Risk factors for cervical intraepithelial neoplasia in southwestern American Indian women

The authors assessed risk factors for cervical intraepithelial neoplasia (C IN) among southwestern American Indian women using case-control methods. Ca ses were New Mexico American Indian women with biopsy-proven grade I (n = 1 90), grade II (n = 70), or grade III (n = 42) cervical lesions diagnosed be tween November 1994 and October 1997. Controls were American Indian women f rom the same Indian Health Service clinics with normal cervical epithelium (n = 326). All subjects underwent interviews and laboratory evaluations. In terviews focused on history of sexually transmitted diseases, sexual behavi or, and cigarette smoking. Laboratory assays included polymerase chain reac tion-based tests for cervical human papillomavirus infection, tests for gon orrhea and chlamydia, wet mounts, and serologic assays for antibodies to Tr eponema pallidum, herpes simplex virus, and hepatitis B and C viruses. In m ultiple logistic regression analysis, the strongest risk factors for CIN II /III among American Indian women were human papillomavirus type 16 infectio n (adjusted odds ratio (OR) = 7.6; 95% confidence interval (CI): 2.4, 23.2) , any human papillomavirus infection (OR = 5.8; 95% CI: 3.3, 10.0), low inc ome (OR = 3.3; 95% CI: 1.7, 6.2), and history of any sexually transmitted d isease (OR = 2.0; 95% CI: 1.1, 3.5). Unlike previous research, this study f ound no strong associations between CIN and sexual activity or cigarette sm oking.