Table 1.

Characteristics of the DTC patients and control group.

		DTC patients	Control population	P
		(n = 174)	(n = 174)
Age		43.3 ± 12.2	42.8 ± 12.3	0.692
Gender	Male	42	44	0.804
	Female	132	130
Ethnicity	Han	166	164	0.371
	Others	8	12
Marital status	Married	159	157	0.711
	Unmarried	15	17
Educational level	Low	95	91	0.667
	High	79	83
Yearly income	Low	122	128	0.475
	High	52	46
Alcohol consumption	Yes	21	22	0.871
	No	153	152
Smoking	Yes	23	24	0.875
	No	151	150
Hypertension	Yes	14	13	0.841
	No	160	161
Diabetes	Yes	9	10	0.813
	No	165	164
Myocardial infarction	Yes	4	3	0.703
	No	170	171
Stroke	Yes	4	5	0.736
	No	170	169
Asthma	Yes	12	11	0.829
	No	162	163
Kidney disease	Yes	10	12	0.660
	No	164	162
Depression	Yes	13	10	0.517
	No	161	164

low income = less than 150 thousand RMB; high income = more than 150 thousand RMB.