饮茶与膀胱癌关系的上海市区全人群病例对照研究

目的:研究饮茶与膀胱癌的关系。方法:1996年1月~1999年6月,在上海市区开展了一项基于全人群的膀胱癌病例-对照研究,共访问了608例膀胱癌病例和607例健康对照。采用非条件logistic回归模型计算比数比(OR)和95%可信区间(CI)来衡量饮茶与膀胱癌的关系。结果:饮茶对非吸烟男性膀胱癌有保护作用,OR=0.58(95%CI:0.33~1.00);且随着饮茶量的增加,膀胱癌的危险性降低。以从不饮茶者为参比组,每月饮茶<150 g、150~200 g和>200 g者的OR值分别为0.92(95%CI:0.40~2.15)、0.42(95%CI:0.16~1.12)和0.52(95%CI:0.27~1.00),趋势检验有统计学意义(P=0.027),分析中调整了年龄、职业、饮酒、膀胱感染和体质指数等混杂因素。在男性吸烟者中,由于吸烟因素本身的作用较强,未见饮茶的保护作用。由于样本量限制,未观察到饮茶对女性的保护作用。结论:饮茶(特别是绿茶)有可能是非吸烟男性膀胱癌的保护因素。

Tea consumption and bladder cancer risk:a population-based case-control study in urban Shanghai

Objective:To investigate the association between tea consumption and bladder cancer risk.Methods:Total 608 new cases of bladder cancer aged 25 to 74 years and 607 population controls randomly sampled by age frequency matching were involved in the population-based case-control study in urban Shanghai from January 1996 to June 1999.Information on the type, frequency and duration of tea consumption was collected via face to face interview by a validated questionnaire.The risk of bladder cancer for tea consumption was assessed using adjusted odds ratios(ORs) based on multivariate logistic regression analysis.Results:The results indicated tea drinking had protective effect against bladder cancer among non smoking males.The adjusted OR was 0.58(95%CI=0.33-1.00).The ORs decreased with increase in the amount of tea consumed.The multivariate ORs for tea drinking<150 g/month,150-200 g/month and>200 g/month was 0.92(95%CI:0.40-2.15),0.42(95%CI:0.16-1.12),and 0.52(95%CI:0.27-1.00),respectively(P for trend=0.027).The protective effect was not seen among smokers due to interference of smoking itself as a strong risk factor.The reduced risks of bladder cancer were not observed among females.Conclusion:Tea drinking(especially green tea) may be associated with reduced risk of bladder cancer for non smoking males.