Brennan P, Silman A J
Arthritis and Rheumatism Council Epidemiology Research Unit, University of Manchester, England.
Am J Epidemiol. 1994 Sep 1;140(5):453-60. doi: 10.1093/oxfordjournals.aje.a117267.
The etiology of rheumatoid arthritis is explained by both genetic and hormonal environment factors. Using a survey of twins conducted in the British Isles in 1989, the authors have investigated the extent of a possible genetic-hormonal environment interaction in conferring susceptibility for rheumatoid arthritis. This was done by comparing the hormonal history of three groups of cases and controls: 1) disease-discordant monozygotic twins, thus matching cases and controls for genetic susceptibility; 2) disease-discordant dizygotic twins; and 3) a group of twins with rheumatoid arthritis who were age matched to population controls. When the medical histories of twins with rheumatoid arthritis were compared with those of population controls, both breast feeding and infertility problems appeared to be risk factors for the disease (odds ratios = 2.01 and 4.09, respectively). Also, oral contraceptive use appeared to have a protective effect (odds ratio = 0.43). However, when both monozygotic and dizygotic twins were compared, these effects were either less apparent or nonexistent. Our results therefore suggest that there does not exist any evidence of strong interaction between genetic and hormonal environment factors. More notably, in the absence of such an interaction, the comparison of both monozygotic and dizygotic discordant twins was overmatched and therefore of low power. The extent of any overmatching was measured using the kappa statistic.
类风湿性关节炎的病因可由遗传因素和激素环境因素来解释。作者利用1989年在不列颠群岛进行的一项双胞胎调查，研究了在赋予类风湿性关节炎易感性方面可能存在的遗传 - 激素环境相互作用的程度。这是通过比较三组病例和对照的激素史来完成的：1）疾病不一致的同卵双胞胎，从而使病例和对照在遗传易感性方面相匹配；2）疾病不一致的异卵双胞胎；3）一组年龄与人群对照相匹配的患类风湿性关节炎的双胞胎。当将患类风湿性关节炎的双胞胎的病史与人群对照的病史进行比较时，母乳喂养和不孕问题似乎都是该疾病的危险因素（优势比分别为2.01和4.09）。此外，使用口服避孕药似乎具有保护作用（优势比 = 0.43）。然而，当比较同卵双胞胎和异卵双胞胎时，这些影响要么不太明显，要么不存在。因此，我们的结果表明，没有证据表明遗传因素和激素环境因素之间存在强烈的相互作用。更值得注意的是，在不存在这种相互作用的情况下，同卵双胞胎和异卵双胞胎不一致情况的比较过度匹配，因此检验效能较低。使用kappa统计量来衡量任何过度匹配的程度。
