Can the number of cigarettes smoked predict high-grade cervical intraepithelial neoplasia among women with mildly abnormal cervical smears?

OBJECTIVE: We investigated whether the number of cigarettes smoked by women who had mildly abnormal cytologic study results could identify those at risk for high-grade dysplasia. STUDY DESIGN: This was a prospective study of ail women who were referred for colposcopy with a mildly abnormal cervical smear over a 4-year period. A detailed questionnaire was completed that evaluated sociodemographic characteristics including smoking history. Colposcopy then determined the degree of disease. RESULTS: One hundred seventy-three women were referred with a mildly abnormal cervical smear. There was a significant relationship between the numbers of cigarettes smoked and the risk of high grade disease (P = .007). Once the number of cigarettes smoked daily exceeded 20, the risk of high grade cervical intraepithelial neoplasia was increased fivefold (odds ratio 5.85 [95% confidence interval 1.92 to 17.80]). CONCLUSION: Cigarette smoking is associated with a dose-dependent increased risk of cervical intraepithelial neoplasia grade 2 or 3 among women who have mildly abnormal cervical smears.