Division of Clinical Epidemiology, McGill University Health Centre, Montreal, QC, Canada.
Clinical Epidemiology Center, Research and Development Service, VA St Louis Health Care System, St Louis, MO, USA.
Eur Respir J. 2022 Jul 28;60(1). doi: 10.1183/13993003.02149-2021. Print 2022 Jul.
Exposure to ambient fine particulate matter with an aerodynamic diameter <2.5 μg·m (PM) is a risk factor for pulmonary and systemic autoimmune diseases; however, evidence on which PM chemical components are more harmful is still scant. Our goal is to investigate potential associations between major PM components and interstitial lung disease (ILD) onset in rheumatoid arthritis (RA).
New-onset RA subjects identified from a US healthcare insurance database (MarketScan) were followed for new onset of RA-associated ILD (RA-ILD) from 2011 to 2018. Annual concentrations of ambient PM chemical components ( sulfate, nitrate, ammonium, organic matter, black carbon, mineral dust and sea salt) were estimated by combining satellite retrievals with chemical transport modelling and refined by geographically weighted regression. Exposures from 2006 up to 1 year before ILD onset or end of study were assigned to subjects based on their core-based statistical area or metropolitan division codes. A novel time-to-event quantile-based g (generalised)-computation approach was used to estimate potential associations between RA-ILD onset and the exposure mixture of all seven PM chemical components adjusting for age, sex and prior chronic obstructive pulmonary disease (as a proxy for smoking).
We followed 280 516 new-onset RA patients and detected 2194 RA-ILD cases across 1 394 385 person-years. The adjusted hazard ratio for RA-ILD onset was 1.54 (95% CI 1.47-1.63) per every decile increase in all seven exposures. Ammonium, mineral dust and black carbon contributed more to ILD risk than the other PM components.
Exposure to components of PM, particularly ammonium, increases ILD risk in RA.
暴露于空气动力学直径<2.5μg·m 的环境细颗粒物（PM）是肺部和系统性自身免疫性疾病的危险因素；然而，关于哪些 PM 化学组分更有害的证据仍然很少。我们的目标是研究主要 PM 成分与类风湿关节炎（RA）中间质性肺病（ILD）发病之间的潜在关联。
从美国医疗保健保险数据库（MarketScan）中确定新诊断为 RA 的患者，从 2011 年到 2018 年对其进行新诊断为 RA 相关 ILD（RA-ILD）的随访。利用卫星反演与化学输送模型相结合，通过地理加权回归进行优化，估算出环境 PM 化学组分（硫酸盐、硝酸盐、铵、有机物、黑碳、矿物质粉尘和海盐）的年浓度。根据患者的核心统计区域或大都市分区代码，将 2006 年至 ILD 发病前 1 年或研究结束前的暴露情况分配给患者。采用新的基于时间的分位数 g（广义）计算方法，估计 RA-ILD 发病与所有七种 PM 化学组分暴露混合物之间的潜在关联，调整年龄、性别和既往慢性阻塞性肺疾病（作为吸烟的替代指标）。
我们对 280516 例新诊断为 RA 的患者进行了随访，在 1394385 人年中发现了 2194 例 RA-ILD 病例。所有七种暴露每增加一个十分位数，RA-ILD 发病的调整危险比为 1.54（95%CI 1.47-1.63）。与其他 PM 组分相比，铵、矿物质粉尘和黑碳对 ILD 风险的贡献更大。
暴露于 PM 的成分，特别是铵，会增加 RA 中的 ILD 风险。
