[Risk factors associated with abnormal cervical cytology among Chilean women: a case control study]

Cervical cancer is the third cause of cancer death among Chilean women, affecting mainly women from low socioeconomic status.

To determine main risk factors (RF) including human papiloma virus (HPV) types associated with abnormal cervical cytology (Atypical Squamous Cells of Undetermined Significance or ASCUS) among Chilean women from low socioeconomic status in Santiago, Chile.

A random population based sample of 616 women from La Pintana (a low-income district in Santiago) participated in 2001 in a HPV prevalence study and were re-evaluated in 2006 through a risk factors questionnaire, Papanicolaou test and DNA detection for HPV. The Papanicolaou test was analyzed in Santiago and HPV analysis (PCR_GP5+/GP6+) was conducted in Vrije University, Amsterdam. Cases included 42 women with cervical lesions and controls included 574 women with normal cytology during the period 2001-2006. Logistic regression with uni and multivariate analysis was performed to identify RF for cervical lesions.

During the study period, there was a significant increase in the proportion of single women, from 8.3 to 14.8% (p < 0.05), of women with 3 or more sexual partners from 8.9 to 13.3 and of women high risk HPV, from 9.1 to 14.3%. The proportion of abnormal Papanicolaou tests remained stable (3.08 and 3.9% > ASCUS). High risk HPV was the most significant factor associated with cervical lesions (odds ratio (OR) = 9.695% > confidence intervals (CI) = 4.4-21.1) followed by oral contraceptive use (OR = 2.58 95% > CI = 1.2-5.7). Among women infected by high risk HPV, the use of oral contraceptives was a risk factor while compliance with screening was protective for cervical lesions.

From 2001 to 2006, there was an increase in the proportion of women with high-risk HPV infections.