Ambient fine particulate air pollution triggers ST-elevation myocardial infarction, but not non-ST elevation myocardial infarction: a case-crossover study

Abstract

BackgroundWe and others have shown that increases in particulate air pollutant (PM) concentrations in the previous hours and days have been associated with increased risks of myocardial infarction, but little is known about the relationships between air pollution and specific subsets of myocardial infarction, such as ST-elevation myocardial infarction (STEMI) and non ST-elevation myocardial infarction (NSTEMI).MethodsUsing data from acute coronary syndrome patients with STEMI (n = 338) and NSTEMI (n = 339) and case-crossover methods, we estimated the risk of STEMI and NSTEMI associated with increased ambient fine particle (<2.5 um) concentrations, ultrafine particle (10-100 nm) number concentrations, and accumulation mode particle (100-500 nm) number concentrations in the previous few hours and days.ResultsWe found a significant 18% increase in the risk of STEMI associated with each 7.1 μg/m3 increase in PM2.5 concentration in the previous hour prior to acute coronary syndrome onset, with smaller, non-significantly increased risks associated with increased fine particle concentrations in the previous 3, 12, and 24 hours. We found no pattern with NSTEMI. Estimates of the risk of STEMI associated with interquartile range increases in ultrafine particle and accumulation mode particle number concentrations in the previous 1 to 96 hours were all greater than 1.0, but not statistically significant. Patients with pre-existing hypertension had a significantly greater risk of STEMI associated with increased fine particle concentration in the previous hour than patients without hypertension.ConclusionsIncreased fine particle concentrations in the hour prior to acute coronary syndrome onset were associated with an increased risk of STEMI, but not NSTEMI. Patients with pre-existing hypertension and other cardiovascular disease appeared particularly susceptible. Further investigation into mechanisms by which PM can preferentially trigger STEMI over NSTEMI within this rapid time scale is needed.

Short‐Term Exposure to Fine Particulate Matter Air Pollution Is Preferentially Associated With the Risk of ST‐Segment Elevation Acute Coronary Events

“…These results are somewhat consistent with a recent study using data from the University of Rochester Medical Center Cardiac Catheterization Laboratory18 that observed that increased PM 2.5 concentrations in the hour prior to ACS onset were associated with STEMI events but not with NSTEMI events. They reported that each 7.1‐μg/m 3 increase in previous‐hour PM 2.5 was associated with an 18% greater risk of STEMI, which would be an ≈26% increase per 10‐μg/m 3 increase in previous‐hour PM 2.5 .…”

“…Furthermore, without hourly concentrations, these results cannot be compared directly with the analyses that included hourly data,13, 18 and we were unable to explore lag structures with <24 hours.…”

Associations between short-term exposure to particulate matter and ultrafine particles and myocardial infarction in Augsburg, Germany

“…Yet, the proportion of men and non-diabetics was significantly higher and people were older compared to the city dwellers. A recent study reporting associations with PM 2.5 only for STEMI (Gardner et al, 2014) but not non-STEMI suggesting different underlying mechanisms how air pollution may trigger MI could not be confirmed in our analyses (nonfatal events only).…”

“…As their surface area-to-mass ratio is much larger compared to PM 10 and PM 2.5 , their potential of carrying diverse toxic materials on the surface is high. However, studies on ultrafine particles as trigger for MI are sparse Peters et al, 2005;von Klot et al, 2005;Lanki et al, 2006;Gardner et al, 2014) and often consider data collected over limited periods. Therefore, the objective of this analysis was to assess the effects of short-term exposure to PM 10 , PM 2.5 and PNC on registry-based MI cases and coronary deaths in the area of Augsburg, Germany, for the period 1995-2009.…”

Cardiovascular and Cerebrovascular Emergency Department Visits Associated With Wildfire Smoke Exposure in California in 2015

“…Myocardial infarction and ischemic heart disease appeared second at lag 1. Epidemiologic studies indicate that ambient particulate matter exposure is more strongly associated with ST‐elevation myocardial infarction than non‐ST‐elevation myocardial infarction, suggesting that the mechanism is dependent upon erosion of a rupture‐prone plaque and changes in the balance of pro‐thrombotic and anti‐thrombotic processes promoting more extensive thrombosis 37. ED visits for heart failure appeared first at lag 0 and increased with time, with the highest RR at lag 3.…”