Table 3.

Risk estimation of association between telomere features and bladder cancer, for all subjects and stratified by age, using the median or quartile values of all subjects as cutoffs

All subject	Telomere length variation					Average telomere length
	N					N
	Case	Control	OR	(95% CI)	P	Case	Control	OR	(95% CI)	P
By median
<Median	138	100	Ref			142	96	ref
≥Median	86	153	2.22	(1.48–3.35)	<0.001	82	157	3.19	(2.07–4.91)	<0.001
By quartile
Q1	47	73	Ref			55	65	Ref
Q2	57	62	1.60	(0.88–2.91)		74	44	3.55	(1.89–6.66)
Q3	81	38	2.00	(1.11–3.62)		68	52	5.51	(2.93–10.38)
Q4	39	80	4.21	(2.27–7.79)	<0.001a	27	92	7.50	(3.83–14.67)	<0.001 a
Age ≤ 60
By median
<Median	63	40	Ref			78	47	Ref
≥Median	43	81	3.09	(1.62–5.88)	<0.001	28	74	4.99	(2.53–9.85)	<0.001
By quartile
Q1	22	34	Ref			17	32	Ref
Q2	29	26	2.17	(0.89–5.31)		33	18	2.55	(0.93–6.98)
Q3	34	14	3.74	(1.51–9.22)		45	29	6.08	(2.23–16.53)
Q4	21	47	5.79	(2.22–15.08)	0.002 a	11	42	10.26	(3.81–27.63)	<0.001 a
Age > 60
By median
<Median	75	60	Ref			64	49	Ref
≥Median	43	72	1.91	(1.09–3.36)	0.024	54	83	2.23	(1.25–3.96)	0.006
By quartile
Q1	25	39	Ref			38	33	Ref
Q2	28	36	1.34	(0.38–1.78)		41	26	4.68	(2.04–10.71)
Q3	47	24	1.49	(0.64–3.47)		23	23	5.31	(2.29–12.31)
Q4	18	33	3.26	(1.42–7.51)	0.025 a	16	50	5.30	(2.03–13.87)	<0.001 a

Odds ratios (ORs) were adjusted for age, gender, BMI, smoking status and education. The median or quartile values of all subjects were used as cutoffs when creating groups.

^a P-for-trend.