Five Serum Trace Elements Associated with Risk of Cardia and Noncardia Gastric Cancer in a Matched Case–Control Study

Figures & data

Table 1 Baseline Characteristics of Gastric Cancer and Control Participants in a Chinese Matched Case–Control Study

Characteristics	Control (%) (n=299)	Cardia (%) (n=122)	Noncardia (%) (n=177)	p value^a	p value^b
Sex				0.45	0.57
Male	231 (77.3)	90 (73.4)	141 (79.7)
Female	68 (22.7)	32 (26.2)	36 (20.3)
Age (mean±std, years)	65.7±9.3	68.0±8.7	65.0±10.0	0.05	0.40
Age Group (Years)				0.01	0.57
<55	35 (11.5)	3 (2.5)	24 (13.6)
55–64	108 (36.3)	44 (36.0)	67 (37.9)
65–74	107 (35.9)	47 (38.5)	53 (29.9)
≥75	49 (16.3)	28 (23.0)	33 (18.6)
Body Mass Index (kg/m^2)				0.003	<0.0001
<18.5	27 (9.0)	21 (17.2)	44 (24.8)
18.5–24.9	229 (76.5)	94 (77.1)	125 (70.6)
≥25	43 (14.5)	7 (5.7)	8 (4.6)
Educational Level (Years)				0.0003	0.13
<7	200 (66.8)	104 (85.3)	134 (75.7)
7–9	60 (20.1)	15 (12.3)	28 (15.8)
≥ 10	39 (13.1)	3 (2.5)	15 (8.5)
Occupation				0.05	0.95
Farmer	210 (70.2)	97 (79.5)	121 (68.8)
Industrial worker	28 (9.4)	8 (6.6)	20 (11.4)
Office worker	58 (19.4)	17 (13.9)	34 (19.3)
Others	3 (1.0)		1 (0.6)
Household Income (Yuan/Month/Person)				<0.0001	<0.0001
<600	138 (46.2)	25 (20.7)	44 (25.0)
600–1000	77 (25.8)	41 (33.9)	53 (30.1)
≥1000	84 (28.1)	55 (45.5)	79 (44.9)
Tobacco Smoking				0.67	0.02
Yes	154 (51.5)	60 (49.2)	111 (63.1)
No	145 (48.5)	62 (50.8)	65 (36.9)
Alcohol Drinking
Yes	46 (15.4)	11 (9.0)	36 (20.5)	0.11	0.12
No	253 (84.6)	111 (91.0)	140 (79.5)
Family History of Gastric Cancer				1.00	0.88
Yes	53 (32.9)	17 (33.3)	22 (34.4)
No	108 (67.1)	34 (66.7)	42 (65.6)
Chronic Atrophic Gastritis				<0.0001	0.0001
Yes	22 (7.4)	29 (23.8)	33 (18.6)
No	277 (92.6)	93 (76.2)	144 (81.4)
Reflux				0.03	0.07
Yes	78 (30.2)	47 (83.9)	21 (20.8)
No	180 (69.8)	9 (16.1)	80 (79.2)
H. pylori infection				0.02	0.09
Positive	124 (45.1)	36 (31.6)	59 (36.4)
Negative	151 (54.9)	78 (68.4)	103 (63.6)

Notes: ^ap value between the control and cardia groups using the chi-square test. ^bp value between the control and noncardia groups using the chi-square test.

Table 2 Distribution of Serum Level (Median and Interquartile Range) of Trace Elements in the Study Population (n=594)

Trace elements	Controls	Cardia GC	Noncardia GC	p value^a	p value^b
Cu (median, IQR, μg/L)	927.7 (799.1–1312.5)	1014.6 (874.4–1309.2)	1000.2 (821.4–1226.3)	0.0003	0.0009
Zn (median, IQR, μg/L)	605.3 (492.76–804.54)	545.6 (394.9–729.5)	554.6 (428.8–761.7)	0.47	0.52
Se (median, IQR, μg/L)	92.14 (69.9–116.7)	90.9 (63.5–112.6)	90.2 (65.5–112.6)	0.28	0.16
Mo (median, IQR, μg/L)	1.8 (0.93–2.79)	0.93 (0.72–1.14)	0.93 (0.78–1.14)	<0.0001	<0.0001
Fe (median, IQR, μg/L)	1109.8 (890.0–1454.3)	925.4 (809.6–1121.0)	936.6 (780.3–1164.8)	<0.0001	0.97
Ca (median, IQR, mg/L)	85.1 (74.9–103.2)	66.7 (59.1–75.2)	68.9 (60.3–78.5)	<0.0001	<0.0001
Mg (median, IQR, mg/L)	19.1 (17.9–20.6)	20.1 (18.1–21.9)	19.8 (18.2–22.1)	0.08	0.11
Cu/Zn ratio (median, IQR)	1.43 (1.07–1.84)	2.16 (1.51–2.98)	1.91 (1.53–2.46)	<0.0001	<0.0001

Notes: ^ap value comparing the mean value of trace elements between controls and gastric cardia cancers; normal distribution used the T-test, non-normal distribution used the Wilcoxon rank-sum test. ^bp value comparing the mean value of trace elements between controls and gastric noncardia cancers; normal distribution used the T-test, non-normal distribution used the Wilcoxon rank-sum test.

Table 3 Risk Assessment of Gastric Cancer, Expressed as Odds Ratio (OR) and 95% Confidence Interval (CI), in a Chinese Case–Control Study

Variables	Controls	All Gastric Cancer		Gastric Cardia Cancer		Gastric Noncardia Cancer
	N (%)	N (%)	OR^a (95% CI)	N (%)	OR^a (95% CI)	N (%)	OR^a (95% CI)
Cu (Quartile)
Q1: <799.1	74 (24.75)	55 (18.39)	1.00	20 (16.39)	1.00	35 (19.77)	1.00
Q2: 799.1–927.9	77 (25.76)	51 (17.06)	0.73 (0.30–1.83)	21 (17.2)	0.62 (0.18–2.21)	30 (16.95)	0.74 (0.22–2.48)
Q3: 927.9–1059.8	74 (24.75)	61 (20.40)	1.01 (0.44–2.34)	23 (18.9)	0.48 (0.15–1.56)	38 (21.47)	1.39 (0.48–3.90)
Q4: >1059.8	74 (24.75)	132 (44.15)	2.42 (1.10–5.32)	58 (47.5)	2.48 (0.94–6.54)	74 (41.81)	2.39 (0.84–6.86)
p for trend			0.003		0.01		0.03
Zn (Quartile)
Q1: <492.8	74 (24.75)	114 (38.13)	1.00	53 (43.44)	1.00	61 (34.46)	1.00
Q2: 492.8–650.2	76 (25.42)	75 (25.08)	0.45 (0.18–1.09)	24 (19.67)	0.40 (0.12–1.36)	51 (28.81)	0.50 (0.18–1.42)
Q3: 650.2–844.5	74 (24.75)	44 (14.72)	0.25 (0.10–0.61)	17 (13.93)	0.15 (0.03–0.43)	27 (15.25)	0.34 (0.13–0.98)
Q4: >844.2	75 (25.08)	66 (22.07)	0.59 (0.26–1.35)	28 (22.95)	0.82 (0.29–2.24)	38 (21.47)	0.56 (0.19–1.59)
p for trend			0.22		0.54		0.25
Se (Quartile)
Q1: <69.6	73 (24.41)	97 (32.44)	1.00	39 (31.97)	1.00	58 (32.77)	1.00
Q2: 69.6–92.1	74 (24.75)	67 (22.41)	0.47 (0.20–1.08)	25 (20.49)	0.95 (0.34–2.68)	42 (23.73)	0.20 (0.06–0.62)
Q3: 92.1–118.8	76 (25.42)	67 (22.41)	0.44 (0.19–1.01)	31 (25.41)	0.55 (0.17–1.70)	36 (20.34)	0.38(0.14–1.01)
Q4: >118.8	76 (25.42)	68 (22.74)	0.33 (0.15–0.75)	27 (22.13)	0.72 (0.25–2.02)	41 (23.16)	0.18 (0.07–0.51)
p for trend			0.009		0.43		0.001
Mo (Quartile)
Q1: <0.93	60 (20.00)	143 (47.83)	1.00	60 (49.18)	1.00	83 (46.89)	1.00
Q2: 0.93–1.81	89 (29.83)	137 (45.82)	0.86 (0.43–1.73)	54 (44.26)	0.78 (0.31–1.83)	83 (46.89)	0.87 (0.37–2.06)
Q3: 1.81–2.79	69 (23.05)	12 (4.01)	0.07 (0.02–0.21)	3 (2.46)	0.04 (0.004–0.29)	9 (5.08)	0.10 (0.02–0.41)
Q4: >2.79	81 (27.12)	7 (2.34)	0.06 (0.02–0.20)	5 (4.10)	0.12 (0.03–0.47)	2 (1.13)	–
p for trend			<0.0001		<0.0001		0.001
Fe (Quartile)
Q1: <890.0	74 (24.75)	122 (72.58)	1.00	51 (41.80)	1.00	71 (40.11)	1.00
Q2: 890.0–1109.8	75 (25.08)	84 (28.09)	0.43 (0.19−0.95)	34 (27.87)	0.37 (0.13–1.07)	50 (28.25)	0.53 (0.20–1.37)
Q3: 1109.8–1454.3	73 (24.41)	38 (12.71)	0.27 (0.11–0.68)	16 (13.11)	0.18 (0.05–0.70)	22 (12.43)	0.41 (0.14–1.21)
Q4: >1454.3	77 (25.76)	55 (18.39)	0.41 (0.18–0.91)	21 (17.21)	0.44 (0.16–1.21)	34 (19.21)	0.52 (0.19–1.37)
p for trend			0.07		0.17		0.25
Ca (Quartile)
Q1: <75.3	74 (24.75)	217 (72.58)	1.00	91 (74.59)	1.00	126 (71.19)	1.00
Q2: 75.3–86.1	76 (25.42)	38 (12.71)	0.06 (0.02–0.16)	14 (11.48)	0.05 (0.01–0.22)	24 (13.56)	0.06 (0.02–0.27)
Q3: 86.1–104.5	74 (24.75)	31 (10.37)	0.09 (0.03–0.25)	11 (9.02)	0.04 (0.01–0.20)	20 (11.30)	0.13 (0.04–0.40)
Q4: >104.5	75 (25.08)	13 (4.35)	0.04 (0.01–0.11)	6 (4.92)	0.06 (0.01–0.26)	7 (3.95)	0.02 (0.00–0.17)
p for trend			<0.0001		<0.0001		<0.001
Mg (Quartile)
Q1: <17.8	74 (24.75)	56 (18.73)	1.00	22 (18.03)	1.00	34 (19.21)	1.00
Q2: 17.8–19.2	75 (25.08)	61 (20.40)	0.65 (0.27–1.58)	27 (22.13)	0.99 (0.30–3.22)	34 (19.21)	0.49 (0.16–1.51)
Q3: 19.2–20.8	76 (25.42)	69 (23.08)	1.06 (0.43–2.66)	23 (18.85)	1.28 (0.36–4.49)	46 (25.99)	1.02 (0.34–3.01)
Q4: >20.8	74 (24.75)	111 (37.79)	1.31 (0.59–2.91)	50 (40.98)	1.68 (0.56–4.84)	63 (35.59)	1.26 (0.48–3.33)
p for trend			0.23		0.25		0.28
Cu/Zn ratio (Quartile)
Q1: <1.08	74 (24.75)	19 (6.35)	1.00	6 (4.92)	1.00	13 (7.34)	1.00
Q2: 1.08–1.44	76 (25.42)	48 (16.05)	1.75 (0.54–5.74)	23 (18.85)	0.65 (0.12–3.52)	25 (14.12)	4.02 (0.74–22.01)
Q3: 1.44–1.86	75 (25.08)	63 (21.07)	1.91 (0.57–6.37)	17 (13.93)	1.07 (0.22–5.20)	46 (25.99)	3.87 (0.67–22.9)
Q4: >1.86	74 (24.75)	169 (56.52)	11.70 (3.83–35.6)	76 (62.32)	9.03 (2.29–35.6)	93 (52.54)	18.82 (3.50–96.01)
p for trend			<0.0001		<0.0001		<0.0001

Notes: ^aAdjusted for age group (<45, 45–55, 56–65, 66–75, ≥76 years), sex (male, female), body mass index (<18.5, 18.5–24.9, ≥25 kg/m²), education level (<7, 7–9, ≥10 years), occupation (farmer, industrial worker, office worker, others), household income (<600, 600–1000, ≥1000 Chinese Yuan/month/person), smoking (yes, no), family history of gastric cancer (yes, no), and H. pylori infection (yes, no).