Intimate partner violence a major contributor to HIV epidemic among MSM in China, shows study

HIV prevention programmes targeted at men who have sex with men (MSM) should include intimate partner violence (IPV) screening and interventions, research published in Nature Scientific Reports shows. Investigators from China found that recent experience of IPV was associated with a fourfold increase in the risk of infection with HIV. Moreover, experiencing IPV was a more important risk factor for infection with HIV than several other factors traditionally associated with high HIV risk, with 38% of the risk attributed to IPV.

“Our results suggest that being a victim of IPV was an independent determinant of HIV seroconversion among MSM in China,” comment the investigators. “If we want to control the spread of the HIV epidemic among MSM by adopting a comprehensive intervention strategy, this intervention must address IPV factors in male-to-male relationships.”

The HIV epidemic among MSM in China is expanding rapidly. The proportion of new HIV diagnoses in the country attributed to sex between men more than doubled between 2006 and 2017, from 12% to 26%.

Glossary

condomless

Having sex without condoms, which used to be called ‘unprotected’ or ‘unsafe’ sex. However, it is now recognised that PrEP and U=U are effective HIV prevention tools, without condoms being required. Nonethless, PrEP and U=U do not protect against other STIs. 

person years

In a study “100 person years of follow-up” could mean that information was collected on 100 people for one year, or on 50 people for two years each, or on ten people over ten years. In practice, each person’s duration of follow-up is likely to be different.

receptive

Receptive anal intercourse refers to the act of being penetrated during anal intercourse. The receptive partner is the ‘bottom’.

traditional risk factors

Risk factors for a disease which are well established from studies in the general population. For example, traditional risk factors for heart disease include older age, smoking, high blood pressure, cholesterol and diabetes. ‘Traditional’ risk factors may be contrasted with novel or HIV-related risk factors.

depression

A mental health problem causing long-lasting low mood that interferes with everyday life.

IPV is highly prevalent in many communities and has been associated with increased HIV risk. However, virtually nothing is known about the prevalence of IPV among MSM and its relationship with the HIV epidemic.

Investigators, therefore, designed a prospective study involving 476 HIV-negative MSM in Shenyang, China who were followed for 12 months. Their aims were to establish the prevalence of IPV, the association between IPV and recent infection and the proportion of HIV infection risk (population attributable fraction – PAF) attributable to IPV.

The study population was young, with a median age of 28 years. Two-fifths had a college education and 64% were single. Approximately 40% reported multiple male sex partners, a fifth had condomless anal sex with casual partners and 22% reported receptive condomless anal sex with casual partners in the previous three months. At baseline, 12% of men had syphilis. Depression was present in 37% of people.

In the three months before enrollment, 19% of men experienced IPV. When broken down by type, 10% had experienced physical IPV, 14% psychological IPV and 10% sexual IPV.

Factors associated with IPV were lower levels of education, condomless anal sex and depression (all p < 0.05).

There were 16 new HIV infections during 300 person-years of follow-up, an overall incidence of 5.3 per 100 person-years. Incidence was much higher among individuals reporting IPV compared to individuals who did not experience IPV (11.3 vs 3.8 per 100 person-years).

After taking into account age, education, income level and marital status, the investigators found that, compared to those who did not experience IPV, victims of IPV were significantly more likely to have had seroconverted for HIV (aHR = 4.1; 95% CI, 1.5-11.6) and the PAF associated with IPV was 38%. IPV was a more important factor in recent HIV infections than numerous traditional risk factors, such as receptive condomless anal sex with a casual partner (aHR = 3.1; 95% CI, 1.1-9.3; PAF = 24%).

“A total of 37.9% of incident HIV infection could be attributed to recent IPV victimization, which is higher than the corresponding value estimated in heterosexual women from high prevalence areas of both HIV and IPV (South Africa: PAF = 11.9%; Uganda: PAF = 22.2%),” note the authors. “This implies that interventions aimed at effectively controlling violence in the MSM population would achieve a better reduction in the incidence of HIV than in heterosexual populations.”

They conclude, “HIV prevention strategies need to be more sophisticated and should incorporate IPV screening followed by effective intervention. In the subgroup of MSM affected by IPV, it is also essential to pursue bio-medical prevention (including PrEP [pre-exposure prophylaxis]) in order to reduce their risk of acquiring HIV. It should be a priority to establish and improve the support services for IPV victims and to give them advice on how to terminate an unhealthy, potentially life-threatening relationship.”

References

Wang H-Y et al. Intimate partner violence correlates with a higher HIV incidence among MSM: a 12-month prospective cohort study in Shenyang, China. Nature Scientific Reports, 8: 2879. DOI: 1038/s41598-018-21149-8 (2018).