Passive cigarette smoking is a risk factor in cervical neoplasia

To determine the role of spouse's cigarette smoking in the detection of high-grade squamous intraepithelial lesions of the cervix.

Prospective cohort study with multivariate analysis.

Colposcopy clinic in a tertiary hospital.

Women referred to a colposcopy clinic for evaluation of abnormal Papanicolaou smears showing either repeated inflammatory changes, low-grade squamous intraepithelial lesion (LSIL), or high-grade squamous intraepithelial lesion (HSIL). Data collection. The women were interviewed with a structured questionnaire for sexual history, use of oral contraceptive pills, personal and spouse cigarette-smoking history, and obstetric history.

There were 623 women in the cohort. They were grouped into normal, LSIL, and HSIL categories based on colposcopy and histologic assessment. There were very few women who had had more than one sexual partner or a history of sexually transmitted diseases (STDs). The prevalence of oral contraceptive pill usage was 2.9% among the women in the normal group, 4.3% in women with LSIL, and 5.1% in women with HSIL. The incidence of cigarette smoking by the women was 2.5%, 3.2%, and 6.8% for the three groups of women, respectively. The incidence of spouse cigarette smoking was 25%, 35%, and 43% respectively. Compared to women in the normal group, women with HSIL were younger at first sexual intercourse, more likely to smoke cigarettes, and have spouses who smoked cigarettes. After controlling for age, age at first sexual intercourse, usage of combined contraceptive pills, and the woman's own cigarette-smoking habit, the odds ratio for HSIL was 1.046 for every stick of cigarette smoked by the spouse. In other words, the risk of detection of HSIL increased by 4.6% for every stick of cigarette her spouse smoked.

Among women attending a colposcopy clinic, the risk of detection of HSIL increases with the spouse's cigarette-smoking habit. Further studies are warranted in quantifying the risk in a general population.