Homocysteine and Digestive Tract Cancer Risk: A Dose-Response Meta-Analysis

Table 2

Stratified analyses of homocysteine and digestive cancer risk.

Group	No. of comparisons	Summary OR; (95% CI)	P	I^2 (%)
Total	16	1.27(1.15-1.39)	0.798	0.0
Design
Nested case-control	11	1.16(0.99-1.37)	0.851	0.0
Case-control	5	1.33(1.18-1.49)	0.548	0.0
Location
Asia	4	1.33(1.18-1.49)	0.386	1.2
America	3	1.38(1.05-1.80)	0.440	0.0
Europe	9	1.06(0.87-1.30)	0.990	0.0
Cancer type
Esophagus cancer	4	1.31(0.89-1.93)	0.797	0.0
Gastric cancer	4	1.27(0.98-1.64)	0.152	43.3
Colorectal cancer	8	1.27(1.14-1.41)	0.780	0.0
Source of control
PB	14	1.24(1.08-1.43)	0.682	0.0
HB	2	1.29(1.14-1.47)	0.857	0.0
Material
Plasma	11	1.27(1.15-1.40)	0.533	0.0
Serum	5	1.26(0.91-1.74)	0.853	0.0
Method of measurement
HPLC	9	1.29(1.16-1.44)	0.953	0.0
GC-MS	2	0.96(0.73-1.28)	0.634	0.0
FPIA	2	1.15(0.66-2.00)	0.758	0.0
Other method	3	1.53(1.15-1.39)	0.393	0.0
Control definition
Healthy population	5	1.28(1.14-1.44)	0.850	0.0
Population free from cancer	11	1.25(1.07-1.47)	0.431	1.1

Abbreviations: PB: population-based; HB: hospital-based; HPLC: High Performance Liquid Chromatography; GC-MS: gas chromatography-mass spectrometry; FPIA: fluorescence polarization immunoassay.