OBJECTIVETo explore the relationship between total plasma homocysteine (tHcy) levels, dietary habits and susceptibility of gastric cancer (CGC) in Yangzhong and Yixing cities, the two high GC risk areas in Jiangsu province.

METHODSA population-based case-control study was conducted including 391 histologically-confirmed adenocarcinoma GC cases and 608 age and sex frequency-matched cancer-free controls. The plasma tHcy concentration was measured by enzymatic biochemical assay of homocysteine on microtiter plates, using crude lysate containing recombinant methionine 7-lyase. The relationship between different tHcy levels and risk of GC was analyzed and factors as vegetables and fruits intake, smoking and drinking status were also evaluated together with tHey levels on the risk of GC.

RESULTSThe average tHcy levels in GC cases were significantly higher than that in controls (P = 0.002). In addition, according to the quartile levels (7.9, 10.1, 13.7 micromol/L) in the controls, the risks of GC had an increase of 67% (adjusted OR = 1.67, 95% CI: 1.12-2.48), 98% (adjusted OR = 1.98, 95% CI: 1.33-2.94) and 112% (adjusted OR = 2.12, 95% CI: 1.44-3.15) compared to the lowest quartile of tHcy (< or = 7.9 micromol/L), respectively while the increasing trend was significantly noticed (chi2 = 15.78, P < 0.001). The increase of vegetables and fruits intake could decrease the risk of GC. Results from crossover analyses indicated that subjects with less vegetables and fruits intake or both smoking drinking together with plasma tHcy >15.0 micromol/L could increase the GC risk, when compared to the effect on GC risk of each factor.

CONCLUSIONThese findings supported the hypothesis that the high level of plasma tHcy and the badness dietary habits were associated to the increased risk of GC. Further larger scale and genetics involved studies on the environment and genetic factors were needed to confirm our findings.