. Author manuscript; available in PMC: 2021 May 26.

Published in final edited form as: Ecotoxicol Environ Saf. 2021 Feb 24;213:112063. doi: 10.1016/j.ecoenv.2021.112063

Table 3.

Subgroup analyses for hazard ratios (95% CIs) of stroke mortality associated with each 10 μg/m³ increase in PM_2.5 levels.

Subgroup	No. of deaths	Person-years of follow-up	Hazard ratio (95%CI)^a	p-value for interaction
Age
< 65	101	339,598	1.00 (0.68–1.47)
≥ 65	153	35,750	1.58 (1.17–2.13)	0.716
Sex
Men	163	186,434	1.24 (0.93–1.66)
Women	91	189,442	1.48 (1.01–2.19)	0.143
Education
< high school level	209	212,962	1.36 (1.05–1.75)
≥ high school level	45	162,913	1.18 (0.68–2.05)	0.639

Covariates in the multivariable-adjusted models included age, sex, education, personal monthly income, BMI, smoke, alcohol drink, physical activity, history of hypertension and diabetes.