Although a winter peak has been widely noted in the incidence
of SCD and OHCA, few epidemiological studies have evaluated the
role of ambient temperature as a risk factor after excluding inherent
seasonal trends (Chen et al., 2014). Our results suggested that a
higher risk of OHCD is associated with both low and high temperatures.
Furthermore, the heat effects observed in this study were
more immediate than cold effects. These results are generally
consistent with findings based on total or cardiovascular mortality
(Ma et al., 2014).