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Validating A Self-Report Measure Of HIV Viral Suppression: An Analysis of Linked Questionnaire and Clinical Data from the Canadian HIV Women’s Sexual And Reproductive Health Cohort Study

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2017-03-24
Abstract: 

Background  We assessed the validity of a self-report measure of undetectable viral load (VL) among women with HIV in British Columbia (BC), Canada. Questionnaire data from the Canadian HIV Women’s Sexual and Reproductive Health Cohort Study was linked with population-based clinical data from the BC Centre for Excellence in HIV/AIDS. Self-reported undetectable VL was assessed by the question: “What was your most recent VL, undetectable (i.e. <50 copies/mL) or detectable (i.e. ≥50 copies/mL)?” Laboratory measurements of VL <50 copies/mL (closest to/before study visit) were the criterion for validity analyses. We measured positive and negative predictive values (PPV, NPV) and likelihood ratios (LR+, LR−).

Results  Of 356 participants, 99% were linked to clinical data. Those unlinked (n = 1), missing self-report VL (n = 18), or missing self-report and laboratory VL (n = 1) were excluded. Among the remaining 336: median age was 44 (IQR 37–51); 96% identified as cis-gender; 84% identified as heterosexual; and 45% identified as Indigenous, 40% White, 8% African, Caribbean, or Black, and 8% other/multiple ethnicities. Overall, 85% self-reported having an undetectable VL while 82% had clinical data indicating viral suppression. The PPV was 93.7 (95% CI 90.2–96.2) indicating that 94% of women who self-reported being undetectable truly were. The NPV was 80.4 (95% CI 66.9–90.2). LR+ was 3.2 (2.1–4.6) and LR− was 0.05 (0.03–0.10).

Conclusions  Our self-report measure assessing undetectable VL strongly predicted true viral suppression among Canadian women with HIV. This measure can be used in research settings without laboratory data in regions with high rates of VL testing and suppression.

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Changes in Mortality Rates and Causes of Death in a Population-based Cohort of Persons Living with and Without HIV from 1996 to 2012

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2017-02-27
Abstract: 

Background  Non-HIV/AIDS-related diseases are gaining prominence as important causes of morbidity and mortality among people living with HIV. The purpose of this study was to characterize and compare changes over time in mortality rates and causes of death among a population-based cohort of persons living with and without HIV in British Columbia (BC), Canada.

Methods  We analysed data from the Comparative Outcomes And Service Utilization Trends (COAST) study; a retrospective population-based study created via linkage between the BC Centre for Excellence in HIV/AIDS and Population Data BC, and containing data for HIV-infected individuals and the general population of BC, respectively. Our analysis included all known HIV-infected adults (≥ 20 years) in BC and a random 10% sample of uninfected BC adults followed from 1996 to 2012. Deaths were identified through Population Data BC – which contains information on all registered deaths in BC (BC Vital Statistics Agency dataset) and classified into cause of death categories using International Classification of Diseases (ICD) 9/10 codes. Age-standardized mortality rates (ASMR) and mortality rate ratios were calculated. Trend test were performed.

Results  3401 (25%), and 47,647 (9%) individuals died during the 5,620,150 person-years of follow-up among 13,729 HIV-infected and 510,313 uninfected individuals, respectively. All-cause and cause-specific mortality rates were consistently higher among HIV-infected compared to HIV-negative individuals, except for neurological disorders. All-cause ASMR decreased from 126.75 (95% CI: 84.92-168.57) per 1000 population in 1996 to 21.29 (95% CI: 17.79-24.79) in 2011-2012 (83% decline; p < 0.001 for trend), compared to a change from 7.97 (95% CI: 7.61-8.33) to 6.87 (95% CI: 6.70-7.04) among uninfected individuals (14% decline; p < 0.001). Mortality rates from HIV/AIDS-related causes decreased by 94% from 103.85 per 1000 population in 1996 to 6.72 by the 2011–2012 era (p < 0.001). Significant ASMR reductions were also observed for hepatic/liver disease and drug abuse/overdose deaths. ASMRs for neurological disorders increased significantly over time. Non-AIDS-defining cancers are currently the leading non-HIV/AIDS-related cause of death in both HIV-infected and uninfected individuals.

Conclusions  Despite the significant mortality rate reductions observed among HIV-infected individuals from 1996 to 2012, they still have excess mortality risk compared to uninfected individuals. Additional efforts are needed to promote effective risk factor management and appropriate screening measures among people living with HIV.

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High Prevalence of Quasi-legal Psychoactive Substance Use among Male Patients in HIV Care in Japan: A Cross-sectional Study

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2017-02-23
Abstract: 

Background  Syndemics of illicit drug use and HIV remain as significant public health issues around the world. There has been increasing concern regarding the rapidly growing market of new psychoactive substances, particularly in Asia. In response, the Japanese government has increasingly banned such substances in recent years. We sought to identify the prevalence and correlates of use of quasi-legal psychoactive substances among people living with HIV/AIDS (PLHIV) in Japan.

Methods  Data were derived from a nationwide survey of PLHIV conducted at nine leading HIV/AIDS care hospitals between July and December 2013. The prevalence and correlates of the use of quasi-legal psychoactive substances (e.g., synthetic cannabinoids, cathinone derivatives, etc. that had not been prohibited from using at the time of survey) among male participants were examined using multivariate survey logistic regression.

Results  Among 963 study participants, the majority (95.3%) were male. The most commonly used drug among men was quasi-legal psychoactive substances (55.3% ever and 12.8% in the previous year). In multivariate analysis, the lifetime use of tryptamine-type derivatives (i.e., 5-MeO-DIPT or N,N-diisopropyl-5-methoxytryptamine) (adjusted odds ratio [AOR]: 2.42; 95% confidence interval [CI]: 1.36–4.28) and methamphetamine/amphetamine (AOR: 3.59; 95% CI: 2.13–6.04) were independently associated with recent quasi-legal psychoactive substance use.

Conclusions  In our sample of male PLHIV in Japan, quasi-legal psychoactive substances were the most commonly used drugs. Individuals who had ever used tryptamine-type derivatives or methamphetamine/amphetamine were more likely to report recent quasi-legal psychoactive substance use, suggesting a potential shift in drug use patterns from regulated to unregulated substances among this population. These findings indicate a need for further research to examine implications for HIV care.

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Dual Sexual and Drug-related Predictors of Hepatitis C Incidence among Sex Workers in a Canadian Setting: Gaps and Opportunities for Scale-up of Hepatitis C Virus Prevention, Treatment, and Care

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2016-12-24
Abstract: 

Background  Hepatitis C virus (HCV) represents a significant cause of morbidity and mortality globally. While sex workers may face elevated HCV risks through both drug and sexual pathways, incidence data among sex workers are severely lacking. HCV incidence and predictors of HCV seroconversion among women sex workers in Vancouver, BC were characterized in this study.

Methods  Questionnaire and serological data were drawn from a community-based cohort of women sex workers (2010–2014). Kaplan–Meier methods and Cox regression were used to model HCV incidence and predictors of time to HCV seroconversion.

Results  Among 759 sex workers, HCV prevalence was 42.7%. Among 292 baseline-seronegative sex workers, HCV incidence density was 3.84/100 person-years (PY), with higher rates among women using injection drugs (23.30/100 PY) and non-injection crack (6.27/100 PY), and those living with HIV (13.27/100 PY) or acute sexually transmitted infections (STIs) (5.10/100 PY). In Cox analyses adjusted for injection drug use, age (hazard ratio (HR) 0.94, 95% confidence interval (CI) 0.86–1.01), acute STI (HR 2.49, 95% CI 1.02–6.06), and non-injection crack use (HR 2.71, 95% CI 1.18–6.25) predicted time to HCV seroconversion.

Discussion  While HCV incidence was highest among women who inject drugs, STIs and the use of non-injection stimulants appear to be pathways to HCV infection, suggesting potential dual sexual/drug transmission. Integrated HCV services within sexual health and HIV/STI programs are recommended.

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Association Between Internet Use and Body Dissatisfaction Among Young Females: Cross-Sectional Analysis of the Canadian Community Health Survey

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2017-02-17
Abstract: 

Background: Recent research suggests Internet exposure, including Facebook use, is positively correlated with body dissatisfaction, especially among girls and young women. Canada has one of the highest Internet access rates in the world, yet no previous study has examined this relationship using nationally representative data.

Objective: Our objective was to evaluate the relationship between Internet use and body dissatisfaction among a national, population-based sample of Canadian females 12-29 years of age.

Methods: We used cross-sectional data from the Canadian Community Health Survey 2011-2012. Body dissatisfaction was measured using a 5-point Likert scale and defined as “very dissatisfied/dissatisfied” with one’s body. The explanatory variable was time spent using the Internet per week in the past 3 months, ranging from none/<1 hour to >20 hours. We used multinomial logistic regression to investigate whether greater Internet use was associated with increasing odds of being very dissatisfied/dissatisfied, neutral, or satisfied with one’s body, using very satisfied as the referent. Probability survey sampling weights were applied to all analyses.

Results: Of 2983 included participants, sampled to represent 940,786 young Canadian females, most were 20-29 years old (61.98%) and living in households with an annual income Can $80,000 or more (44.61%). The prevalence of body dissatisfaction was 14.70%, and 25- to 29-year-olds were more likely than 12- to 14-year-olds to be very dissatisfied or dissatisfied with their body (20.76% vs 6.34%). Few (5.01%) reported none/<1 hour of Internet use, over half (56.93%) reported 1-10 hours, and one-fifth (19.52%) reported spending >20 hours online per week. Adjusting for age and income, the odds of being very dissatisfied/dissatisfied, relative to very satisfied, were greater in the highest versus lowest Internet use group (adjusted odds ratio [AOR] 3.03, 95% CI 1.19-7.70). The AORs for this level of body dissatisfaction increased across increasing levels of Internet use, ranging from 0.88 (95% CI 0.35-2.21) to 3.03 (95% CI 1.19-7.70). Additionally, those who spent 11-14 hours online were more likely to be neutral (AOR 3.66, 95% CI 1.17-11.45) and those who spent 15-20 hours online were more likely to be neutral (AOR 4.36, 95% CI 1.18-16.13) or satisfied (AOR 2.82, 95% CI 1.14-7.01) with their bodies, relative to very satisfied, compared with those spending no time or <1 hour online.

Conclusions: A substantial proportion of Canadian females 12-29 years of age spent large amounts of time (>20 hours) on the Internet each week, and body dissatisfaction was significantly more likely among this group. Those who spent 11-20 hours online were also more likely to be less satisfied with their bodies. Efforts are needed to support girls and young women to achieve and maintain a positive body image in today’s digital age.

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Declining Rates of Health Problems Associated with Crack Smoking During the Expansion of Crack Pipe Distribution in Vancouver, Canada

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2017-02-03
Abstract: 

Background  Crack cocaine smoking is associated with an array of negative health consequences, including cuts and burns from unsafe pipes, and infectious diseases such as HIV. Despite the well-established and researched harm reduction programs for injection drug users, little is known regarding the potential for harm reduction programs targeting crack smoking to reduce health problems from crack smoking. In the wake of recent crack pipe distribution services expansion, we utilized data from long running cohort studies to estimate the impact of crack pipe distribution services on the rates of health problems associated with crack smoking in Vancouver, Canada.

Methods  Data were derived from two prospective cohort studies of community-recruited people who inject drugs in Vancouver between December 2005 and November 2014. We employed multivariable generalized estimating equations to examine the relationship between crack pipe acquisition sources and self-reported health problems associated with crack smoking (e.g., cut fingers/sores, coughing blood) among people reported smoking crack.

Results  Among 1718 eligible participants, proportions of those obtaining crack pipes only through health service points have significantly increased from 7.2% in 2005 to 62.3% in 2014 (p < 0.001), while the rates of reporting health problems associated with crack smoking have significantly declined (p < 0.001). In multivariable analysis, compared to those obtaining pipes only through other sources (e.g., on the street, self-made), those acquiring pipes through health service points only were significantly less likely to report health problems from smoking crack (adjusted odds ratio: 0.82; 95% confidence interval: 0.73–0.93).

Conclusions  These findings suggest that the expansion of crack pipe distribution services has likely served to reduce health problems from smoking crack in this setting. They provide evidence supporting crack pipe distribution programs as a harm reduction service for crack smokers.

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Two Birds with One Stone: Experiences of Combining Clinical and Research Training in Addiction Medicine

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2017-01-23
Abstract: 

Background  Despite a large evidence-base upon which to base clinical practice, most health systems have not combined the training of healthcare providers in addiction medicine and research. As such, addiction care is often lacking, or not based on evidence or best practices. We undertook a qualitative study to assess the experiences of physicians who completed a clinician-scientist training programme in addiction medicine within a hospital setting.

Methods  We interviewed physicians from the St. Paul’s Hospital Goldcorp Addiction Medicine Fellowship and learners from the hospital’s academic Addiction Medicine Consult Team in Vancouver, Canada (N = 26). They included psychiatrists, internal medicine and family medicine physicians, faculty, mentors, medical students and residents. All received both addiction medicine and research training. Drawing on Kirkpatrick’s model of evaluating training programmes, we analysed the interviews thematically using qualitative data analysis software (Nvivo 10).

Results  We identified five themes relating to learning experience that were influential: (i) attitude, (ii) knowledge, (iii) skill, (iv) behaviour and (v) patient outcome. The presence of a supportive learning environment, flexibility in time lines, highly structured rotations, and clear guidance regarding development of research products facilitated clinician-scientist training. Competing priorities, including clinical and family responsibilities, hindered training.

Conclusions  Combined training in addiction medicine and research is feasible and acceptable for current doctors and physicians in training. However, there are important barriers to overcome and improved understanding of the experience of addiction physicians in the clinician-scientist track is required to improve curricula and research productivity.

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“We Think Globally”: The Rise of Paraguay’s Tabacalera Del Este as a Threat to Global Tobacco Control

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2018-11-19
Abstract: 

Background  Leading transnational tobacco companies (TTCs) began to expand their operations in Latin America in the 1960s. This included legally exporting their cigarettes to Paraguay during the 1960s which, in turn, were illegally re-exported to Argentina and Brazil. By the 1990s, competition between BAT and PMI for this lucrative illicit market, focusing on low-priced brands, prompted manufacturing in Paraguay. Paraguayan manufacturing rapidly grew after the introduction of a new cigarette export tax in Brazil in 1999.

Methods  We systematically searched Truth Tobacco Industry Documents (TTID) to understand the activities and strategies of leading TTCs in Paraguay and subregion over time. We applied the analytical framework of Lee and Eckhardt (2017) to understand Tabesa’s global business strategy. We searched the websites of TTCs and Tabesa for activities since the mid 2000s to understand how the companies publicly describe these strategies. We used the United Nations Commodity Trade Statistics Database (UN Comtrade) as an independent source to crosscheck statements by Tabesa executives about export markets. We contextualized and triangulated our findings with 42 key informant interviews.

Results  Tabesa became the largest cigarette manufacturer in Paraguay, and one of the largest companies in the country, through complicity in the illicit trade. Enabled by market conditions created by leading TTCs, and a permissive regulatory environment in Paraguay, evidence suggests Tabesa had become a major source of illicit cigarettes across Latin America and beyond by the late 2000s. Although Brazil continues to account for the bulk of Tabesa’s revenues, findings suggest that the company is aspiring to compete with TTCs in markets worldwide through legal and illegal sales.

Conclusion  There is a need for fuller understanding of the risks to global tobacco control from local companies aspiring to compete with TTCs. The rise of Tabesa is part of the changing nature of the illicit trade in tobacco products which must be taken into account in implementing the Framework Convention on Tobacco Control (FCTC) and its Protocol to Eliminate Illicit Trade in Tobacco Products. Potential conflicts of interest concerning Tabesa illustrate the importance of FCTC Article 5.3 on industry interference. There is also an urgent need to address the lack of independent and rigorous data on the illicit tobacco trade in the region.

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From Transit Hub to Major Supplier of Illicit Cigarettes to Argentina and Brazil: The Changing Role of Domestic Production and Transnational Tobacco Companies in Paraguay Between 1960 and 2003

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2018-11-19
Abstract: 

Background  Paraguay has reportedly been a major transit hub for illicit tobacco products since the 1960s, initially to supply markets in Argentina and Brazil and, more recently, other regional markets and beyond. However, to date there has been no systematic analysis, notably independent of the tobacco industry, of this trade including the roles of domestic production and transnational tobacco companies (TTCs). This article fills that gap by detailing the history of Paraguay’s illicit cigarette trade to Brazil and Argentina of TTC products and Paraguayan production between 1960 and 2003. The effective control of illicit cigarette flows, under Article 15 of the World Health Organization (WHO) Framework Convention on Tobacco Control (FCTC) and the Protocol to Eliminate the Illicit Trade in Tobacco Products, requires fuller understanding of the changing nature of the illicit trade.

Methods  We systematically searched internal industry documents to understand the activities and strategies of leading TTCs in Paraguay and subregion over time. We also mapped illicit trade volume and patterns using US government and UN data on the cigarette trade involving Paraguay. We then estimated Paraguay’s cigarette production from 1989 to 2003 using tobacco leaf flows from the United Nations Commodity Trade Statistics Database (UN Comtrade).

Results  We identify four phases in the illicit tobacco trade involving Paraguay: 1) Paraguay as a transit hub to smuggle BAT and PMI cigarettes from the U.S. into Argentina and Brazil (from the 1960s to the mid-1970s); 2) BAT and PMI competing in north-east Argentina (1989–1994); 3) BAT and PMI competing in southern and southern-east Brazil (mid to late 1990s); and 4) the growth in the illicit trade of Paraguayan manufactured cigarettes (from the mid- 1990s onwards). These phases suggest the illicit trade was seeded by TTCs, and that the system of supply and demand on lower priced brands they developed in the 1990s created a business opportunity for manufacturing in Paraguay. Brazil’s efforts to fight this trade, with a 150% tax on exports to Latin American countries in 1999, further prompted supply of the illicit trade to shift from TTCs to Paraguayan manufacturers.

Conclusion  This paper extends evidence of the longstanding complicity of TTCs in the illicit trade to this region and the consequent growth of Paraguayan production in the 1990s. Our findings confirm the need to better understand the factors influencing how the illicit tobacco trade has changed over time, in specific regional contexts, and amid tobacco industry globalization. In Paraguay, the changing roles of TTC and domestic production have been central to shifting patterns of illicit supply and distribution since the 1960s. Important questions are raised, in turn, about TTCs efforts to participate as legitimate partners in global efforts to combat the problem, including a leading role in data gathering and analysis.

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A High Burden of Asymptomatic Genital Tract Infections Undermines the Syndromic Management Approach Among Adolescents and Young Adults in South Africa: Implications for HIV Prevention Efforts

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2018-10-03
Abstract: 

Background  Youth in southern Africa, particularly adolescent girls and young women, are a key population for HIV prevention interventions. Untreated genital tract infections (GTIs) increase both HIV transmission and acquisition risks. South African GTI treatment guidelines employ syndromic management, which relies on individuals to report GTI signs and symptoms. Syndromic management may, however, underestimate cases, particularly among youth. We compared genital tract infection (GTI) prevalence by symptom-based and laboratory assessment among sexually-experienced youth in South Africa, overall and stratified by sex.

Methods  Interviewer-administered surveys assessed socio-demographics, behaviors, and GTI symptoms among 352 youth (16-24 yrs., HIV-negative or unknown HIV status at enrollment) enrolled in community-based cohorts in Durban and Soweto (2014–2016). Laboratory tests assessed HIV, Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Mycoplasma genitalium (MG), Trichomonas vaginalis (TV) infections and, among females, bacterial vaginosis (BV) and Candida species. Youth with genital ulcers were tested for HSV-2 and syphilis. We assessed sensitivity (and specificity) of symptom-based reporting in identifying laboratory-confirmed GTIs.

Results  At baseline, 16.2% of females (32/198) and < 1% (1/154) of males reported ≥1 GTI symptom. However, laboratory tests identified ≥1 GTI in 70.2% and 10.4%, respectively. Female CT prevalence was 18.2%, NG 7.1%, MG 9.6%, TV 8.1%, and 5.1% were newly diagnosed with HIV. BV prevalence was 53.0% and candidiasis 9.6%. One female case of herpes was identified (0 syphilis). Male CT prevalence was 7.8%, NG 1.3%, MG 3.3%, TV < 1%, and 2.0% were newly diagnosed with HIV. Overall, 77.8% of females and 100% of males with laboratory-diagnosed GTIs reported no symptoms or were asymptomatic. Sensitivity (and specificity) of symptom-based reporting was 14% (97%) among females and 0% (99%) among males.

Conclusion  A high prevalence of asymptomatic GTIs and very poor sensitivity of symptom-based reporting undermines the applicability of syndromic GTI management, thus compromising GTI control and HIV prevention efforts among youth. Syndromic GTI management does not meet the sexual health needs of young people. Policy changes incorporating innovations in GTI diagnostic testing are needed to reduce GTIs and HIV-associated risks among youth.

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