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Women’s Health Care Utilization among Harder-to-Reach HIV-Infected Women ever on Antiretroviral Therapy in British Columbia

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2012
Abstract: 

Background. HIV-infected women are disproportionately burdened by gynaecological complications, psychological disorders, and certain sexually transmitted infections that may not be adequately addressed by HIV-specific care. We estimate the prevalence and covariates of women’s health care (WHC) utilization among harder-to-reach, treatment-experienced HIV-infected women in British Columbia (BC), Canada. Methods. We used survey data from 231 HIV-infected, treatment-experienced women enrolled in the Longitudinal Investigations into Supportive and Ancillary Health Services (LISA) study, which recruited harder-to-reach populations, including aboriginal people and individuals using injection drugs. Independent covariates of interest included sociodemographic, psychosocial, behavioural, individual health status, structural factors, and HIV clinical variables. Logistic regression was used to generate adjusted estimates of associations between use of WHC and covariates of interest. Results. Overall, 77% of women reported regularly utilizing WHC. WHC utilization varied significantly by region of residence (P value <0.01). In addition, women with lower annual income (AOR (95% CI) = 0.14 (0.04–0.54)), who used illicit drugs (AOR (95% CI) = 0.42 (0.19–0.92)) and who had lower provider trust (AOR (95% CI) = 0.97 (0.95–0.99)), were significantly less likely to report using WHC. Conclusion. A health service gap exists along geographical and social axes for harder-to-reach HIV-infected women in BC. Women-centered WHC and HIV-specific care should be streamlined and integrated to better address women’s holistic health.

Document type: 
Article

“We Are Not Being Heard”: Aboriginal Perspectives on Traditional Foods Access and Food Security

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2012
Abstract: 

Aboriginal peoples are among the most food insecure groups in Canada, yet their perspectives and knowledge are often sidelined in mainstream food security debates. In order to create food security for all, Aboriginal perspectives must be included in food security research and discourse. This project demonstrates a process in which Aboriginal and non-Aboriginal partners engaged in a culturally appropriate and respectful collaboration, assessing the challenges and barriers to traditional foods access in the urban environment of Vancouver, BC, Canada. The findings highlight local, national, and international actions required to increase access to traditional foods as a means of achieving food security for all people. The paper underscores the interconnectedness of local and global food security issues and highlights challenges as well as solutions with potential to improve food security of both Aboriginal and non-Aboriginal peoples alike.

Document type: 
Article

Addressing the Younger Age at Onset in Breast Cancer Patients in Asia: An Age-Period-Cohort Analysis of Fifty Years of Quality Data from the International Agency for Research on Cancer

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2013
Abstract: 

There is an established fact that Asian breast cancer patients are, on average, younger than their European counterparts. This study aimed to utilize the data from the Cancer Incidence in Five Continents I through XIII (published by the International Agency for Research on Cancer) to examine what contributes to the younger age at onset in the Asian population. Material and Methods. Data (number of breast cancer cases and corresponding population figures) for 29 registries in Europe and 9 registries in Asia for the period of 1953–2002 was accessioned and pooled to form two distinct populations, Asia and Europe. The age specific rates were defined and analyzed cross-sectionally (period wise) and longitudinally (cohort wise). The magnitude and the pattern of age specific rates were analyzed using the age-period-cohort analysis. The constrained generalized linear model with a priority assumption of cohort effect as contributing factor to changing rates was used to analyze the data. Result. During the last 50 years, the rate of breast cancer increased for both populations with an estimated annual percent change of 1.03% (with 95% CI of 1.029, 1.031) for Asia and 1.016% (95% CI of 1.015, 1.017) for Europe. There were stronger cohort effects in the magnitude of rates among the Asian population compared to the European population. The cohort effects, expressed as the rate ratio with cohort born in 1970 as reference, ranged from 0.06 (95% CI 0.05, 0.08) to 0.94 (95% CI 0.93, 0.96) for Asians and 0.35 (95% CI 0.33, 0.36) to 1.03 (95% CI 1.02, 1.04) for Europeans. The estimated longitudinal age specific rates (adjusted for cohort and period effects) showed similar patterns between the two populations. Conclusion. It was concluded that a strong cohort effect contributes to the younger age at onset among Asian breast cancer patients.

Document type: 
Article

Evidence of Differential HLA Class I-Mediated Viral Evolution in Functional and Accessory/Regulatory Genes of HIV-1

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2007
Abstract: 

Despite the formidable mutational capacity and sequence diversity of HIV-1, evidence suggests that viral evolution in response to specific selective pressures follows generally predictable mutational pathways. Population-based analyses of clinically derived HIV sequences may be used to identify immune escape mutations in viral genes; however, prior attempts to identify such mutations have been complicated by the inability to discriminate active immune selection from virus founder effects. Furthermore, the association between mutations arising under in vivo immune selection and disease progression for highly variable pathogens such as HIV-1 remains incompletely understood. We applied a viral lineage-corrected analytical method to investigate HLA class I-associated sequence imprinting in HIV protease, reverse transcriptase (RT), Vpr, and Nef in a large cohort of chronically infected, antiretrovirally naïve individuals. A total of 478 unique HLA-associated polymorphisms were observed and organized into a series of “escape maps,” which identify known and putative cytotoxic T lymphocyte (CTL) epitopes under selection pressure in vivo. Our data indicate that pathways to immune escape are predictable based on host HLA class I profile, and that epitope anchor residues are not the preferred sites of CTL escape. Results reveal differential contributions of immune imprinting to viral gene diversity, with Nef exhibiting far greater evidence for HLA class I-mediated selection compared to other genes. Moreover, these data reveal a significant, dose-dependent inverse correlation between HLA-associated polymorphisms and HIV disease stage as estimated by CD4+ T cell count. Identification of specific sites and patterns of HLA-associated polymorphisms across HIV protease, RT, Vpr, and Nef illuminates regions of the genes encoding these products under active immune selection pressure in vivo. The high density of HLA-associated polymorphisms in Nef compared to other genes investigated indicates differential HLA class I-driven evolution in different viral genes. The relationship between HLA class I-associated polymorphisms and lower CD4+ cell count suggests that immune escape correlates with disease status, supporting an essential role of maintenance of effective CTL responses in immune control of HIV-1. The design of preventative and therapeutic CTL-based vaccine approaches could incorporate information on predictable escape pathways.

Document type: 
Article
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Determinants of Treatment Access in a Population-Based Cohort of HIV-Positive Men and Women Living in Argentina

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2008
Abstract: 

Objective: To report emerging data on the use of highly active antiretroviral therapy (HAART)in Argentina by assessing patterns of HAART access and late vs early treatment initiation in apopulation-based cohort of adults infected with HIV type-1.Design: The Prospective Study on the Use and Monitoring of Antiretroviral Therapy (PUMA) is astudy of 883 HIV-positive individuals enrolled in the Argentinean drug treatment program.Individuals were 16 years of age and older and were recruited from 10 clinics across Argentina.Methods: Sociodemographic and clinical characteristics were examined using contingency tables(Pearson chi-square test and Fisher exact test) for categoric variables and Wilcoxon rank-sum testfor continuous variables. To analyze time to initiation of HAART we used Kaplan-Meier methodsand Cox regression.Results: Patients who initiated HAART were more likely to be older, have an AIDS-defining illness,be an injection drug user (IDU), have a lower median CD4 cell count, have a higher median viralload, and be less likely to be men who have sex with men (MSM). In multivariate analysis, AIDSdefiningillness and plasma viral load were significantly associated with time to starting therapy.Patients who received late access were more likely to be diagnosed with AIDS and have highermedian plasma viral loads than those receiving early access.Conclusion: Our results indicate that despite free availability of treatment, monitoring, and carein Argentina, a significant proportion of men and women are accessing HAART late in the courseof HIV disease. Further characterization of the HIV-positive population will allow for a morecomprehensive evaluation of the impact of HAART within the Argentinean drug treatmentprogram.

Document type: 
Article
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Traditional Chinese Medicines In The Treatment of Hepatocellular Cancers: A Systematic Review and Meta-Analysis

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2009
Abstract: 

Background:

Liver cancer is a common malignancy with a high mortality rate. Given the poorprognosis associated with this cancer, many patients seek additional therapies that may improvequality of life or survival. Several Traditional Chinese Medicines (TCM) have been evaluated inclinical trials, but little is known about them outside of China.

Methods:

We searched independently and in duplicate 8 electronic databases, including 2 Chineselanguage databases, until February 2009. We included any randomized clinical trials (RCT)evaluating a TCM oral preparation for the treatment of hepatocellular cancers. We abstracted dataon survival, tumor response, and performance scores. We conducted a random-effects metaanalysisand applied a meta-regression analysis.

Results:

We included 45 RCTs (n = 3,236). All studies employed an active control group. Ingeneral, the reporting of methodological issues was poor. We analyzed data from 37 trialsreporting on complete response effects score (Relative Risk [RR] of 1.26 (95 CI, 1.04–1.52, P =0.01, I2 = 0%, P = 0.99). Products containing ginseng, astragalus and mylabris had a larger treatmenteffect (OR 1.34, 95% CI, 1.04–1.71, P = 0.01) than the pooled broad estimate, also the case forastragalus-based treatments (OR 1.35, 95% CI, 1.001–1.80. P = 0.048). We examined survival ratesand pooled 15 studies reporting on 6 month outcomes (RR 1.10, 95% CI, 1.04–1.15, P = < 0.0001,I2 = 0%, P = 0.60). This effect was consistent at other prospective dates, including 12 months (22trials, RR 1.26, 95% CI, 1.17–1.36, P = < 0.0001, I2 = 7%, P = 0.36), 24 months (15 trials, 1.72, 95%CI, 1.40–2.03, P = < 0.0001, I2 = 0%, P = 0.75); and, at 36 months (8 trials, RR 2.40, 95% CI, 1.65–3.49, P = < 0.0001, I2 = 0%, P = 0.62).

Limitations:

All included trials were conducted in China where emerging evidence suggests manyRCTs are not, in fact, randomized. Publication bias may exist, favouring positive reports.

Conclusion:

Our meta-analysis displays compelling evidence of effectiveness for hepatocellularcancers that should be evaluated in high-quality and transparent clinical trials.

Document type: 
Article

Rates of Inappropriate Antiretroviral Prescription Among Injection Drug Users

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2007
Abstract: 

Background: Although the survival benefits of antiretroviral therapy (ART) for the treatment of HIVinfection are well established, the clinical management of HIV disease continues to present majorchallenges. There are particular concerns regarding access to appropriate HIV treatment among HIVinfectedinjection drug users (IDU).Methods: In a prospective cohort study of HIV-infected IDU in Vancouver, Canada, we examined initialART regimens vis-à-vis the provincial government's therapeutic guidelines at the time ART was initiated.Briefly, there have been four sets of guidelines: Era 1 (1992 to November 1995; double-drug (dual NRTIs)ART for patients with a CD4 cell count of 350 or less); Era 2 (December 1995 to May 1996; double-drugtherapy for patients with a CD4+ cell count of 500 or less); Era 3 (June 1996 to June 1997; triple-drugtherapy (dual NRTIs with a PI or NNRTI) for patients who had a plasma viral load of > 100,000 HIV-1RNA copies/mL; dual therapy with two NRTIs for those with a plasma viral load of 5,000 to 100,000 HIV-1 RNA copies/mL); Era 4 (since July 1997; universal use of triple drug therapy as first-line treatment).Results: Between May 1996 and May 2003, 431 HIV-infected individuals were enrolled into the cohort.By May 31, 2003, 291 (67.5%) individuals had initiated ART. We noted instances of inappropriateantiretroviral prescription in each guideline era, with 9 (53%) in Era 1, 3 (12%) in Era 2, 22 (28%) in Era 3,and 23 (15%) in Era 4. Of the 57 subjects who received an inappropriate ART regimen initially, 14 neverreceived the appropriate therapy; among the remaining 43, the median time to the initiation of a guidelineappropriateART regimen was 12 months (inter-quartile range 5 – 20).Conclusion: The present study identified measurable rates of guideline-inappropriate ART prescriptionfor patients who were injection drug users. Rates were highest in the era of dual therapy, although highrates persisted into the triple-therapy era. As therapeutic guidelines continue to evolve, it is critical thatmechanisms be put in place to ensure prescription of ART combinations for IDU that are consistent withcurrent expert recommendations.

Document type: 
Article

Uptake And Outcomes Of A Prevention-Of Mother-To-Child Transmission (PMTCT) Program in Zomba District, Malawi

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2011
Abstract: 

Background: HIV prevalence among pregnant women in Malawi is 12.6%, and mother-to-child transmission is amajor route of transmission. As PMTCT services have expanded in Malawi in recent years, we sought to determineuptake of services, HIV-relevant infant feeding practices and mother-child health outcomes.Methods: A matched-cohort study of HIV-infected and HIV-uninfected mothers and their infants at 18-20 monthspost-partum in Zomba District, Malawi. 360 HIV-infected and 360 HIV-uninfected mothers were identified throughregisters. 387 mother-child pairs were included in the study.Results: 10% of HIV-infected mothers were on HAART before delivery, 27% by 18-20 months post-partum. sd-NVPwas taken by 75% of HIV-infected mothers not on HAART, and given to 66% of infants. 18% of HIV-infectedmothers followed all current recommended PMTCT options. HIV-infected mothers breastfed fewer months thanHIV-uninfected mothers (12 vs.18, respectively; p < 0.01). 19% of exposed versus 5% of unexposed children haddied by 18-20 months; p < 0.01. 28% of exposed children had been tested for HIV prior to the study, 76% weretested as part of the study and 11% were found HIV-positive. HIV-free survival by 18-20 months was 66% (95%CI58-74). There were 11(6%) maternal deaths among HIV-infected mothers only.Conclusion: This study shows low PMTCT program efficiency and effectiveness under routine program conditionsin Malawi. HIV-free infant survival may have been influenced by key factors, including underuse of HAART,underuse of sd-NVP, and suboptimal infant feeding practices. Maternal mortality among HIV-infected womendemands attention; improved maternal survival is a means to improve infant survival.

Document type: 
Article

HIV Testing and Willingness to Get HIV Testing at a Peer-Run Drop-in Centre for People who Inject Drugs in Bangkok, Thailand

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2012
Abstract: 

Background: Regular HIV testing among people who inject drugs is an essential component of HIV preventionand treatment efforts. We explored HIV testing behaviour among a community-recruited sample of injection drugusers (IDU) in Bangkok, Thailand.Methods: Data collected through the Mitsampan Community Research Project were used to examine correlates ofHIV testing behaviour among IDU and to explore reasons for not being tested. Multivariate logistic regression wasused to examine factors associated with willingness to access HIV testing at the drug-user-run Mitsampan HarmReduction Centre (MSHRC).Results: Among the 244 IDU who participated in this study, 186 (76.2%) reported receiving HIV testing in theprevious six months. Enrolment in voluntary drug treatment (odds ratio [OR] = 2.34; 95% confidence interval [CI]:1.18 - 4.63) and the tenofovir trial (OR = 44.81; 95%CI: 13.44 - 149.45) were positively associated with having beentested, whereas MSHRC use (OR = 1.78; 95%CI: 0.96 - 3.29) was marginally associated with having been tested.56.9% of those who had not been tested reported in engaging in HIV risk behaviour in the past six months. 181(74.2%) participants were willing to be tested at the MSHRC if testing were offered there. In multivariate analyses,willingness to get HIV testing at the MSHRC was positively associated with ever having been to the MSHRC(adjusted odds ratio [AOR] = 2.42; 95%CI: 1.21 - 4.85) and, among females, being enrolled in voluntary drugtreatment services (AOR = 9.38; 95%CI: 1.14 - 76.98).Conclusions: More than three-quarters of IDU received HIV testing in the previous six months. However, HIV riskbehaviour was common among those who had not been tested. Additionally, 74.2% of participants were willing toreceive HIV testing at the MSHRC. These findings provide evidence for ongoing HIV prevention education, as wellpotential benefits of incorporating HIV testing for IDU within peer-led harm reduction programs.

Document type: 
Article

Difficulty Accessing Crack Pipes and Crack Pipe Sharing Among People who Use Drugs in Vancouver, Canada

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2011
Abstract: 

Background: Crack pipe sharing can increase health risks among people who use drugs, yet the reasons forsharing these pipes have not been well described. Therefore, we sought to identify the prevalence and correlatesof crack pipe sharing among a community-recruited sample of people who use illicit drugs in Vancouver, a settingwhere crack pipes are provided at low or no cost.Findings: Data for this study were derived from two prospective cohorts of people who use drugs: the VancouverInjection Drug Users Study (VIDUS) and the AIDS Care Cohort to evaluate Exposure to Survival Services (ACCESS).Multivariate logistic regression was used to identify factors independently associated with crack pipe sharing.Among 503 crack users, 238 (47.3%) participants reported having shared a crack pipe in the previous six months.Having acquired a mouthpiece in the last six months (adjusted odds ratio [AOR] = 1.91; 95% confidence interval[CI]: 1.31 - 2.79) and difficulty finding new pipes (AOR = 2.19; 95%CI: 1.42 - 3.37) were positively associated withpipe sharing. Binge drug use (AOR = 1.39; 95%CI: 0.96 - 2.02) was marginally associated with sharing pipes.Discussion: There was a high prevalence of crack pipe sharing in a setting where crack pipes are distributed atlow or no cost. Difficulty accessing crack pipes was independently and positively associated with this behavior.These findings suggest that additional efforts are needed to discourage crack pipe sharing as well as increaseaccess to crack pipes.

Document type: 
Article