OBJECTIVES: Cervical cancer screening by visual inspection with acetic acid (VIA) is a widely used alternative to cytology in developing countries. This study aimed to evaluate risk factors associated with a positive VIA test and with cervical high-grade lesions on cytology.

METHODS: We conducted a large cross-sectional study among 3339 women from urban and rural Tanzania. Study participants were interviewed about socio-demographic, reproductive and lifestyle factors. Blood samples were tested for HIV, and a gynaecological examination was performed. Human papillomavirus (HPV) status was determined by Hybrid Capture 2, and HPV genotyping was done using the LiPA Extra test. We used multivariable logistic regression to estimate adjusted odds ratios (ORs) and confidence intervals (CIs).

RESULTS: The strongest risk factors for VIA positivity were positivity to HIV (OR = 3.48; 95% CI: 2.34-5.17) or to high-risk HPV (HrHPV) (OR = 1.97; 95% CI: 1.37-2.85). HrHPV was by far the strongest predictor of high-grade cytology (OR = 110.1; 95% CI: 50.4-240.4), while there was no significant association with HIV in the multivariable analysis (OR = 1.27; 95% CI: 0.78-2.08). After adjustment for HrHPV, HIV and age, the risk of high-grade cytology also increased with increasing age, number of births and low body mass index (BMI), while high BMI decreased the risk of VIA positivity.

CONCLUSIONS: Infection with HrHPV is a major risk factor for high-grade cytology, while VIA positivity is associated with HIV and to a lesser extent with HrHPV.