Identifying the triggers of OHCDs is of public health significance.
Previous investigators have found that short-term exposure to
ambient air pollution can trigger SCD or OHCD events (Forastiere
et al., 2005; Serinelli et al., 2010; Teng et al., 2014). Nevertheless,
this evidence is quite scarce in developing countries such as China,
where the air pollution problem is more severe than in developed
countries. Actually, the different air pollution mixture in China may
result in risk estimates different from those already reported in
developed countries. Outdoor temperature serves as another major
ambient risk factor affecting human health. Seasonal trends of SCD
have been widely observed, and a recent study reported that
extreme temperatures, both cold and hot, posed significant risks for
OHCDs (Chen et al., 2014). Conversely, because both ambient air
pollution and extreme temperatures increase the risk of OHCD, it is
important to also consider how in-hospital coronary deaths
(IHCDs) are affected by these ambient exposures, as IHCD also accounts
for almost one half of coronary deaths. However, few studies
have explored this issue.