Table 1.

The demographic data of the study participants.

n = 160,504	Subgroups	n	%
Age (mean, SD)		40.46	14.62
Follow up years (mean, SD)		11.71	0.93
Male		70,352	43.8
Alcoholism		2477	1.5
Tobacco dependence		4503	2.8
COPD		45,407	28.3
Levels of insurance fee	Lowest	25,165	15.7
	2nd	51,927	32.4
	3rd	37,417	23.3
	Highest	45,995	28.7
Urbanization	Highest	55,306	34.5
	2nd	52,152	32.5
	3rd	27,215	17.0
	Lowest	25,831	16.1
SO2	Low	52,037	32.4
	Moderate	62,730	39.1
	High	45,737	28.5
CO	Low	56,720	35.3
	Moderate	51,023	31.8
	High	52,761	32.9
PM2.5	Low	53,235	33.2
	Moderate	53,586	33.4
	High	53,683	33.4
NO2	Low	55,071	34.3
	Moderate	54,227	33.8
	High	51,206	31.9
PM10	Low	59,636	37.2
	Moderate	50,209	31.3
	High	50,659	31.6