Perception of motion direction in luminance-and contrast-defined reversed-phi motion sequences

Nonlinear processing can be used to recover the motion of contrast modulations of binary noise patterns. A nonlinear stage has also been proposed to explain the perception of forward motion in motion sequences which typically elicit reversed-phi. We examined perceived direction of motion for stimuli in which these reversed motion sequences were used to modulate the contrast of binary noise patterns. A percept of forward motion could be elicted by both luminance-defined and contrast-defined stimuli. The perceived direction of motion seen in the contrast-defined stimuli showed a profound carrier dependency. The replacement of a static carrier by a dynamic carrier can reverse the perceived direction of motion. Forward motion was never seen with dynamic carriers. For luminance- and contrast-defined patterns the reversed motion percept increasingly dominated, with increases in the spatial frequency and temporal frequency of the modulation. Differences in the patterns of responses to the two stimuli over spatial and temporal frequency were abolished by the addition of noise to the luminance-defined stimulus. These data suggest the possibility that a single mechanism may mediate the perception of luminance- and contrast-defined motion

Intimate partner violence, depression, and sexual behaviour among gay, bisexual and other men who have sex with men in the PROUD trial.

BACKGROUND: Little is known about the prevalence and correlates of intimate partner violence (IPV) among gay, bisexual and other men who have sex with men (GBMSM) in the UK. The aim of this study was to investigate the prevalence of IPV, associations of socio-economic and psychosocial factors with IPV, and the association of IPV with depression and sexual behaviour, among GBMSM in the PROUD trial of pre-exposure prophylaxis (PrEP). METHODS: PROUD enrolled 544 HIV-negative participants in England from 2012 to 2014; participants were randomised to immediate or deferred PrEP. This analysis included 436 GBMSM who had IPV data at month-12 and/or 24. Prevalence of IPV victimization and perpetration (lifetime, and in the past year) was assessed at these time-points. Generalized estimating equations were used to investigate associations with IPV, using pooled data from both time-points. RESULTS: At month-12 (N = 410), 44.9% of men reported ever being a victim of IPV, 15.6% in the last year, and 19.5% reported ever perpetrating IPV, 7.8% in the last year. At month-24 (N = 333), the corresponding prevalence was 40.2 and 14.7% for lifetime and past year IPV victimization and 18.0 and 6.9% for lifetime and past year IPV perpetration. IPV prevalence did not differ by randomised arm. Men reporting internalized homophobia and sexualized drug use were more likely to report IPV. Lifetime and last year experience of IPV victimization and perpetration were strongly associated with depressive symptoms (PHQ-9 ≥ 10) (adjusted for socio-demographics: lifetime IPV victimization PR 2.57 [95% CI: 1.71, 3.86]; past year IPV victimization PR 2.93 [95% CI: 1.96, 4.40]; lifetime IPV perpetration PR 2.87 [95% CI: 1.91, 4.32]; past year IPV perpetration PR 3.47 [95% CI: 2.13, 5.64], p < 0.001 for all); IPV was not consistently associated with measures of condomless anal sex or high partner numbers. CONCLUSIONS: GBMSM at high-risk of HIV who are seeking/taking PrEP may experience a high burden of IPV, which may be linked to depression. Training on awareness of and enquiry for IPV among GBMSM in sexual health clinics is recommended. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02065986 . Registered 19 February 2014 (retrospectively registered)

“Sex without fear”: exploring the psychosocial impact of oral HIV pre-exposure prophylaxis on gay men in England

Gay, bisexual, and other men who have sex with men (GBMSM) experience a high prevalence of psychosocial health problems, such as harmful substance use and depression, as well as being disproportionately affected by HIV. HIV Pre-Exposure Prophylaxis (PrEP) may provide psychosocial benefits beyond its intended purpose of reducing HIV infection. We explore the psychosocial impact of oral PrEP use on gay men in England using qualitative data from the PROUD study. From February 2014 to January 2016, semi-structured in-depth interviews were conducted with 40 gay men and one trans woman. Participants were purposively recruited based on trial arm allocation, adherence, and sexual risk behaviours. By removing HIV risk from sex, PrEP improves users’ wellbeing by reducing HIV-related anxiety and internalised stigma and increasing HIV prevention self-efficacy, sexual pleasure, and intimacy. In turn, these psychological changes may influence behaviour in the form of greater sexual freedom, reduced harmful drug use, and more protective sexual health behaviours. However, PrEP may create internal conflict for some gay men, due to its disruption of social norms around condom use and its perceived influence on their sexual behaviour leading to reduced condom self-efficacy. These findings provide a baseline of PrEP’s psychosocial impact amongst some of the first PrEP users in England and supports calls to consider the psychosocial impact of PrEP in prescribing guidelines

Rapid testing and treatment for sexually transmitted infections improve patient care and yield public health benefits

A service evaluation of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) testing and result notification in patients attending a rapid testing service (Dean Street Express [DSE]) compared with those attending an existing ‘standard’ sexual health clinic (56 Dean Street [56DS]), and modelling the impact of the new service from 1 June 2014 to 31 May 2015. Primary outcome: time from patients’ sample collection to notification of test results at DSE compared with 56DS. Secondary outcomes estimated using a model: number of transmissions prevented and the number of new partner visits avoided and associated cost savings achieved due to rapid testing at DSE. In 2014/15, there were a total of 81,352 visits for CT/NG testing across 56DS (21,086) and DSE (60,266). Rapid testing resulted in a reduced mean time to notification of 8.68 days: 8.95 days for 56DS (95% CI 8.91–8.99) compared to 0.27 days for DSE (95% CI 0.26–0.28). Our model estimates that rapid testing at DSE would lead to 196 CT and/or NG transmissions prevented (2.5–97.5% centile range = 6–956) and lead to annual savings attributable to reduced numbers of partner attendances of £124,283 (2.5–97.5% centile range = £4260–590,331). DSE, a rapid testing service for asymptomatic infections, delivers faster time to result notification for CT and/or NG which enables faster treatment, reduces infectious periods and leads to fewer transmissions, partner attendances and clinic costs

The success of HIV combination prevention: The Dean Street model

The 56 Dean Street combination prevention model, a strong engagement with the LGBTQI community and flexible services adapted to users’ changing needs led to an 80% drop in HIV diagnoses in gay, bisexual and other men who have sex with men (GBMSM) from 2015 to 2017. We describe the service changes at 56 Dean Street since 2012 which resulted in an increase in the frequency of HIV testing, the introduction of pre-exposure prophylaxis, earlier HIV diagnosis and a shorter time to viral suppression in those living with HIV. This model could be adapted to deliver similar results in those settings of high HIV prevalence among GBMSM and where access to technological innovation in healthcare and engagement with the community can be achieved

Exposure and impact of a mass media campaign targeting sexual health amongst Scottish men who have sex with men: an outcome evaluation

Background: This paper explores the exposure and impact of a Scottish mass media campaign: Make Your Position Clear. It ran from October 2009 to July 2010, targeted gay men and other men who have sex with men (MSM), and had two key aims: to promote regular sexual health and HIV testing every 6 months, and to promote the use of appropriate condoms and water-based lubricant with each episode of anal intercourse. Methods: A cross-sectional survey (anonymous and self-report) was conducted 10 months after the campaign was launched (July 2010). Men were recruited from commercial venues. Outcome measures included use of lubricant, testing for sexually transmitted infections and HIV, and intentions to seek HIV testing within the following six months. Linear-by-linear chi-square analysis and binary logistic regressions were conducted to explore the associations between the outcome measures and campaign exposure. Results: The total sample was 822 men (62.6% response rate). Men self-identifying as HIV positive were excluded from the analysis (n = 38). Binary logistic analysis indicated that those with mid or high campaign exposure were more likely to have been tested for HIV in the previous six months when adjusted for age, area of residence and use of the “gay scene” (AOR = 1.96, 95% CI = 1.26 to 3.06, p = .003), but were not more likely to be tested for STIs (AOR = 1.37, 95% CI = 0.88 to 2.16, p = .167). When adjusted for previous HIV testing, those with mid or high campaign exposure were not more likely to indicate intention to be tested for HIV in the following six months (AOR = 1.30, 95% CI = 0.73 to 2.32, p = .367). Those with no campaign exposure were less likely than those with low exposure to have used appropriate lubricant with anal sex partners in the previous year (AOR = 0.42, 95% CI = 0.23 to 0.77, p = .005). Conclusions: The campaign had demonstrable reach. The analysis showed partial support for the role of mass media campaigns in improving sexual health outcomes. This suggests that a role for mass media campaigns remains within combination HIV prevention

Evolution of a pre-exposure prophylaxis (PrEP) service in a community-located sexual health clinic: Concise report of the PrEPxpress

Screening and treatment of sexually transmissible infections, including HIV, are free in the UK nations pre-exposure prophylaxis (PrEP) became free in England in October 2017 through the PrEP Impact trial. Doctor-led PrEP clinics started at 56 Dean Street in September 2015, with the drug purchased privately at full price. The service was expanded to other staff to support initiation and monitoring of increasing numbers of attendees purchasing PrEP from online pharmacies. Nonetheless, when the clinic was given a target of 1700 for the PrEP Impact trial, it was clear this could not be achieved in a timely manner through 56 Dean Street alone. To prepare for the trial, all staff with HIV testing competencies were trained in good clinical practice and trial-specific procedures, and a patient group directive was approved to facilitate nurse prescribing and dispensing. Electronic pro formas to capture eligibility for starting or continuing PrEP were adapted for the Dean Street Express clinic, with some information collected directly from service users using touch screens. These interventions, together with an update to the 2016 information leaflet developed by the community, enabled enrolment and follow-up of 1700 participants in 4 months. PrEP advice and monitoring were easily accommodated in the 56 Dean Street sexual health service, but did require additional training and approval for nurse prescribing and dispensing drug in order to achieve the target, which still fell short of the demand

Sexual behaviours and sexually transmitted infection outcomes in a cohort of HIV-negative men who have sex with men attending sexual health clinics in England.

Men who have sex with men (MSM) attending sexual health (SH) clinics are at high risk for HIV acquisition and are disproportionately affected by sexually transmitted infections (STIs). We collected standardised behavioural data from MSM attending clinics to characterise sexual behaviours and identify predictors for HIV and STIs. In 2012–2013, HIV-negative MSM attending five SH clinics in England reported sexual behaviours in the previous three months via a self-administered questionnaire. Behaviours were linked to the individual’s clinical records using national surveillance. The prevalence and incidence of bacterial STIs (gonorrhoea, Chlamydia, lymphogranuloma venereum and syphilis) and incidence of HIV were calculated. Adjusted odds ratios and hazard ratios with 95% confidence interval (CI) were reported for significant predictors. Of 1278 HIV-negative MSM, 54% were of white ethnicity and UK-born and 43% were 25–34 years old. Almost all men reported at least one partner in the last three months. Half reported condomless anal sex and 36% condomless receptive anal intercourse (CRAI). Incidence of bacterial STIs was 46/100 (95%CI 39–54) person years (py) and of HIV was 3.1/100 (95%CI 1.7–5.6) py. A STI at baseline and CRAI with increasing numbers of partners were associated with both incident infections. In this cohort of MSM high-risk behaviours and STIs were prevalent. Engagement in CRAI increased the likelihood of subsequent infection, while men diagnosed with a bacterial STI were at increased risk of a future STI. Clinical and behavioural risk assessments to determine an individual’s risk of infection could allow a more nuanced prevention approach that has greater success in reducing transmission

Sexual behaviours and sexually transmitted infection outcomes in a cohort of HIV-negative men who have sex with men attending sexual health clinics in England

Men who have sex with men (MSM) attending sexual health (SH) clinics are at high risk for HIV acquisition and are disproportionately affected by sexually transmitted infections (STIs). We collected standardised behavioural data from MSM attending clinics to characterise sexual behaviours and identify predictors for HIV and STIs. In 2012-2013, HIV-negative MSM attending five SH clinics in England reported sexual behaviours in the previous three months via a self-administered questionnaire. Behaviours were linked to the individual's clinical records using national surveillance. The prevalence and incidence of bacterial STIs (gonorrhoea, Chlamydia, lymphogranuloma venereum and syphilis) and incidence of HIV were calculated. Adjusted odds ratios and hazard ratios with 95% confidence interval (CI) were reported for significant predictors. Of 1278 HIV-negative MSM, 54% were of white ethnicity and UK-born and 43% were 25-34 years old. Almost all men reported at least one partner in the last three months. Half reported condomless anal sex and 36% condomless receptive anal intercourse (CRAI). Incidence of bacterial STIs was 46/100 (95%CI 39-54) person years (py) and of HIV was 3.1/100 (95%CI 1.7-5.6) py. A STI at baseline and CRAI with increasing numbers of partners were associated with both incident infections. In this cohort of MSM high-risk behaviours and STIs were prevalent. Engagement in CRAI increased the likelihood of subsequent infection, while men diagnosed with a bacterial STI were at increased risk of a future STI. Clinical and behavioural risk assessments to determine an individual's risk of infection could allow a more nuanced prevention approach that has greater success in reducing transmission

“Sex without fear”: exploring the psychosocial impact of oral HIV pre-exposure prophylaxis on gay men in England

Gay, bisexual, and other men who have sex with men (GBMSM) experience a high prevalence of psychosocial health problems, such as harmful substance use and depression, as well as being disproportionately affected by HIV. HIV Pre-Exposure Prophylaxis (PrEP) may provide psychosocial benefits beyond its intended purpose of reducing HIV infection. We explore the psychosocial impact of oral PrEP use on gay men in England using qualitative data from the PROUD study. From February 2014 to January 2016, semi-structured in-depth interviews were conducted with 40 gay men and one trans woman. Participants were purposively recruited based on trial arm allocation, adherence, and sexual risk behaviours. By removing HIV risk from sex, PrEP improves users’ wellbeing by reducing HIV-related anxiety and internalised stigma and increasing HIV prevention self-efficacy, sexual pleasure, and intimacy. In turn, these psychological changes may influence behaviour in the form of greater sexual freedom, reduced harmful drug use, and more protective sexual health behaviours. However, PrEP may create internal conflict for some gay men, due to its disruption of social norms around condom use and its perceived influence on their sexual behaviour leading to reduced condom self-efficacy. These findings provide a baseline of PrEP’s psychosocial impact amongst some of the first PrEP users in England and supports calls to consider the psychosocial impact of PrEP in prescribing guidelines