Hu Chunshao, Cruz Maria-Jesus, Ojanguren Iñigo, de Homdedeu Miquel, Gonzalez-Barcala Francisco-Javier, Munoz Xavier
Pulmonology, Hospital General Universitario Morales Meseguer, Murcia, Spain.
Servei de Pneumologia, Hospital Universitari Vall dHebron, Institut de Recerca (VHIR), Universitat Autnoma de Barcelona, Barcelona, Spain.
Occup Environ Med. 2017 Aug;74(8):586-591. doi: 10.1136/oemed-2016-103806. Epub 2017 Mar 7.
The specific inhalation challenge (SIC) is considered the gold standard for the diagnosis of occupational asthma (OA). However, its use is not standardised, and the intensity of exposure is regulated empirically. The aim of this study was to identify clinical variables and/or pulmonary function variables able to predict the scale of patients' response to SIC.
All patients who underwent SIC at our centre between 2005 and 2013 were studied. Anthropometric characteristics, atopic status, type of causal agent, latency times, pulmonary function tests and SIC results were analysed.
Two hundred and one patients (51% men) were assessed, of whom 86 (43%) had positive SIC. In the patients with positive results, 29 (34%) were exposed to high molecular weight (HMW) agents and 57 (64%) to low molecular weight (LMW) agents. Patients with a positive SIC exposed to HMW agents had a higher fall in FEV after SIC compared with those exposed to LMW agents (p=0.036). The type of asthmatic reaction after SIC also differed between the groups (p=0.020). The logistic regression analysis showed that patients with a higher PC before SIC were less likely to have severe decreases in FEV1 after SIC after adjusting for potential confounders (OR=0.771, 95% CI 0.618 to 0.961, p=0.021).
The scale of the response to SIC is influenced mainly by the degree of bronchial hyper-responsiveness, regardless of whether the causative agent is HMW or LMW, or whether the response is early or late.
特异性吸入激发试验（SIC）被认为是职业性哮喘（OA）诊断的金标准。然而，其使用并不规范，且暴露强度是凭经验调节的。本研究的目的是确定能够预测患者对SIC反应程度的临床变量和/或肺功能变量。
对2005年至2013年间在我们中心接受SIC的所有患者进行研究。分析人体测量特征、特应性状态、致病因子类型、潜伏期、肺功能测试和SIC结果。
评估了201例患者（51%为男性），其中86例（43%）SIC结果为阳性。结果为阳性的患者中，29例（34%）暴露于高分子量（HMW）物质，57例（64%）暴露于低分子量（LMW）物质。与暴露于LMW物质的患者相比，暴露于HMW物质且SIC结果为阳性的患者在SIC后FEV下降幅度更大（p=0.036）。两组之间SIC后的哮喘反应类型也有所不同（p=0.020）。逻辑回归分析表明，在调整潜在混杂因素后，SIC前PC较高的患者在SIC后FEV1严重下降的可能性较小（OR=0.771，95%CI为0.618至0.961，p=0.021）。
对SIC的反应程度主要受支气管高反应性程度的影响，无论致病因子是HMW还是LMW，也无论反应是早期还是晚期。
