Helicobacter pylori-related chronic gastritis as a risk factor for colonic neoplasms

Table 1 Studies investigating correlations between Helicobacter pylori infection and risk of colorectal neoplasm

Ref.	Country	Year of publication	Type of study design	No. of subjects	Measure of H. pylori status	Outcome	Crude OR (95%CI)	Adjusted OR (95%CI)
[20]	Taiwan	2010	Cross-sectional	9311	Urease test	Adenoma	-	1.37 (1.23-1.52)
[19]	South Korea	2012	Cross-sectional	2195	IgG	Adenoma	1.35 (1.10-1.66)	1.36 (1.10-1.68)
						Advanced adenoma	2.19 (1.40-3.42)	2.21 (1.41-3.48)
[17]	Japan	2011	Population-based	478	IgG	Adenoma	2.26 (1.44-3.55)	2.52 (1.57-4.05)
			Case-control
[18]	Germany	2012	Population-based	3381	IgG	Cancer	-	1.3 (1.14-1.50)
			Case-control		CagA	Cancer	-	1.35 (1.15-1.59)

H. pylori: Helicobacter pylori; IgG: Immunoglobulin G; CagA: Cytotoxin-associated gene A.

Table 2 Studies investigating correlations between Helicobacter pylori-related chronic atrophic gastritis diagnosed on the basis of pepsinogen tests and risk of colorectal neoplasm

Ref.	Country	Year of publication	Type of study design	No. of subjects	Measure of CAG status	Outcome	Crude OR or HR (95%CI)	Adjusted OR or HR (95%CI)
[14]	Japan	2007	Case-control	339	PG test	Cancer	-	OR = 1.56 (0.86-2.85)
[17]	Japan	2011	Population-based	478	PG test	Adenoma	OR 1.31 (0.89-1.93)	OR = 1.45 (0.97-2.17)
			Case-control
[24]	Italy	2012	Case-control	320	PG test + histopathology	Adenoma	-	OR = 0.59 (0.23-1.48)
						Cancer	-	OR = 1.03 (0.34-3.16)
[26]	Finland	2010	Cohort	20269	PG test + histopathology	Cancer	HR 1.00 (0.65-1.55)	HR = 0.98 (0.61-1.58)
[27]	Japan	2013	Cohort	99	PG test	Adenoma + Cancer	HR 2.02 (1.05-3.91)	HR = 2.72 (1.33-5.57)

CAG: Chronic atrophic gastritis; PG: Pepsinogen; OR: Odds ratio; HR: Hazard ratio.

Table 3 Studies investigating correlations between progression of Helicobacter pylori -related chronic gatritis and risk of colorectal neoplasm

Ref.	Country	Year of publication	Type of study design	No. of subjects	Measure of H. pylori-related gastritis	Outcome	Crude OR (95%CI)	Adjusted OR (95%CI)
[17]	Japan	2011	Population-based	478	H. pylori IgG and PG test
			Case-control		[mild CAG (Group B)]	Adenoma	2.61 (1.54-4.11)	2.81 (1.64-4.81)
[17]	Japan	2011	Population-based	478	H. pylori IgG and PG test
			Case-control		[extensive CAG (Group C)]	Adenoma	2.3 (1.38-3.83)	2.7 (1.58-4.62)
					H. pylori IgG and stricter CAG criteria
					[more extensive CAG (Group C)]	Adenoma	3.75 (1.70-8.23)	4.2 (1.88-9.40)
[25]	United States	2012	Cross-sectional	100296	Histopathology	Adenoma	1.52 (1.46-1.57)	-
				57820	(H. pylori-related gastritis)	Advanced adenoma	1.8 (1.69-1.92)	-
				51067		Cancer	2.35 (1.98-2.80)	-
[25]	United States	2012	Cross-sectional	90953	Histopathology	Adenoma	1.82 (1.71-1.94)	-
				52802	(intestinal metaplasia)	Advanced adenoma	2.02 (1.82-2.24)	-
				46882		Cancer	2.55 (1.93-3.37)	-

H. pylori: Helicobacter pylori; IgG: Immunoglobulin G; PG: Pepsinogen; CAG: Chronic atrophic gastritis; OR: Odds ratio.

Table 4 Correlation between stage of Helicobacter pylori-related chronic gatritis and risk of colorectal neoplasm

	H. pylori CAG	Controls (n = 239)	Total adenoma cases (n =239)	Proximal adenoma (n = 38)	Bilateral adenoma (n = 78)	Distal adenoma (n = 123)
Group A	(-) (-)	71	35	4	15	16
Group B	(+) (-)	105	127	18	41	68
	B1 (PG1/2 > 3)	92	103	14	34	55
	B2 (PG1/2 ≤ 3)	13	24	4	7	13
Group C	(+)	63	77	16	22	39
	C1 (PG1/2 > 2, PGI > 30)	50	53	11	15	27
	C2 (PG1/2 ≤ 2, PGI ≤ 30)	13	24	5	7	12
Adjusted OR1	(A:B) (95%CI)	1	2.81 (1.64-4.81)	3.06 (0.99-9.42)	1.85 (0.94-3.62)	3.05 (1.62-5.73)
	(A:B1) (95%CI)	1	2.36 (1.43-3.88)	2.73 (0.86-8.65)	1.74 (0.87-3.47)	2.86 (1.50-5.47)
	(A:B2) (95%CI)	1	3.78 (1.71-8.38)	5.32 (1.17-24.1)	2.66 (0.89-7.98)	4.36 (1.68-11.3)
Adjusted OR1	(A:C) (95%CI)	1	2.7 (1.58-4.62)	4.51 (1.43-14.2)	1.76 (0.83-3.74)	3.05 (1.54-6.07)
	(A:C1) (95%CI)	1	2.27 (1.29-3.99)	3.88 (1.17-12.9)	1.52 (0.67-3.45)	2.59 (1.25-5.35)
	(A:C2) (95%CI)	1	4.2 (1.88-9.40)	6.95 (1.63-29.6)	2.65 (0.87-8.05)	5.09 (1.89-13.7)

¹Adjusted for current smoking and total cholesterol by conditional logistic regression analysis. B1: Group αβ, subgroup based on less-strict criteria for PG I (≤ 70 ng/mL) and PG I/II ratio (> 3.0) or PG I (> 70 ng/mL) and PG I/II ratio (> 3.0) to detect mild inflammation; B2: Group γ, subgroup based on stricter criteria for PG I (> 70 ng/mL) and PG I/II ratio (≤ 3.0) to detect severe active inflammation; C1: Subgroup based on less strict criteria for PG I (≤ 70 ng/mL) and PG I/II ratio (≤ 3.0) to detect extensive CAG; C2: Subgroup based on stricter criteria for positive PG I (≤ 30 ng/mL) and PG I/II ratio (≤ 2.0) to detect more extensive and severe CAG; H. pylori: Helicobacter pylori; CAG: Chronic atrophic gastritis.