Telomere Length in Peripheral Leukocyte DNA and Gastric Cancer Risk

Lifang Hou; Sharon A. Savage; Martin J. Blaser; Guillermo Perez-Perez; Mirjam Hoxha; Laura Dioni; Valeria Pegoraro; Linda M. Dong; Witold Zatonski; Jolanta Lissowska; Wong-Ho Chow; Andrea Baccarelli

doi:10.1158/1055-9965.EPI-09-0347

DOI: 10.1158/1055-9965.EPI-09-0347 Published November 2009

Article Figures & Data

Tables

Table 1.

Characteristics of study subjects

Demographic and risk factors	Cases n (%), n = 300	Controls n (%), n = 416	P^*
Age (tertile), y
≤61	111 (37.0)	150 (36.0)
62-69	99 (33.0)	138 (33.2)
≥70	90 (30.0)	128 (30.8)	0.96
Sex
Male	199 (66.3)	269 (64.7)
Female	101 (33.7)	147 (35.3)	0.64
Education levels
Low	141 (47.0)	154 (37.0)
Medium	102 (34.0)	144 (34.6)
High	57 (19.0)	118 (28.4)	0.005
Family history of cancer
No family history	175 (58.3)	275 (66.1)
Stomach cancer	36 (12.0)	17 (4.1)
Other cancers	77 (25.7)	117 (28.1)
Unknown	12 (4.0)	7 (1.7)	<0.001
H. pylori status^†
Negative	50 (16.7)	63 (15.2)
Positive	250 (83.3)	352 (84.8)	0.59
Smoking status
Nonsmoker	85 (28.5)	166 (39.9)
Former smoker	90 (30.2)	133 (32.0)
Current smoker	123 (41.3)	117 (28.1)	<0.001
Pack-years of smoking^‡
0	85 (28.6)	166 (40.0)
0.1-30	100 (33.7)	137 (33.0)
>30	112 (37.7)	112 (27.0)	0.002
Alcohol drinking status
Nondrinker	105 (35.8)	136 (32.7)
Former drinker	95 (32.5)	62 (14.9)
Current drinker	93 (31.7)	218 (52.4)	<0.001
Total years of drinking alcohol
Nondrinker	105 (35.7)	136 (32.9)
<10	74 (25.2)	137 (33.1)
10-29	51 (17.3)	85 (20.5)
>29	64 (21.8)	56 (13.5)	0.008
Fruit intake
Daily/weekly	131 (46.3)	202 (48.7)
Several times/month	101 (35.7)	137 (33.0)
Rarely/never	51 (18.0)	76 (18.3)	0.75
Vegetables intake
Daily/weekly	141 (49.7)	250 (60.7)
Several times/month	108 (38.0)	122 (29.6)
Rarely/never	35 (12.3)	40 (9.7)	0.02
Mean (SD) RTL	1.25 (0.34)	1.34 (0.35)	0.0008^§

↵*P value obtained from a Fisher's exact test comparing cases and controls.
↵^†Negative, tested negative for IgG antibodies both to H. pylori and to cagA; positive, tested positive for either IgG antibodies to H. pylori or cagA antibody or both.
↵^‡Division into nonsmokers and low and high numbers of pack-years used the median of pack-years among smokers.
↵^§P value obtained from a Student’s t test comparing telomere length in cases and controls.

Table 2.

Relation of gastric cancer risk factors to telomere length among controls

Demographic and risk factors	n	RTL, mean (95% CI)^*	P
Age (tertile), y^†
≤61	150	1.43 (1.37-1.48)
62-69	138	1.30 (1.24-1.35)
≥70	128	1.28 (1.22-1.34)	<0.001
Sex^‡
Male	269	1.32 (1.28-1.36)
Female	147	1.38 (1.32-1.43)	0.09
Body mass index (tertile), kg/m²
≤24	138	1.36 (1.30-1.42)
24-26.8	140	1.33 (1.27-1.38)
≥26.8	142	1.33 (1.27-1.38)	0.40
Education level
Low	154	1.30 (1.25-1.36)
Medium	144	1.34 (1.28-1.39)
High	118	1.39 (1.33-1.45)	0.05
Family history of cancer
No family history	275	1.32 (1.28-1.36)
Stomach cancer	17	1.25 (1.09-1.41)
Other cancers	117	1.39 (1.33-1.45)
Unknown	7	1.52 (1.27-1.77)	0.13
H. pylori status^§
Negative	63	1.42 (1.34-1.51)
Positive	352	1.32 (1.29-1.36)	0.03
Smoking status^∥
Never	166	1.37 (1.32-1.43)
Former	133	1.33 (1.27-1.39)
Current	117	1.31 (1.25-1.37)	0.14
Pack-years of smoking^∥
0	166	1.38 (1.32-1.43)
0.1-30	137	1.36 (1.31-1.42)
>30	112	1.26 (1.20-1.33)	0.02
Total years of drinking alcohol
Nondrinker	136	1.36 (1.30-1.43)
<10	137	1.37 (1.31-1.43)
10-29	85	1.30 (1.23-1.38)
>29	56	1.26 (1.16-1.35)	0.06
Fruit
Daily/weekly	202	1.37 (1.32-1.41)
Several times/month	137	1.34 (1.29-1.40)
Rarely/never	76	1.26 (1.19-1.34)	0.04
Vegetables
Daily/weekly	250	1.35 (1.31-1.39)
Several times/month	122	1.33 (1.27-1.39)
Rarely/never	40	1.29 (1.18-1.39)	0.30

↵*RTL means estimated from multivariable models adjusting for age, gender, smoking status, and pack-years of smoking using the post-estimation command adjust in Stata 10.0.
↵^†Only adjusted for sex, smoking status, and pack-years of smoking.
↵^‡Only adjusted for age, smoking status, and pack-years of smoking.
↵^§Negative, tested negative for both IgG antibodies to H. pylori and cagA; positive, tested positive for either IgG antibodies to H. pylori or cagA antibody or both.
↵^∥Adjusted for each other.

Table 3.

Gastric cancer risk and telomere length

	RTL	Cases, n (%)	Controls, n (%)	OR (95% CI)^*
Quartile
Fourth	>1.53	60 (20.0)	104 (25.0)	1.00 (reference)
Third	1.31-1.53	56 (18.7)	104 (25.0)	0.91 (0.58-1.45)
Second	1.14-1.30	63 (21.0)	104 (25.0)	1.06 (0.67-1.67)
First	≤1.13	121 (40.3)	104 (25.0)	2.04 (1.33-3.13)
				P_trend < 0.001
Length category
Second, third, and fourth	Long	179 (59.7)	312 (75.0)	1.00 (reference)
First	Short	121 (40.3)	104 (25.0)	2.06 (1.48-2.86)
				P < 0.001

↵*Adjusted for age, gender, smoking status, and pack-years of smoking.

Table 4.

Gastric cancer risk and telomere length by known or potential risk factors

Demographic and risk factors	RTL^*	Cases, n (%)	Controls, n (%)	OR (95% CI)^†
Age (tertile), y
≤61	Long	84 (75.7)	127 (84.7)	1.00 (reference)
≤61	Short	27 (24.3)	23 (15.3)	1.61 (0.85-3.04)
62-69	Long	55 (55.6)	97 (70.3)	1.00 (reference)
62-69	Short	44 (44.4)	41 (29.7)	1.83 (1.06-3.15)
≥70	Long	40 (44.4)	88 (68.7)	1.00 (reference)
≥70	Short	50 (55.6)	40 (31.3)	2.78 (1.57-4.90)
Sex
Male	Long	113 (56.8)	199 (74.0)	1.00 (reference)
Male	Short	86 (43.2)	70 (26.0)	2.25 (1.50-3.38)
Female	Long	66 (65.3)	113 (76.9)	1.00 (reference)
Female	Short	35 (34.7)	34 (23.1)	1.77 (1.00-3.12)
H. pylori status^‡
Negative	Long	27 (54.0)	55 (87.3)	1.00 (reference)
Negative	Short	23 (46.0)	8 (12.7)	5.45 (2.10-14.1)
Positive	Long	152 (60.8)	256 (72.7)	1.00 (reference)
Positive	Short	98 (39.2)	96 (27.3)	1.78 (1.25-2.54)
Smoking status^§
Nonsmokers	Long	48 (56.5)	133 (80.1)	1.00 (reference)
Nonsmokers	Short	37 (43.5)	33 (19.9)	3.07 (1.71-5.51)
Former	Long	49 (54.4)	94 (70.7)	1.00 (reference)
Former	Short	41 (45.6)	39 (29.3)	2.02 (1.13-3.63)
Current	Long	81 (65.8)	85 (72.6)	1.00 (reference)
Current	Short	42 (34.2)	32 (27.4)	1.40 (0.79-2.45)
Pack-years of smoking^§
0	Long	48 (56.5)	133 (80.1)	1.00 (reference)
0	Short	37 (43.5)	33 (19.9)	3.07 (1.71-5.51)
0.1-30	Long	64 (64.0)	107 (78.1)	1.00 (reference)
0.1-30	Short	36 (36.0)	30 (28.9)	2.11 (1.17-3.80)
>30	Long	65 (58.0)	72 (64.3)	1.00 (reference)
>30	Short	47 (42.0)	40 (35.7)	1.39 (0.80-2.42)
Total years of drinking alcohol
Nondrinker	Long	60 (57.1)	99 (72.8)	1.00 (reference)
Nondrinker	Short	45 (42.9)	37 (27.2)	1.97 (1.13-3.44)
<10	Long	45 (60.8)	106 (77.4)	1.00 (reference)
<10	Short	29 (39.2)	31 (22.6)	2.38 (1.26-4.49)
10-29	Long	37 (72.5)	70 (82.3)	1.00 (reference)
10-29	Short	14 (27.5)	15 (17.7)	2.28 (0.93-5.60)
>29	Long	34 (53.1)	36 (64.3)	1.00 (reference)
>29	Short	30 (46.9)	20 (35.7)	1.67 (0.78-3.61)
Fruit intake
Daily/weekly	Long	82 (62.6)	162 (80.2)	1.00 (reference)
Daily/weekly	Short	49 (37.4)	40 (19.8)	2.43 (1.46-4.05)
Several times/month	Long	60 (59.4)	100 (73.0)	1.00 (reference)
Several times/month	Short	41 (40.6)	37 (27.0)	1.90 (1.08-3.34)
Rarely/never	Long	28 (54.9)	49 (64.5)	1.00 (reference)
Rarely/never	Short	23 (45.1)	27 (35.5)	1.73 (0.80-3.76)
Vegetable intake
Daily/weekly	Long	85 (60.3)	195 (78.0)	1.00 (reference)
Daily/weekly	Short	56 (39.7)	55 (22.0)	2.39 (1.51-3.81)
Several times/month	Long	66 (61.1)	85 (69.7)	1.00 (reference)
Several times/month	Short	42 (38.9)	37 (30.3)	1.63 (0.92-2.88)
Rarely/never	Long	19 (54.3)	29 (72.5)	1.00 (reference)
Rarely/never	Short	16 (45.7)	11 (27.5)	2.00 (0.73-5.50)

↵*Long: second, third, and fourth quartiles of telomere length; short: first quartile.
↵^†Adjusted for age, gender, smoking status, and pack-years of smoking.
↵^‡Negative, tested negative for IgG antibodies both to H. pylori and to cagA; positive, tested positive for either IgG antibodies to H. pylori or cagA antibody or both.
↵^§Adjusted for each other.