For how long is WTC exposure associated with incident airway obstruction?

描述(由申请人提供)：在世贸中心(WTC)灾难现场工作的不良短期和中期呼吸影响已在纽约市消防局(FDNY)、急救人员和其他人员中得到广泛记录。我们的FDNY团队首先报告了WTC咳嗽综合征，证明了9/11事件后与工作相关的暴露增加了空气消化症状的风险长达四年，并表明呼吸道诊断的患病率，无论是自我报告的还是FDNY医生诊断的，在现场工作七到九年后仍然居高不下。然而，目前尚不清楚这些对健康的影响是在灾难现场工作后不久发生的，还是在随后的几年里不断出现新的疾病或呼吸道症状。换句话说，我们和其他人观察到的疾病累积发病率和流行症状的暴露/反应梯度可能完全归因于9/11/2001之后不久较高的发病率，而在此之后，事件影响的暴露/反应梯度不存在。我们提出了创新的统计方法-带变点的参数生存模型-来研究WTC暴露后前十年新发的阻塞性呼吸道疾病(OAD)疾病诊断和症状的发生率，目的是确定在暴露于FDNY的消防员中观察到暴露反应梯度的时间长度。这项工作将能够估计相对短期、高强度暴露可能与发生的呼吸道疾病相关的时间长度。 公共卫生相关性：如果在暴露多年后发现WTC暴露继续与OAD风险增加相关，这样的结果将支持当前的政策，即向暴露于WTC的救援/恢复人员提供针对这些情况的卫生保健，而不考虑诊断年份。另一方面，如果暴露反应梯度在这十年随访期结束时充分减弱，可能会让暴露工人放心，他们的高风险时期已经过去。最后，提出的创新方法首次允许对暴露反应关系随时间的持久性和/或衰减性进行定量估计，并将适用于许多关于短期职业或环境暴露的长期影响的额外队列研究。

DESCRIPTION (provided by applicant): Adverse short- and medium-term respiratory effects of work at the World Trade Center (WTC) disaster site have been widely documented in Fire Department of the City of New York (FDNY) first responders and others. Our FDNY team first reported WTC cough syndrome, demonstrated that work-related exposures to the disaster site increased the odds of aerodigestive symptoms up to four years post-9/11, and showed that the prevalence of respiratory diagnoses, both self-reported and FDNY-physician diagnosed, remained elevated seven to nine years after working at the site. It remains unclear, however, whether these health effects occurred shortly after working at the disaster site or if new disease or respiratory symptoms occurred continually over subsequent years. Stated differently, it is possible that the exposure/response gradient we and others have observed for the cumulative incidence of disease and prevalent symptoms can be attributed entirely to higher incidence rates shortly after 9/11/2001, and beyond that time, there is no exposure response gradient for incident effects. We propose innovative statistical methods - parametric survival models with change points - to study the incidence of new onset obstructive airway disease (OAD) disease diagnoses and symptoms over the first ten years following WTC exposure, with the goal of determining the length of time that exposure response gradients are observed among exposed FDNY firefighters. This work will allow estimation of the length of time that a relatively short-term, high intensity exposure may be associated with incident respiratory illness. PUBLIC HEALTH RELEVANCE: If WTC exposure is found to continue to be associated with elevated risk of OAD years after exposure, such a result would support current policy to provide health care for these conditions to exposed rescue/recovery workers regardless of the year of diagnosis. On the other hand, if the exposure response gradient is sufficiently attenuated by the end of this ten year follow up period, it may reassure exposed workers that their period of high risk has passed. Finally, the innovative methods proposed allow, for the first time, the quantitative estimation of persistence and/or attenuation in exposure response relationships over time, and will be applicable to many additional cohort studies of the long-term effects of short-term occupational or environmental exposures.