Risk Factors for Non Hodgkin's Lymphoma in Twins

描述（由申请人提供）：非霍奇金淋巴瘤（NHL）的发病率随着时间的推移而增加，对非HIV NHL的风险因素知之甚少。有一些建议认为，适量饮酒可能具有保护作用，但这一发现在不同的研究中并不一致。超过10项研究检查了吸烟对NHL风险的影响，尽管一些研究发现与特定亚型（滤泡）相关的风险增加，但许多其他研究发现没有关联。酒精和烟草都是可以操纵的行为，因此，如果其中任何一个与风险有关，就会产生重要的公共卫生后果。另一方面，这些因素也与社会经济地位高度相关，因此容易混淆。一对双胞胎中的一个患上了NHL，另一个没有提供理想的研究对象来研究烟草和酒精对风险的影响。我们开发并维护了两个孪生注册表。一个是患有癌症和慢性病的双胞胎志愿者登记处（国际双胞胎研究，有17,000对双胞胎），另一个是基于人口的登记处（加州双胞胎研究），有136,000对。我们收到了来自国际双胞胎研究的208对NHL影响的双胞胎和来自加州双胞胎项目的136对双胞胎的完整问卷，共344对疾病不一致的双胞胎。我们提出了一个病例对照研究，其中的情况下是双胞胎NHL和控制是未受影响的双胞胎。比较将包括双胞胎之间的绝对和相对差异，包括酒精和烟草使用，身体质量指数，累积X射线次数以及过敏或哮喘史。每种暴露都有50-180对双胞胎不一致，这将使我们有80%的能力检测，比值比低至0.6，高至1.8。将使用多变量logistic回归进行SAS匹配病例对照分析。

DESCRIPTION (provided by applicant): The incidence of non-Hodgkin's lymphoma (NHL) is increasing over time and little is known about risk factors for non-HIV NHL. There is some suggestion that alcohol in moderation may be protective, but this finding is not consistent across studies. Over 10 studies have examined the effect of cigarette smoking on NHL risk and although some find an increased risk associated with a particular subtype (follicular), many other studies find no association. Both alcohol and tobacco are behaviors that can be manipulated, so if either is related to risk, there are important public health consequences. On the other hand, these factors are also highly associated with socioeconomic status and therefore subject to confounding. Twin pairs in whom one twin developed NHL and the other did not offer ideal subjects with which to study the effect of tobacco and alcohol on risk. We developed and maintain two twin registries. One is a volunteer registry of twins with cancer and chronic disease (International Twin Study, with 17,000 twin pairs), and the other is a population-based registry (California Twin Study) with 136,000 pairs. We have received completed questionnaires from 208 pairs of NHL affected twins from the International Twin Study, and 136 pairs from the California Twin Program, for a total of 344 disease-discordant twin pairs. We propose a case-control study in which the case is the twin with NHL and the control is the unaffected twin. Comparisons will include absolute and relative difference between twins with respect to alcohol and tobacco use, body mass index, cumulative number of x-rays, and history of allergy or asthma. There are 50-180 twin pairs discordant for each of these exposures, which will allow us 80% power to detect and odds ratio as low as 0.6 and as high as 1.8. A matched case-control analysis using SAS will be performed using multivariate logistic regression.