Cervical cancer risk factors among HIV-infected Nigerian women.

BACKGROUND

Cervical cancer is the third most common cancer among women worldwide, and in Nigeria it is the second most common female cancer. Cervical cancer is an AIDS-defining cancer; however, HIV only marginally increases the risk of cervical pre-cancer and cancer. In this study, we examine the risk factors for cervical pre-cancer and cancer among HIV-positive women screened for cervical cancer at two medical institutions in Abuja, Nigeria.

METHODS

A total of 2,501 HIV-positive women participating in the cervical cancer screen-and-treat program in Abuja, Nigeria consented to this study and provided socio-demographic and clinical information. Log-binomial models were used to calculate relative risk (RR) and 95% confidence intervals (95%CI) for the risk factors of cervical pre-cancer and cancer.

RESULTS

There was a 6% prevalence of cervical pre-cancer and cancer in the study population of HIV-positive women. The risk of screening positivity or invasive cancer diagnosis reduced with increasing age, with women aged 40 years and older having the lowest risk (RR=0.4; 95%CI=0.2-0.7). Women with a CD4 count of 650 per mm3 or more also had lower risk of screening positivity or invasive cancer diagnosis (RR=0.3, 95%CI=0.2-0.6). Other factors such as having had 5 or more abortions (RR=1.8, 95%CI=1.0-3.6) and the presence of other vaginal wall abnormalities (RR=1.9, 95%CI=1.3-2.8) were associated with screening positivity or invasive cancer diagnosis.

CONCLUSION

The prevalence of screening positive lesions or cervical cancer was lower than most previous reports from Africa. HIV-positive Nigerian women were at a marginally increased risk of cervical pre-cancer and cancer. These findings highlight the need for more epidemiological studies of cervical cancer and pre-cancerous lesions among HIV-positive women in Africa and an improved understanding of incidence and risk factors.