1 Department of Statistics, Hebrew University of Jerusalem , Jerusalem, Israel.
2 Department of Epidemiology, University of Michigan , Ann Arbor, Michigan, USA.
Environ Health Perspect. 2018 Sep;126(9):97003. doi: 10.1289/EHP2596.
Subclinical cardiovascular changes have been associated with ambient particulate matter (PM) exposures within hours. Although the U.S. Environmental Protection Agency continues to look for additional evidence of effects associated with sub-daily PM exposure, this information is still limited because most studies of clinical events have lacked data on the onset time of symptoms to assess rapid increased risk.
Our objective was to investigate associations between sub-daily exposures to PM and acute cardiac events using telemedicine data.
We conducted a case-crossover study among telemedicine participants [Formula: see text] of age who called a service center for cardiac-related symptoms and were transferred to a hospital in Tel Aviv and Haifa, Israel (2002-2013). Ambient [Formula: see text] and [Formula: see text] measured by monitors located in each city during the hours before the patient called with symptoms were compared with matched control periods. We investigated the sensitivity of these associations to more accurate symptom onset time and greater certainty of diagnosis.
We captured 12,661 calls from 7,617 subscribers experiencing ischemic (19%), arrhythmic (31%), or nonspecific (49%) cardiac events. PM concentrations were associated with small increases in the odds of cardiac events. For example, odds ratios for any cardiac event in association with a [Formula: see text] increase in 6-h and 24-h average [Formula: see text] were 1.008 [95% confidence interval (CI): 0.998, 1.018] and 1.006 (95% CI: 0.995, 1.018), respectively, and for [Formula: see text] were 1.003 (95% CI: 1.001, 1.006) and 1.003 (95% CI: 1.000, 1.007), respectively. Associations were stronger when using exposures matched to the call time rather than calendar date and for events with higher certainty of the diagnosis.
Our analysis of telemedicine data suggests that risks of cardiac events in telemedicine participants [Formula: see text] of age may increase within hours of PM exposures. https://doi.org/10.1289/EHP2596.
亚临床心血管变化与环境中颗粒物（PM）暴露在数小时内有关。尽管美国环境保护署继续寻找与亚日 PM 暴露相关的额外证据，但由于大多数临床事件研究缺乏症状发作时间的数据来评估快速增加的风险，因此该信息仍然有限。
我们的目的是使用远程医疗数据研究亚日 PM 暴露与急性心脏事件之间的关联。
我们对远程医疗参与者进行了病例交叉研究，这些参与者年龄在 [Formula: see text] 岁之间，他们因心脏相关症状拨打服务中心电话，并被转至以色列特拉维夫和海法的一家医院（2002-2013 年）。在患者出现症状前的数小时内，通过位于每个城市的监测器测量的环境 [Formula: see text] 和 [Formula: see text] 与匹配的对照期进行比较。我们调查了这些关联对更准确的症状发作时间和更确定的诊断的敏感性。
我们从经历缺血性（19%）、心律失常（31%）或非特异性（49%）心脏事件的 7,617 名订户中捕获了 12,661 次呼叫。PM 浓度与心脏事件发生几率的微小增加有关。例如，与 6 小时和 24 小时平均 [Formula: see text] 增加 [Formula: see text] 相关的任何心脏事件的比值比分别为 1.008 [95%置信区间（CI）：0.998，1.018] 和 1.006（95% CI：0.995，1.018），而 [Formula: see text] 则分别为 1.003（95% CI：1.001，1.006）和 1.003（95% CI：1.000，1.007）。当使用与呼叫时间匹配的暴露物而不是日历日期时，以及当诊断确定性更高时，关联更强。
我们对远程医疗数据的分析表明，年龄在 [Formula: see text] 岁之间的远程医疗参与者发生心脏事件的风险可能会在 PM 暴露后的数小时内增加。https://doi.org/10.1289/EHP2596.
