the discriminative ability of the model: The AUC remained the same, although the Brier score slightly improved.

Full Text

Associated Questions

There are no associations for this paper.

Please Log In or Register to put forward this reference as evidence to a question.

Comments

Please sign in or register to add your thoughts.


Oasys and occupational asthma smoke logo