Parazzini F, La Vecchia C, Negri E, Fedele L, Franceschi S, Gallotta L
Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy.
Cancer. 1992 May 1;69(9):2276-82. doi: 10.1002/1097-0142(19920501)69:9<2276::aid-cncr2820690912>3.0.co;2-q.
To evaluate risk factors for cervical intraepithelial neoplasia (CIN), data were collected in a case-control study based on 366 patients (58 with CIN class 1, 70 with CIN class 2, and 238 with CIN class 3) and 323 control subjects with normal cervical smears interviewed on selected days at the same screening clinics where cases had been identified. No relationship emerged between indicators of socioeconomic status (education and social class) and risk of mild/moderate (considered together) and severe dysplasia. A total of 55 (43%) patients with CIN class 1 or 2, 107 (45%) patients with CIN class 3, and 94 (29%) controls were current smokers. The corresponding relative risk (RR) estimates for current versus never smokers were 1.9 (95% confidence interval [CI] 1.2 to 3.0) for patients with CIN class 1 or 2 and 2.5 (95% CI 1.7 to 3.6) for patients with CIN class 3, and the risk increased with the number of cigarettes smoked per day. No relationship was observed between oral contraceptive use, parity, spontaneous or induced abortions and the risk of CIN, but patients tended to report earlier age at first birth than control subjects. Compared with women reporting their first birth before the age of 20 years, the risk estimates were 0.5 and 0.4, respectively, for patients with CIN 1 or 2 and patients with CIN 3 in women reporting first birth at 20 to 24 years of age. The risk estimates were 0.5 and 0.6 for those reporting their first birth at age 25 or later, but the trends in risk were not statistically significant. The number of sexual partners was directly associated with the risk for both histopathologic subgroups. Compared with women reporting no intercourse or their first intercourse after 22 years of age, women with first intercourse before the age 18 had a RR estimate of CIN class 1 or 2 of 2.3 and of CIN class 3 of 2.4, with the trends in risk being statistically significant. This study confirms considerable similarities in the epidemiology of mild/moderate and severe cervical dysplasia. In addition, it suggests consistency between the epidemiology of intraepithelial and invasive cervical neoplasia for risk factors that are likely to act on one of the first stages of the process of carcinogenesis (i.e., indications of sexual habits) but differences for hormone-mediated factors (i.e., reproductive variables or oral contraceptives).
为评估宫颈上皮内瘤变（CIN）的危险因素，我们开展了一项病例对照研究，收集了366例患者（58例CIN 1级、70例CIN 2级和238例CIN 3级）以及323例宫颈涂片正常的对照者的数据。这些对照者是在确诊病例的同一筛查诊所，于选定日期接受访谈的。社会经济地位指标（教育程度和社会阶层）与轻度/中度（合并考虑）及重度发育异常风险之间未发现关联。共有55例（43%）CIN 1级或2级患者、107例（45%）CIN 3级患者以及94例（29%）对照者为当前吸烟者。CIN 1级或2级患者当前吸烟者与从不吸烟者相比的相对风险（RR）估计值为1.9（95%置信区间[CI] 1.2至3.0），CIN 3级患者为2.5（95% CI 1.7至3.6），且风险随每日吸烟量增加而升高。未观察到口服避孕药使用、产次、自然流产或人工流产与CIN风险之间的关联，但患者首次生育年龄往往比对照者更早。与首次生育在20岁之前的女性相比，首次生育在20至24岁的CIN 1或2级患者及CIN 3级患者的风险估计值分别为0.5和0.4。首次生育在25岁及以后者的风险估计值为0.5和0.6，但风险趋势无统计学意义。性伴侣数量与两个组织病理学亚组的风险均直接相关。与报告无性交或22岁以后首次性交者相比，18岁之前首次性交的女性CIN 1或2级的RR估计值为2.3，CIN 3级为2.4，风险趋势具有统计学意义。本研究证实了轻度/中度和重度宫颈发育异常在流行病学上有相当多的相似之处。此外，这表明对于可能作用于致癌过程第一阶段之一的危险因素（即性行为习惯指标），上皮内和浸润性宫颈癌的流行病学具有一致性，但对于激素介导的因素（即生殖变量或口服避孕药）存在差异。
