Table 4.

Cerebrovascular end points with increased risk associated with PM_2.5 exposure

Location, etc.	Time period	Outcome	Measure of PM2.5 increase	Excess risk, hazard ratio (OR), or hazard ratio (HR) (95% CI)	Reference
Short-term exposure
Gansu 25,790 cases	2014–2017	Cerebrovascular mortality	Lag4, average increase per 10 μg/m3	1.22% (0.11–2.35%)	Wu et al. (2019)
26 cities case-crossover 348,379 cases: IS: 278,980; HS: 69,399	2013–2015	Hospital admissions for stroke	Lag3, IQR	1.0% (0.7–1.4%)	Liu et al. (2017a)
Guanzhou 9066 cases	2007–2011	a) Ischemic stroke b) Hemorrhagic stroke	Lag2, IQR	a) No association b) 6.62% (1.28–12.25%)	Lin et al. (2016b)
Beijing 48,122 cases: IS 32,799; HS 13,051	2014–2016	a) Stroke mortality b) Ischemic stroke c) Hemorrhagic stroke	Average increase per 10 μg/m3	a) 0.27% (0.12–0.43%) b) 0.23% (0.04–0.42%) c) 0.37% (0.07–0.67%)	Zhang et al. (2018b)
6 cities 54,236 cases: IS: 31,457 HS: 22,779	2013–2016	Stroke mortality	Lag3, average increase per 10 μg/m3	3.07% (2.35–3.79%)	Wang et al. (2018)
Guangdong 95,562 cases	2013–2015	Ischemic stroke	Same-day exposure, IQR	1.027% (1.018–1.037%)	Guo et al. (2017)
172 cities 2,032,667 cases	2014–2016	Hospital stroke admissions	Average increase per 10 μg/m3	0.34% (0.2–0.48%)	Tian et al. (2018)
Beijing 63,956 cases	2010–2012	Ischemic stroke	Average increase per 10 μg/m3	0.31% (95% CI 0.17–0.45%)	Tian et al. (2017)
Chengdu 84, 535 cases	2013–2015	Stroke mortality	Average increase per 10 μg/m3	0.69% (0.01–1.38%)	Zeng et al. (2018)
Nationwide 1356 cases	2013–2015	First stroke	Average increase per 10 μg/m3	OR = 1.049 (95% CI 1.038–1.061)	Guan et al. (2018)
Long-term exposure
Hong Kong 66,820 aged 65+ 6733 cases	1998–2001 to 2010	First stroke	Average increase per 10 μg/m3	HR = 1.14 (95% CI 1.02–1.27)	Qiu et al. (2017)
Nationwide 12,291 ischemic stroke patients	2007–2008	Nationwide	Average increase per 10 μg/m3	HR = 1.05 (95% CI 1.02–1.09)	Chen et al. (2019)