South African women in abusive relationships may be at increased risk for HIV

More than 10% of new HIV infections among women in rural South Africa may have been prevented if the women were not in an abusive relationship, according to recent study results.

Researchers conducted a longitudinal analysis of data from a previously published cluster-randomized controlled trial undertaken in the Eastern Cape province in South Africa from 2002 to 2006. The initial trial consisted of a 50-hour educational program about sexual and reproductive health and HIV conducted during a 6-week period. There were 1,099 volunteers aged 16 to 23 years recruited from local schools and screened for HIV at enrollment and then at 12 and 24 months after the program was completed.

The current study was an analysis of these data. The aim was to evaluate the effects of intimate partner violence and power inequality in relationships on incidence of HIV infection.

Baseline information collected from the volunteers included age, completed years of schooling, socioeconomic status, number of sexual partners, number of pregnancies, frequency of condom use and time since first sexual intercourse. Most women were in school with 2 or more years left until completion and came from poor or very poor households. Condom use was reported by 517 sexually active women; all participants were unmarried, and 197 were mothers.

Results indicated that 11.9% of new HIV infections in women could have been prevented if they did not experience more than one episode of physical or sexual violence. If no women were in relationships in which they had low power, 13.9% of incident HIV could have been avoided.

The researchers measured power within sexual relationships by proposing the following scenario: “When someone wants me to sleep over he expects me to agree.” The answers were assessed on a four-point Likert scale. Women in the lowest tertile of power were compared with those in the middle and upper tertiles. Intimate partner violence was measured by using the WHO’s nine-item instrument.

There were 41 women who had not had sexual intercourse at the 12-month mark and 18 women who had not had sex at 24 months, according to the results.

There were 128 new HIV infections during 2,076 person-years of follow-up, for an incidence rate of 6.2 per 100 person-years. Among 325 women with low relationship power at baseline, 51 acquired HIV during follow-up, for a rate of 8.5 infections per 100 person-years. By contrast, 73 of 704 women with medium or high relationship equity acquired HIV (5.5 per 100 person-years). Multivariate analysis results indicated that the Poisson model incidence rate ratio of HIV infection in women with low power compared with those with medium or high power was 1.51 (95% CI, 1.05-2.17).

Among 253 women who reported more than one episode of intimate partner violence at baseline, 45 acquired HIV during follow-up (9.6 per 100 person-years). By comparison, among 846 women with one or no episodes of violence, 83 acquired HIV (5.2 per 100 person-years). The Poisson incidence rate ratio for this comparison was also 1.51 (1.04-2.21).

Jewkes RK. Lancet. 2010;doi:10.1016/S0140-6736(10)60548-X.