血浆同型半胱氨酸水平和生活饮食习惯与胃癌发病风险的关联研究

目的探讨江苏省扬中和宜兴市胃癌高发区人群血浆总同型半胱氨酸(tHcy)水平、生活饮食习惯与胃癌易感性的关系。方法采用以人群为基础的病例对照研究。经组织学确诊的高发区胃腺癌病例391例,并选择与病例年龄和性别频数匹配的人群对照608例,通过酶转换法定量检测血浆tHcy的浓度,比较不同tHcy水平与胃癌风险的关系,并探讨摄入蔬菜、水果、吸烟、饮酒等因素在其中的影响。结果胃癌患者血浆tHcy平均水平显著高于对照组(P=0．002)。同时按照正常对照组人群的血浆tHcy四分位数(7．9、10．1、13.7μmol／L)分类,以血浆tHcy≤7．9μmol／L为参照组,随着tHcy的增加,罹患胃癌的风险分别增加67％(调整OR=1．67,95％CI:1．12～2．48)、98％(调整OR=1．98,95％CI:1．33～2．94)和112％(调整OR=2．12,95％CI:1．44～3．15),并且呈现显著的递增趋势(x2=15．78,P<0．001)。同时摄入蔬菜、水果相对较多时可降低胃癌的发病风险。叉生分析表明,较少摄入蔬菜、水果、吸烟和饮酒者同时血浆tHcy>15．0μmol／L时罹患胃癌的风险比两种因素单独作用时的风险增强,但交互作用不显著。结论血浆高水平tHcy可增加罹患胃癌的风险,同时较少摄入蔬菜、水果、吸烟和饮酒等不良饮食生活习惯均可增加患病风险。

Study 0n the association between total plasma homocysteine levels, dietary habits and the risk of gastric cancer

OBJECTIVE: To 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. METHODS: A 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. RESULTS: The 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. CONCLUSION: These 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.