Examining the secondary impacts of the COVID-19 pandemic on syndemic production and PrEP use among gay, bisexual and other men who have sex with men (GBM) in Vancouver, Canada.

BACKGROUND: The secondary impacts of the COVID-19 pandemic may disproportionately affect gay, bisexual, and other men who have sex with men (GBM), particularly related to HIV prevention and treatment outcomes. We applied syndemic theory to examine PrEP disruptions during the during the height of the COVID-19 pandemic in Vancouver, Canada. METHODS: Sexually-active GBM, aged 16 + years, were enrolled through respondent-driven sampling (RDS) from February 2017 to August 2019. Participants completed a Computer-Assisted Self-Interview every six months and data were linked to the BC PrEP Program (program responsible for publicly funded PrEP in the province) to directly measure PrEP disruptions. The analysis period for this study was from March 2018-April 2021. We used univariable generalized linear mixed models to examine (1) six-month trends for syndemic conditions: the prevalence of moderate/severe depressive or anxiety symptoms, polysubstance use, harmful alcohol consumption, intimate partner violence, and (2) six-month trends for PrEP interruptions among HIV-negative/unknown GBM. We also applied 3-level mixed-effects logistic regression with RDS clustering to examine whether syndemic factors were associated with PrEP interruptions. RESULTS: Our study included 766 participants, with 593 participants who had at least one follow-up visit. The proportion of respondents with abnormal depressive symptoms increased over the study period (OR = 1.35; 95%CI = 1.17, 1.56), but we found decreased prevalence for polysubstance use (OR = 0.89; 95%CI = 0.82, 0.97) and binge drinking (OR = 0.74; 95%CI = 0.67, 0.81). We also found an increase in PrEP interruptions (OR = 2.33; 95%CI = 1.85, 2.94). GBM with moderate/severe depressive symptoms had higher odds (aOR = 4.80; 95%CI = 1.43, 16.16) of PrEP interruptions, while GBM with experiences of IPV had lower odds (aOR = 0.38; 95%CI = 0.15, 0.95) of PrEP interruptions. GBM who met clinical eligibility for PrEP had lower odds of experiencing PrEP interruptions (aOR = 0.25; 95%CI = 0.11, 0.60). CONCLUSION: There were increasing PrEP interruptions since March 2020. However, those most at risk for HIV were less likely to have interruptions. Additional mental health services and targeted follow-up for PrEP continuation may help to mitigate the impacts of the COVID-19 pandemic on GBM.

Use of Gay Chatlines and Online Dating Platforms as Potential Mediators or Moderators in the Relationship Between Loneliness, Self-Rated Attractiveness and Human Immunodeficiency Virus Acquisition Risk Among Gay, Bisexual, and Other Men Who Have Sex With Men in Vancouver, Canada.

BACKGROUND: Gay, bisexual, and other men who have sex with men (gbMSM) remain disproportionately affected by human immunodeficiency virus (HIV). Interaction between psychosocial factors likely plays a role in HIV acquisition risk. We aimed to analyze the association of loneliness and self-rated attractiveness with HIV acquisition risk, and determine whether these associations were mediated by gay telephone chatlines or online dating platforms. METHODS: This cross-sectional study included HIV-negative gbMSM 16 years or older enrolled into the Momentum Health Study from February 2012 to February 2015. Loneliness, self-rated attractiveness (exposures) and use of gay chatlines or online dating platforms (mediators) were assessed through self-interviews. Human immunodeficiency virus acquisition risk (outcome) was assessed by the HIV Incidence Risk Index. Weighted logistic regression modeled the association and moderation effect between exposures and outcome. Mediation models estimated 3-way direct effect among exposures, mediators, and outcome. RESULTS: Of 542 gbMSM, those who were lonely (adjusted odds ratio [aOR], 1.54; 95% confidence intervals [CI], 1.04-2.28) and attractive (aOR, 1.69; 95% CI, 1.04-2.76) had increased odds for HIV acquisition risk. Our moderation analysis demonstrated a heightened joint effect among lonely and attractive participants (aOR, 1.70; 95% CI, 1.08-2.65). Use of gay telephone chatlines or online dating platforms mediated 30.5% of the association between loneliness and HIV acquisition risk, but did not mediate attractiveness and HIV acquisition risk. CONCLUSIONS: Our findings suggest that the provision of interventions focusing on mental health support and safer sex practices through gay telephone chatlines or online dating platforms is promising to help alleviate the HIV burden among gbMSM.

Digital signature schemes with strong existential unforgeability.

Digital signature schemes (DSS) are ubiquitously used for public authentication in the infrastructure of the internet, in addition to their use as a cryptographic tool to construct even more sophisticated schemes such as those that are identity-based. The security of DSS is analyzed through the existential unforgeability under chosen message attack (EUF-CMA) experiment which promises unforgeability of signatures on new messages even when the attacker has access to an arbitrary set of messages and their corresponding signatures. However, the EUF-CMA model does not account for attacks such as an attacker forging a different signature on an existing message, even though the attack could be devastating in the real world and constitutes a severe breach of the security system. Nonetheless, most of the DSS are not analyzed in this security model, which possibly makes them vulnerable to such an attack. In contrast, a better security notion known as strong EUF-CMA (sEUF-CMA) is designed to be resistant to such attacks. This review aims to identify DSS in the literature that are secure in the sEUF-CMA model. In addition, the article discusses the challenges and future directions of DSS. In our review, we consider the security of existing DSS that fit our criterion in the sEUF-CMA model; our criterion is simple as we only require the DSS to be at least secure against the minimum of existential forgery. Our findings are categorized into two classes: the direct and indirect classes of sEUF-CMA. The former is inherently sEUF-CMA without any modification while the latter requires some transformation. Our comprehensive  review contributes to the security and cryptographic research community by discussing the efficiency and security of DSS that are sEUF-CMA, which aids in selecting robust DSS in future design considerations.

How Does the Location of Transfer Affect Travellers and Their Choice of Travel Mode?-A Smart Spatial Analysis Approach.

This study explores the relationship between the spatial distribution of relative transfer location (i.e., the location of the transfer point in relation to the trip origin and destination points) and the attractiveness of the transit service using smart card data. Transfer is an essential component of the transit trip that allows people to reach more destinations, but it is also the main factor that deters the smartness of the public transit. The literature quantifies the inconvenience of transfer in terms of extra travel time or cost incurred during transfer. Unlike this conventional approach, the new "transfer location" variable is formulated by mapping the spatial distribution of relative transfer locations on a homogeneous geocoordinate system. The clustering of transfer points is then quantified using grid-based hierarchical clustering. The transfer location factor is formulated as a new explanatory variable for mode choice modelling. This new variable is found to be statistically significant, and no correlation is observed with other explanatory variables, including transit travel time. These results imply that smart transit users may perceive the travel direction (to transfer) as important, in addition to the travel time factor, which would influence their mode choice. Travellers may disfavour even adjacent transfer locations depending on their relative location. The findings of this study will contribute to improving the understanding of transit user behaviour and impact of the smartness of transfer, assist smart transport planning and designing of new transit routes and services to enhance the transfer performance.

Physicians' patient base composition and mortality among people living with HIV who initiated antiretroviral therapy in a universal care setting.

OBJECTIVES: To assess the impact of physicians' patient base composition on all-cause mortality among people living with HIV (PLHIV) who initiated highly active antiretroviral therapy (HAART) in British Columbia (BC), Canada. DESIGN: Observational cohort study from 1 January 2000 to 31 December 2013. SETTING: BC Centre for Excellence in HIV/AIDS' (BC-CfE) Drug Treatment Program, where HAART is available at no cost. PARTICIPANTS: PLHIV aged ≥ 19 who initiated HAART in BC in the HAART Observational Medical Evaluation and Research (HOMER) Study. OUTCOME MEASURES: All-cause mortality as determined through monthly linkages to the BC Vital Statistics Agency. STATISTICAL ANALYSIS: We examined the relationships between patient characteristics, physicians' patient base composition, the location of the practice, and physicians' experience with PLHIV and all-cause mortality using unadjusted and adjusted Cox proportional hazards models. RESULTS: A total of 4 445 PLHIV (median age = 42, Q1, Q3 = 34-49; 80% male) were eligible for our study. Patients were seen by 683 prescribing physicians with a median experience of 77 previously treated PLHIV in the past 2 years (Q1, Q3 = 23-170). A multivariable Cox model indicated that the following factors were associated with all-cause mortality: age (aHR = 1.05 per 1-year increase, 95% CI = 1.04 to 1.06), year of HAART initiation (2004-2007: aHR = 0.65, 95% CI = 0.53 to 0.81, 2008-2011: aHR = 0.46, 95% CI = 0.35 to 0.61, Ref: 2000-2003), CD4 cell count at baseline (aHR = 0.88 per 100-unit increase in cells/mm3, 95% CI = 0.82 to 0.94), and < 95% adherence in first year on HAART (aHR = 2.28, 95% CI = 1.88 to 2.76). In addition, physicians' patient base composition, specifically, the proportion of patients who have a history of injection drug use (aHR = 1.11 per 10% increase in the proportion of patients, 95% CI = 1.07 to 1.15) or Indigenous ancestry (aHR = 1.07 per 10% increase , 95% CI = 1.03-1.11) and being a patient of a physician who primarily serves individuals outside of the Vancouver Coastal Health Authority region (aHR = 1.22, 95% CI = 1.01 to 1.47) were associated with mortality. CONCLUSIONS: Our findings suggest that physicians with a higher proportion of individuals who face potential barriers to care may need additional supports to decrease mortality among their patients. Future research is required to examine these relationships in other settings and to determine strategies that may mitigate the associations between the composition of physicians' patient bases and survival.

Factors associated with delayed and late ART initiation among people living with HIV in BC: results from the engage study.

We examined correlates of late and delayed initiation of antiretroviral therapy (ART) in British Columbia, Canada. From December 2013 to December 2015 we recruited treatment-naïve people living with HIV who initiated ART within the previous year. 'Late initiation' was defined as CD4 cell count ≤500 cells/µL at ART initiation and 'delayed initiation' as ≥1 year between HIV diagnosis and initiation. Multivariable logistic regression assessed independent correlates of late and delayed initiation. Of 87 participants, 44 (51%) initiated late and 22 (26%) delayed initiation. Delayed initiation was positively associated with older age (adjusted odds ratio [AOR]: 1.06 per year, 95% confidence interval [95% CI]: 1.01-1.12) and inversely associated with wanting to start ART at diagnosis (AOR: 0.06, 95% CI: 0.02-0.21). Variables associated with late initiation were older age (AOR: 1.09 per year, 95% CI: 1.03-1.15) and medical reason(s) for initiation (AOR: 5.00, 95% CI: 1.41-17.86). Late initiation was less likely among those with greater perceived ART efficacy (AOR 0.94, 95% CI: 0.90-0.98) and history of incarceration (AOR: 0.12, 95% CI: 0.03-0.56). Disparities in timing of initiation were observed for age, perceived ART efficacy, and history of incarceration. Enhanced health services that address these factors may facilitate earlier treatment initiation.

Viral suppression and viral rebound among young adults living with HIV in Canada.

Describe the prevalence and covariates of viral suppression and subsequent rebound among younger (≤29 years old) compared with older adults.A retrospective clinical cohort study; eligibility criteria: documented HIV infection; resident of Canada; 18 years and over; first antiretroviral regimen comprised of at least 3 individual agents on or after January 1, 2000.Viral suppression and rebound were defined by at least 2 consecutive viral load measurements <50 or >50 HIV-1 RNA copies/mL, respectively, at least 30 days apart, in a 1-year period. Time to suppression and rebound were measured using the Kaplan-Meier method and Life Table estimates. Accelerated failure time models were used to determine factors independently associated with suppression and rebound.Younger adults experienced lower prevalence of viral suppression and shorter time to viral rebound compared with older adults. For younger adults, viral suppression was associated with being male and later era of combination antiretroviral initiation (cART) initiation. Viral rebound was associated with a history of injection drug use, Indigenous ancestry, baseline CD4 cell count >200, and initiating cART with a protease inhibitor (PI) containing regimen.The influence of age on viral suppression and rebound was modest for this cohort. Our analysis revealed that key covariates of viral suppression and rebound for young adults in Canada are similar to those of known importance to older adults. Women, people who use injection drugs, and people with Indigenous ancestry could be targeted by future health interventions.

Innovative Multimodal Training Program for Family Physicians Leads to Positive Outcomes Among Their HIV-Positive Patients.

CME programs can increase physicians' uptake and adherence to clinical guidelines for chronic diseases. We developed an intensive multimodal training program for family physicians to increase their competency in the management and treatment of HIV, through group learning and via close interactions with expert clinicians in HIV. We trained 51 physicians from September 2010 to June 2015 and compared their adherence to clinical guidelines 1 year before and 1 year after the program. We observed significant increases in the physicians' HIV-related clinical competencies, in accordance with clinical guidelines, and an increase in the number of HIV-positive patients seen by these physicians and the number of combination antiretroviral therapies prescribed by these physicians. By combining various pedagogical approaches, as well as creating and encouraging communities of practice, we were able to make a durable impact on physician performance and patient-specific outcomes.

Gender differences in prevalence and correlates of high sexual self-efficacy among adolescents in Soweto, South Africa: implications for gender-sensitive research and programming.

Sexual self-efficacy (SSE) - one's confidence in their ability to perform given sexual behaviours, has been shown to predict adolescents' HIV-prevention practices (e.g., Condom use). Few studies within sub-Saharan Africa, where HIV incidence and prevalence disproportionately affects young women, have examined gendered differences in SSE. We used multivariable logistic regression to identify correlates of high-SSE separately among adolescent men and women (aged 14-19) in Soweto, South Africa using a previously validated SSE scale (high-SSE [>3/6 items]; study-alpha = 0.75). SSE scale items assessed self-efficacy related to sexual refusal and condom use. Adolescent women were significantly more likely to report high-SSE than adolescent men (72.3% versus 49.5%; p < 0.01). High-SSE among adolescent men was associated with more positive beliefs about sexual relationships and negatively associated with probable depression. High-SSE among adolescent women was associated with increased HIV knowledge, more positive beliefs about condom use and sexual relationships, having an adult in the home, and negatively associated with being an older adolescent (16-17 versus ≤15), and ever experiencing physical violence. Differences in prevalence and correlates of SSE among adolescent men and women in South Africa highlight important areas for gender-sensitive interventions. Targeted efforts to reduce negative sexual beliefs, improve HIV knowledge and mental well-being may improve SSE and thus the uptake of HIV-prevention practices among adolescent men. For adolescent women, findings indicate programming should move beyond individual-levels determinants of behaviour to focus on improving enabling environments (e.g., Reduced violence and improved family relationships) in which sexual agency can be enacted.

Gender, Sexual Self-Efficacy and Consistent Condom Use Among Adolescents Living in the HIV Hyper-Endemic Setting of Soweto, South Africa.

Within HIV-endemic settings, few studies have examined gendered associations between sexual self-efficacy (SSE), one's confidence or perceived control over sexual behavior, and uptake of HIV prevention behaviors. Using cross-sectional survey data from 417 sexually-experienced adolescents (aged 14-19, median age = 18, 60% female) in Soweto, South Africa, we measured SSE using a 6-item scale (range:0-6) with 'high-SSE' = score > 3 (study alpha = 0.75). Gender-stratified logistic regression models assessed associations between high-SSE and lifetime consistent condom use. A higher proportion of women reported high-SSE (68.7%) than men (49.5%, p < 0.001). We observed no difference in reported consistent condom use by gender (45.5% among women, 45.8% among men; p = 0.943). In confounder models, high-SSE was associated with consistent condom use among men (aOR = 3.51, 95%CI = 1.86-6.64), but not women (aOR = 1.43, 95%CI = 0.74-2.77). Findings highlight that individual-level psychosocial factors are insufficient for understanding condom use and must be considered alongside the relational, social, and structural environments within which young women navigate their sexual lives.

Incidence of diabetes mellitus and factors associated with its development in HIV-positive patients over the age of 50.

OBJECTIVE: We sought to determine the incidence and factors associated with development of diabetes mellitus (DM) in older HIV-infected individuals. RESEARCH DESIGN AND METHODS: We analyzed data from people living with HIV (PLWH) ≥50 years of age enrolled in a large urban HIV outpatient clinic in Vancouver, British Columbia. Patients were categorized as having DM if they had random blood sugar ≥11.1 mmol/L, fasting blood sugar ≥7 mmol/L, HbA1C ≥6.5%, antidiabetic medication use during the follow-up period, or medical chart review confirming diagnosis of DM. We estimated the probability of developing DM, adjusting for demographic and clinical factors, using a logistic regression model. RESULTS: Among 1065 PLWH followed for a median of 13 years (25th and 75th percentile (Q1-Q3): 9-18), the incidence of DM was 1.61/100 person-years follow-up. In the analysis of factors associated with new-onset DM (n=703), 88% were male, 38% had a history of injection drug use, 43% were hepatitis C coinfected, and median body mass index was 24 kg/m2 (Q1-Q3: 21-27). Median age at antiretroviral therapy (ART) initiation was 48 years (Q1-Q3: 43-53) and at DM diagnosis was 55 years (Q1-Q3: 50-61). Patients who started ART in 1997-1999 and had a longer exposure to older ART were at the highest risk of developing DM. CONCLUSIONS: Among PLWH aged ≥50 years, the incidence of DM was 1.39 times higher than men in the general Canadian population of similar age. ART initiated in the early years of the epidemic and exposure to older ART appeared to be the main drivers of the development of DM.

Hepatitis C co-infection is associated with an increased risk of incident chronic kidney disease in HIV-infected patients initiating combination antiretroviral therapy.

BACKGROUND: Combination antiretroviral therapy (cART) has reduced mortality from AIDS-related illnesses and chronic comorbidities have become prevalent among HIV-infected patients. We examined the association between hepatitis C virus (HCV) co-infection and chronic kidney disease (CKD) among patients initiating modern antiretroviral therapy. METHODS: Data were obtained from the Canadian HIV Observational Cohort for individuals initiating cART from 2000 to 2012. Incident CKD was defined as two consecutive serum creatinine-based estimated glomerular filtration (eGFR) measurements <60 mL/min/1.73m2 obtained ≥3 months apart. CKD incidence rates after cART initiation were compared between HCV co-infected and HIV mono-infected patients. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox regression. RESULTS: We included 2595 HIV-infected patients with eGFR >60 mL/min/1.73m2 at cART initiation, of which 19% were HCV co-infected. One hundred and fifty patients developed CKD during 10,903 person-years of follow-up (PYFU). The CKD incidence rate was higher among co-infected than HIV mono-infected patients (26.0 per 1000 PYFU vs. 10.7 per 1000 PYFU). After adjusting for demographics, virologic parameters and traditional CKD risk factors, HCV co-infection was associated with a significantly shorter time to incident CKD (HR 1.97; 95% CI: 1.33, 2.90). Additional factors associated with incident CKD were female sex, increasing age after 40 years, lower baseline eGFR below 100 mL/min/1.73m2, increasing HIV viral load and cumulative exposure to tenofovir and lopinavir. CONCLUSIONS: HCV co-infection was associated with an increased risk of incident CKD among HIV-infected patients initiating cART. HCV-HIV co-infected patients should be monitored for kidney disease and may benefit from available HCV treatments.

Conspiracy beliefs and knowledge about HIV origins among adolescents in Soweto, South Africa.

PURPOSE: We examined adolescents' knowledge regarding the origin of HIV/AIDS and correlates of beliefs surrounding conspiracy theories in Soweto, South Africa. Now, a decade post-AIDS denialism, South Africa has the largest antiretroviral therapy roll-out worldwide. However, conspiracy theories stemming from past AIDS denialism may impact HIV prevention and treatment efforts. METHODS: Study participants were recruited through the Kganya Motsha Adolescent Health Centre and the Perinatal HIV Research Unit's Botsha Bophelo Adolescent Health Study (BBAHS). Adolescents were eligible to participate if aged 14-19 years and living in Soweto. We calculated the proportion of adolescents who correctly believed that HIV originated from non-human primates, and used contingency table analysis and logistic regression modeling to describe correlates associated with accurate knowledge and beliefs in conspiracy theories. RESULTS: Of 830 adolescents, 168 (20.2%) participants correctly identified HIV as originating from chimpanzees and one third (n = 71, 8.6%) believed in a conspiracy theory about the origins of HIV, including that it originated from the US government (2.3%), the pharmaceutical industry (2.2%), a vaccine (2.1%), space (1.5%), and a scientist (0.6%). Participants who were more likely to correctly identify the origin of HIV were older, men, and unemployed. Participants who were men, unemployed or students, and who had a parent or close relative who had died of HIV, were more likely to believe in a conspiracy theory regarding the origins of HIV. CONCLUSIONS: Adolescents living in Soweto did not have high levels of accurate knowledge regarding the origins of HIV/AIDS and conspiracy beliefs were present among a small minority of participants. Accurate knowledge of the origins of HIV and debunking myths are important for improving uptake of HIV prevention tools in this population.

The Botsha Bophelo Adolescent Health Study: A profile of adolescents in Soweto, South Africa.

BACKGROUND: Youth between the ages of 15 years to 24 years account for almost half of new HIV infections in South Africa. OBJECTIVES: To describe the study details of the Botsha Bophelo Adolescent Health Study (BBAHS) which was an investigation of HIV risk among adolescents living in Soweto, South Africa. METHODS: Eligibility criteria for the BBAHS included being 14 years - 19 years old and living in one of the 41 identified formal and informal areas in the township of Soweto. A cross-sectional survey was developed between investigators and an adolescent community advisory board consisting of previously validated scales and original questions including demographics, sexual and reproductive health, health service utilisation and psychosocial behaviours. RESULTS: Between 2010 and 2012, interviewers administered surveys among 830 adolescents (57% females), whose median age was 17 years (Q1, Q3: 16, 18), and found that 43% of participants identified their ethnicity as Zulu, 52% reported high food insecurity, 37% reported at least one parent had died, 15% reported living in a shack and 83% identified as heterosexual. Over half of the participants (55%) reported ever having sex (49% of females and 64% of males), 11% of whom initiated sex at < 15 years of age (3% females and 21% males). Almost half (47%) reported ever testing for HIV, 3% (n = 12) of whom self-reported being HIV-positive and 33% (n = 4) were on antiretroviral therapy. CONCLUSION: Our study highlights important individual, relational and structural level determinants of HIV risk for adolescent men and women growing up within HIV hyperendemic settings.

Prevalence, type, and correlates of trauma exposure among adolescent men and women in Soweto, South Africa: implications for HIV prevention.

BACKGROUND: Youth trauma exposure is associated with syndemic HIV risk. We measured lifetime prevalence, type, and correlates of trauma experience by gender among adolescents living in the HIV hyper-endemic setting of Soweto, South Africa. METHODS: Using data from the Botsha Bophelo Adolescent Health Survey (BBAHS), prevalence of "ever" experiencing a traumatic event among adolescents (aged 14-19) was assessed using a modified Traumatic Event Screening Inventory-Child (TESI-C) scale (19 items, study alpha = 0.63). We assessed self-reported number of potentially traumatic events (PTEs) experienced overall and by gender. Gender-stratified multivariable logistic regression models assessed independent correlates of 'high PTE score' (≥7 PTEs). RESULTS: Overall, 767/830 (92%) participants were included (58% adolescent women). Nearly all (99.7%) reported experiencing at least one PTE. Median PTE was 7 [Q1,Q3: 5-9], with no gender differences (p = 0.19). Adolescent men reported more violent PTEs (e.g., "seen an act of violence in the community") whereas women reported more non-violent HIV/AIDS-related PTEs (e.g., "family member or someone close died of HIV/AIDS"). High PTE score was independently associated with high food insecurity among adolescent men and women (aOR = 2.63, 95%CI = 1.36-5.09; aOR = 2.57, 95%CI = 1.55-4.26, respectively). For men, high PTE score was also associated with older age (aOR = 1.40/year, 95%CI = 1.21-1.63); and recently moving to Soweto (aOR = 2.78, 95%CI = 1.14-6.76). Among women, high PTE score was associated with depression using the CES-D scale (aOR = 2.00, 95%CI = 1.31-3.03,) and inconsistent condom use vs. no sexual experience (aOR = 2.69, 95%CI = 1.66-4.37). CONCLUSION: Nearly all adolescents in this study experienced trauma, with gendered differences in PTE types and correlates, but not prevalence. Exposure to PTEs were distributed along social and gendered axes. Among adolescent women, associations with depression and inconsistent condom use suggest pathways for HIV risk. HIV prevention interventions targeting adolescents must address the syndemics of trauma and HIV through the scale-up of gender-transformative, youth-centred, trauma-informed integrated HIV and mental health services.

Predictors of viral suppression and rebound among HIV-positive men who have sex with men in a large multi-site Canadian cohort.

BACKGROUND: Gay, bisexual and other men who have sex with men (MSM) are disproportionately affected by HIV in Canada. Combination antiretroviral therapy has been shown to dramatically decrease progression to AIDS, premature death and HIV transmission. However, there are no comprehensive data regarding combination antiretroviral therapy outcomes among this population. We sought to identify socio-demographic and clinical correlates of viral suppression and rebound. METHODS: Our analysis included MSM participants in the Canadian Observational Cohort, a multi-site cohort of HIV-positive adults from Canada's three most populous provinces, aged ≥18 years who first initiated combination antiretroviral therapy between 2000 and 2011. We used accelerated failure time models to identify factors predicting time to suppression (2 measures <50 copies/mL ≥30 days apart) and subsequent rebound (2 measures >200 copies/mL ≥30 days apart). RESULTS: Of 2,858 participants, 2,448 (86 %) achieved viral suppression in a median time of 5 months (Q1-Q3: 3-7 months). Viral suppression was significantly associated with later calendar year of antiretroviral therapy initiation, no history of injection drug use, lower baseline viral load, being on an initial regimen consisting of non-nucleoside reverse-transcriptase inhibitors, and older age. Among those who suppressed, 295 (12 %) experienced viral rebound. This was associated with earlier calendar year of antiretroviral therapy initiation, injection drug use history, younger age, higher baseline CD4 cell count, and living in British Columbia. CONCLUSIONS: Further strategies are required to optimize combination antiretroviral therapy outcomes in men who have sex with men in Canada, specifically targeting younger MSM and those with a history of injection drug use.

Medical care delivery at the Inaugural Youth Olympic Games Singapore 2010.

CONTEXT: Mass gatherings such as the Youth Olympic Games require medical services for large populations with special needs specific to elite competitive youth athletes. The location of the Games in a heavily populated city with dispersed competition venues provides unique challenges. OBJECTIVE: To describe the planning and delivery of medical services and to provide data for future planning. SETTING: Singapore. One large multipurpose clinic was set up in the Games Village as well as medical posts at competitive venues for 26 sports for onsite coverage. PERIOD OF COVERAGE: 10 August 2010 to 28 August 2010. Participants A total of 1,337 medical encounters ranging from athletes to officials and volunteers who received medical care from a spectrum of medical professionals. MAJOR OUTCOME MEASURES: measures Number of cases attended to at the Games Village medical centres and the medical posts at the competition venues, utilisation of medical services, and the pattern of these injuries and referral patterns to hospitals. RESULTS: Medical encounters for non-athletes represented 40.9% of the total medical encounters. The rate of heat illnesses was low for athletes at 1.7% (N = 13). The total hospitalisation rate was low at 1.7% (n = 23). Utilisation of onsite pharmacy and physiotherapy services were high at 45.2% (n = 887) and 37.8% (n = 743), respectively, of the encounters for all support services. CONCLUSION: The dispersed nature of the Games venues provided challenges to the organisation of medical cover for the participants. Organisers in future Games can make use of the data to plan for future Games of a similar nature.

Dehydration rates and rehydration efficacy of water and sports drink during one hour of moderate intensity exercise in well-trained flatwater kayakers.

INTRODUCTION: The aim of this study is to investigate the amount of water loss and percentage dehydration experienced during 1 hour of paddling on the kayak ergometer so as to help coaches and athletes tailor a suitable and adequate rehydration regime. Also, rehydration efficacy between water and a well established, commercially available sports drink (Gatorade, Quaker Oats company, USA) was investigated in this cross-over study. MATERIALS AND METHODS: Ten national flatwater kayakers were monitored in a controlled setting while paddling the kayak ergometer for 1 hour at an intensity sustainable for long distance marathon. They rehydrated themselves ad libitum with provided beverage. Post-void towel-dried body mass was measured before and after the exercise with percentage dehydration calculated. Body core temperature (tympanic temperatures), ratings of perceived exertion and thirst index were monitored every 15 minutes. The amount of fluid consumed, urine output and urine specific gravity were obtained after exercise. RESULTS: The results [mean +/- standard deviation (SD)] showed that kayakers underwent 1.10 +/- 0.52% dehydration while rehydrating with water as compared to 0.72 +/- 0.38% while rehydrating with Gatorade. Also, athletes on water rehydration had higher rating of perceived exertion (RPE) at the 30th and 60th minute mark of the exercise. Overall, athletes undergoing water rehydration lost significantly more body mass (0.70 +/- 0.39 kg) as compared to rehydrating with Gatorade (0.46 +/- 0.27). CONCLUSION: Although the hydration efficacy of Gatorade proved superior to that of water, the athletes' hydration habits with either fluids did not provide adequate hydration. It is recommended that specific strategies be developed to address dehydration and rehydration issues of kayakers in Singapore.