Regional Center for Environment and Health, ARPA Emilia-Romagna, Via Begarelli 13, 41121 Modena, Italy.
Occup Environ Med. 2011 Jun;68(6):446-51. doi: 10.1136/oem.2010.058156. Epub 2010 Dec 16.
To investigate the association between Saharan dust outbreaks and natural, cardiovascular and respiratory mortality.
A case-crossover design was adopted to assess the effects of Saharan dust days (SDD) on mortality in the Emilia-Romagna region of Italy. The population under study consisted of residents in the six main towns of the central-western part of the region who died between August 2002 and December 2006. The association of Saharan dust outbreaks and PM(10) concentration with mortality was estimated using conditional logistic regression, adjusted for apparent temperature, holidays, summer population decrease, flu epidemic weeks and heat wave days. The role of the interaction term between PM(10) and SDD was analysed to test for effect modification induced by SDD on the PM(10)-mortality concentration-response function. Separate estimates were undertaken for hot and cold seasons.
We found some evidence of increased respiratory mortality for people aged 75 or older on SDD. Respiratory mortality increased by 22.0% (95% CI 4.0% to 43.1%) on the SDD in the whole year model and by 33.9% (8.4% to 65.4%) in the hot season model. Effects substantially attenuated for natural and cardiovascular mortality with ORs of 1.042 (95% CI 0.992 to 1.095) and 1.043 (95% CI 0.969 to 1.122), respectively.
Our findings suggest an association between respiratory mortality in the elderly and Saharan dust outbreaks. We found no evidence of an effect modification of dust events on the concentration-response relationship between PM(10) and daily deaths. Further work should be carried out to clarify the mechanism of action.
研究撒哈拉沙尘爆发与自然、心血管和呼吸道死亡率之间的关系。
采用病例交叉设计评估撒哈拉沙尘日（SDD）对意大利艾米利亚-罗马涅地区死亡率的影响。研究人群为 2002 年 8 月至 2006 年 12 月期间在该地区中西北部六个主要城镇居住并死亡的居民。使用条件逻辑回归调整表观温度、节假日、夏季人口减少、流感流行周和热浪天数，估计撒哈拉沙尘爆发和 PM（10）浓度与死亡率之间的关联。分析 PM（10）和 SDD 之间的交互项，以检验 SDD 对 PM（10）-死亡率浓度-反应关系的修饰作用。分别对热季和冷季进行了估计。
我们发现 SD 在 75 岁及以上人群中存在呼吸道死亡率增加的证据。在整个年度模型中，SDD 时呼吸道死亡率增加了 22.0%（95%CI4.0%至 43.1%），在热季模型中增加了 33.9%（8.4%至 65.4%）。自然和心血管死亡率的效应明显减弱，OR 分别为 1.042（95%CI0.992 至 1.095）和 1.043（95%CI0.969 至 1.122）。
我们的研究结果表明，老年人群的呼吸道死亡率与撒哈拉沙尘爆发有关。我们没有发现尘埃事件对 PM（10）与每日死亡之间的浓度-反应关系的修饰作用的证据。应进一步开展工作以阐明作用机制。
