Division of Respiratory Disease Studies, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, West Virginia, USA.
Can Respir J. 2013 May-Jun;20(3):159-64. doi: 10.1155/2013/495767.
Clinical and epidemiological studies commonly use different case definitions in different settings when investigating work-exacerbated asthma (WEA). These differences are likely to impact characteristics of the resulting WEA cases.
To investigate this issue by comparing two groups of WEA cases, one identified using an intensive clinical evaluation and another that fulfilled epidemiological criteria.
A total of 53 clinical WEA cases had been referred for suspected work-related asthma to two tertiary clinics in Canada, where patients completed tests that confirmed asthma and ruled out asthma caused by work. Forty-seven epidemiological WEA cases were employed asthma patients treated at a health maintenance organization in the United States who completed a questionnaire and spirometry, and fulfilled criteria for WEA based on self-reported, work-related worsening of asthma and relevant workplace exposures as judged by an expert panel.
Using different case criteria in different settings resulted in case groups that had a mix of similarities and differences. The clinical WEA cases were more likely to have visited a doctor's office ≥3 times for asthma in the past year (75% versus 11%; P<0.0001), but did not seek more asthma-related emergency or in-patient care, or have lower spirometry values. The two groups differed substantially according to the industries and occupations where the cases worked.
Findings from both types of studies should be considered when measuring the contribution of work to asthma exacerbations, identifying putative agents, and selecting industries and occupations in which to implement screening and surveillance programs.
在调查工作诱发哮喘（WEA）时，临床和流行病学研究通常在不同的环境中使用不同的病例定义。这些差异可能会影响到由此产生的 WEA 病例的特征。
通过比较两组 WEA 病例来研究这个问题，一组是通过强化临床评估确定的，另一组则符合流行病学标准。
共有 53 例临床 WEA 病例被转诊到加拿大的两家三级诊所，这些患者完成了测试以确认哮喘并排除了工作引起的哮喘。47 例流行病学 WEA 病例是在一家美国的健康维护组织接受治疗的哮喘患者，他们完成了一份问卷和肺活量测定，并根据自我报告的、与工作相关的哮喘恶化和专家小组判断的相关工作场所暴露，符合 WEA 的标准。
在不同的环境中使用不同的病例标准导致了病例组既有相似之处，也有不同之处。临床 WEA 病例在过去一年中因哮喘就诊医生办公室≥3 次的可能性更高（75%比 11%；P<0.0001），但没有寻求更多的哮喘相关急诊或住院治疗，或肺活量值较低。两组在病例工作的行业和职业方面存在显著差异。
在衡量工作对哮喘恶化的贡献、识别潜在的致病因子以及选择实施筛查和监测计划的行业和职业时，应考虑这两种类型的研究结果。
