The role of depression in sexual behaviour linked to STI and HIV transmission: a study of HIV-negative and untested gay, bisexual, and other men who have sex with men in England

HIV transmission remains ongoing among men who have sex with men (MSM). Depressive symptomatology has been linked to sexual risk-taking among sexually active MSM in the U.S. Data in Europe are lacking. The aim of this thesis was to investigate the role of depressive symptoms in sexual behaviours linked to STI/HIV transmission among gay, bisexual, and other MSM in the UK, using data from two studies. AURAH (Attitudes to, and Understanding of, Risk of Acquisition of HIV) was a cross-sectional study of HIV-negative MSM attending 20 genitourinary medicine (GUM) clinics across England (2013-2014). Men reporting recent sex were included in analysis (N=1340). PROUD was a randomized trial to assess the effectiveness of pre-exposure prophylaxis among MSM reporting condomless sex (CLS), and therefore at high-risk for HIV acquisition, in England (2012-2014, N=540 at baseline). Across studies/time-points, prevalence of depressive symptoms (PHQ-9≥10) ranged from 12.4%-14.4%; associated factors included lower socio-economic status, lower supportive network, concealment of sexuality, bisexual-identity, anti-gay attitudes, recreational drug use, and intimate partner violence. Among sexually active men in AURAH, depressive symptoms were associated with all measures of CLS, including previous sexually transmitted infection and post-exposure prophylaxis (PEP) use, even after adjusting for socio-demographics and recreational drug use (adjusted prevalence ratio for ≥2 CLS partners: 1.28 95% CI: 1.05, 1.56; p=0.013). In structural equation modelling, depression was associated with CLS indirectly via low self-efficacy (perceived inability to ensure condom-use when desired) (p