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Setting the Stage for Chronic Health Problems: Cumulative Childhood Adversity among Homeless Adults with Mental Illness in Vancouver, British Columbia

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014
Abstract: 

Background

It is well documented that childhood abuse, neglect and household dysfunction are disproportionately present in the backgrounds of homeless adults, and that these experiences adversely impact child development and a wide range of adult outcomes. However, few studies have examined the cumulative impact of adverse childhood experiences on homeless adults with mental illness. This study examines adverse events in childhood as predictors of duration of homelessness, psychiatric and substance use disorders, and physical health in a sample of homeless adults with mental illness.

Methods

This study was conducted using baseline data from a randomized controlled trial in Vancouver, British Columbia for participants who completed the Adverse Childhood Experiences (ACE) scale at 18 months follow-up (n = 364). Primary outcomes included current mental disorders; substance use including type, frequency and severity; physical health; duration of homelessness; and vocational functioning.

Results

In multivariable regression models, ACE total score independently predicted a range of mental health, physical health, and substance use problems, and marginally predicted duration of homelessness.

Conclusions

Adverse childhood experiences are overrepresented among homeless adults with complex comorbidities and chronic homelessness. Our findings are consistent with a growing body of literature indicating that childhood traumas are potent risk factors for a number of adult health and psychiatric problems, particularly substance use problems. Results are discussed in the context of cumulative adversity and self-trauma theory.

Trials registration

This trial has been registered with the International Standard Randomized Control Trial Number Register and assigned ISRCTN42520374.

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Article
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Diabetes in Pregnancy among First Nations Women in Alberta, Canada: A Retrospective Analysis

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014
Abstract: 

Background

In addition to increasing the risk of adverse birth outcomes, diabetes in pregnancy is thought to be an important driver of the epidemic of type 2 diabetes affecting Canada’s First Nations population. The relative contributions of gestational diabetes mellitus (GDM) and pre-existing diabetes are not well understood. We generated a comprehensive epidemiological profile of diabetes in pregnancy over a 10-year period among the First Nations population of Alberta, Canada.

Methods

De-identified administrative data for 427,058 delivery records were obtained for the years 2000–2009. Pregnancy risk factors and delivery outcomes were described and compared by ethnicity (First Nations vs. non-First Nations) and diabetes status. Age-adjusted prevalence values for GDM and pre-existing diabetes were calculated and were compared by ethnicity. Longitudinal changes over time were also examined. Predictors were explored using logistic regression analysis.

Results

First Nations women had more antenatal risk factors and adverse infant outcomes that were compounded by diabetes. First Nations descent was an independent predictor of diabetes in pregnancy (p < 0.001). GDM prevalence was significantly higher among First Nations (6.1%) compared to non-First Nations women (3.8%; p < 0.001), but prevalence values increased significantly over time only in non-First Nations women (4.5 average annual percent change; p < 0.05). The prevalence of pre-existing diabetes was stable over time in both groups, but First Nations women experienced a 2.5-fold higher overall prevalence compared with non-First Nations women (1.5% vs. 0.6%, respectively; p < 0.001).

Conclusions

Although First Nations women experience a higher overall prevalence of diabetes in pregnancy, the lack of increase in the prevalence over time is encouraging. However, because high-risk pregnancies and poor outcomes are more common among First Nations women, particularly those with diabetes, strategies to improve perinatal care must be implemented.

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Article
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Stakeholder Views of Ethical Guidance Regarding Prevention and Care in HIV Vaccine Trials

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014
Abstract: 

Background

South Africa is a major hub of HIV prevention trials, with plans for a licensure trial to start in 2015. The appropriate standards of care and of prevention in HIV vaccine trials are complex and debated issues and ethical guidelines offer some direction. However, there has been limited empirical exploration of South African stakeholders’ perspectives on ethical guidance related to prevention and care in HIV vaccine trials.

Methods

Site staff, Community Advisory Board members and Research Ethics Committee members involved with current HIV vaccine trials in South Africa were invited to participate in an exploration of their views. A questionnaire listed 10 care and 10 prevention recommendations drawn from two widely available sets of ethical guidelines for biomedical HIV prevention trials. Respondents (n = 98) rated each recommendation on five dimensions: “Familiarity with”, “Ease of Understanding”, “Ease of Implementing”, “Perceived Protection”, and “Agreement with” each ethical recommendation. The ratings were used to describe stakeholder perspectives on dimensions for each recommendation. Dimension ratings were averaged across the five dimensions and used as an indication of overall merit for each recommendation. Differences were explored across dimensions, between care-oriented and prevention-oriented recommendations, and between stakeholder groups.

Results

Both care and prevention recommendations were rated highly overall, with median ratings well above the scale midpoint. In general, informed consent recommendations were most positively rated. Care-related recommendations were rated significantly more positively than prevention-related recommendations, with the five lowest-rated recommendations being prevention-related. The most problematic dimension across all recommendations was “Ease of Implementing,” and the least problematic was “Agreement with,” suggesting the most pressing stakeholder concerns are practical rather than theoretical; that is, respondents agree with but see barriers to the attainment of these recommendations.

Conclusions

We propose that prevention recommendations be prioritized for refinement, especially those assigned bottom-ranking scores for “Ease of Implementing”, and/ or “Ease of Understanding” in order to assist vaccine stakeholders to better comprehend and implement these recommendations. Further qualitative research could also assist to better understand nuances in stakeholder reservations about implementing such recommendations.

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Article
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Early Immune Adaptation in HIV-1 Revealed By Population-Level Approaches

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014
Abstract: 

Background

The reproducible nature of HIV-1 escape from HLA-restricted CD8+ T-cell responses allows the identification of HLA-associated viral polymorphisms “at the population level” – that is, via analysis of cross-sectional, linked HLA/HIV-1 genotypes by statistical association. However, elucidating their timing of selection traditionally requires detailed longitudinal studies, which are challenging to undertake on a large scale. We investigate whether the extent and relative timecourse of immune-driven HIV adaptation can be inferred via comparative cross-sectional analysis of independent early and chronic infection cohorts.

Results

Similarly-powered datasets of linked HLA/HIV-1 genotypes from individuals with early (median < 3 months) and chronic untreated HIV-1 subtype B infection, matched for size (N > 200/dataset), HLA class I and HIV-1 Gag/Pol/Nef diversity, were established. These datasets were first used to define a list of 162 known HLA-associated polymorphisms detectable at the population level in cohorts of the present size and host/viral genetic composition. Of these 162 known HLA-associated polymorphisms, 15% (occurring at 14 Gag, Pol and Nef codons) were already detectable via statistical association in the early infection dataset at p ≤ 0.01 (q < 0.2) – identifying them as the most consistently rapidly escaping sites in HIV-1. Among these were known rapidly-escaping sites (e.g. B*57-Gag-T242N) and others not previously appreciated to be reproducibly rapidly selected (e.g. A*31:01-associated adaptations at Gag codons 397, 401 and 403). Escape prevalence in early infection correlated strongly with first-year escape rates (Pearson’s R = 0.68, p = 0.0001), supporting cross-sectional parameters as reliable indicators of longitudinally-derived measures. Comparative analysis of early and chronic datasets revealed that, on average, the prevalence of HLA-associated polymorphisms more than doubles between these two infection stages in persons harboring the relevant HLA (p < 0.0001, consistent with frequent and reproducible escape), but remains relatively stable in persons lacking the HLA (p = 0.15, consistent with slow reversion). Published HLA-specific Hazard Ratios for progression to AIDS correlated positively with average escape prevalence in early infection (Pearson’s R = 0.53, p = 0.028), consistent with high early within-host HIV-1 adaptation (via rapid escape and/or frequent polymorphism transmission) as a correlate of progression.

Conclusion

Cross-sectional host/viral genotype datasets represent an underutilized resource to identify reproducible early pathways of HIV-1 adaptation and identify correlates of protective immunity.

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Article
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A Scoping Study to Identify Opportunities to Advance the Ethical Implementation and Scale-Up of HIV Treatment as Prevention: Priorities for Empirical Research

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014
Abstract: 

Background

Despite the evidence showing the promise of HIV treatment as prevention (TasP) in reducing HIV incidence, a variety of ethical questions surrounding the implementation and “scaling up” of TasP have been articulated by a variety of stakeholders including scientists, community activists and government officials. Given the high profile and potential promise of TasP in combatting the global HIV epidemic, an explicit and transparent research priority-setting process is critical to inform ongoing ethical discussions pertaining to TasP.

Methods

We drew on the Arksey and O’Malley framework for conducting scoping review studies as well as systematic approaches to identifying empirical and theoretical gaps within ethical discussions pertaining to population-level intervention implementation and scale up. We searched the health science database PubMed to identify relevant peer-reviewed articles on ethical and implementation issues pertaining to TasP. We included English language articles that were published after 2009 (i.e., after the emergence of causal evidence within this field) by using search terms related to TasP. Given the tendency for much of the criticism and support of TasP to occur outside the peer-reviewed literature, we also included grey literature in order to provide a more exhaustive representation of how the ethical discussions pertaining to TasP have and are currently taking place. To identify the grey literature, we systematically searched a set of search engines, databases, and related webpages for keywords pertaining to TasP.

Results

Three dominant themes emerged in our analysis with respect to the ethical questions pertaining to TasP implementation and scale-up: (a) balancing individual- and population-level interests; (b) power relations within clinical practice and competing resource demands within health care systems; (c) effectiveness considerations and socio-structural contexts of HIV treatment experiences within broader implementation contexts.

Conclusion

Ongoing research and normative deliberation is required in order to successfully and ethically scale-up TasP within the continuum of HIV care models. Based on the results of this scoping review, we identify several ethical and implementation dimensions that hold promise for informing the process of scaling up TasP and that could benefit from new research.

Document type: 
Article
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The Multiple Meanings of Global Health Governance: A Call for Conceptual Clarity

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014
Abstract: 

Background

The term global health governance (GHG) is now widely used, with over one thousand works published in the scholarly literature, almost all since 2002. Amid this rapid growth there is considerable variation in how the term is defined and applied, generating confusion as to the boundaries of the subject, the perceived problems in practice, and the goals to be achieved through institutional reform.

Methodology

This paper is based on the results of a separate scoping study of peer reviewed GHG research from 1990 onwards which undertook keyword searches of public health and social science databases. Additional works, notably books, book chapters and scholarly articles, not currently indexed, were identified through Web of Science citation searches. After removing duplicates, book reviews, commentaries and editorials, we reviewed the remaining 250 scholarly works in terms of how the concept of GHG is applied. More specifically, we identify what is claimed as constituting GHG, how it is problematised, the institutional features of GHG, and what forms and functions are deemed ideal.

Results

After examining the broader notion of global governance and increasingly ubiquitous term “global health”, the paper identifies three ontological variations in GHG scholarship - the scope of institutional arrangements, strengths and weaknesses of existing institutions, and the ideal form and function of GHG. This has produced three common, yet distinct, meanings of GHG that have emerged – globalisation and health governance, global governance and health, and governance for global health.

Conclusions

There is a need to clarify ontological and definitional distinctions in GHG scholarship and practice, and be critically reflexive of their normative underpinnings. This will enable greater precision in describing existing institutional arrangements, as well as serve as a prerequisite for a fuller debate about the desired nature of GHG.

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Article
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The Economic Burden of Prematurity in Canada

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014
Abstract: 

Background

Preterm birth is a major risk factor for morbidity and mortality among infants worldwide, and imposes considerable burden on health, education and social services, as well as on families and caregivers. Morbidity and mortality resulting from preterm birth is highest among early (< 28 weeks gestational age) and moderate (28–32 weeks) preterm infants, relative to late preterm infants (33–36 weeks). However, substantial societal burden is associated with late prematurity due to the larger number of late preterm infants relative to early and moderate preterm infants.

Methods

The aim in this study was to characterize the burden of premature birth in Canada for early, moderate, and late premature infants, including resource utilization, direct medical costs, parental out-of-pocket costs, education costs, and mortality, using a validated and published decision model from the UK, and adapting it to a Canadian setting based on analysis of administrative, population-based data from Québec.

Results

Two-year survival was estimated at 56.0% for early preterm infants, 92.8% for moderate preterm infants, and 98.4% for late preterm infants. Per infant resource utilization consistently decreased with age. For moderately preterm infants, hospital days ranged from 1.6 at age two to 0.09 at age ten. Cost per infant over the first ten years of life was estimated to be $67,467 for early preterm infants, $52,796 for moderate preterm infants, and id="mce_marker"0,010 for late preterm infants. Based on population sizes this corresponds to total national costs of id="mce_marker"23.3 million for early preterm infants, $255.6 million for moderate preterm infants, $208.2 million for late preterm infants, and $587.1 million for all infants.

Conclusion

Premature birth results in significant infant morbidity, mortality, healthcare utilization and costs in Canada. A comprehensive decision-model based on analysis of a Canadian population-based administrative data source suggested that the greatest national-level burden is associated with moderate preterm infants due to both a large cost per infant and population size while the highest individual-level burden is in early preterm infants and the largest total population size is in late preterm infants. Although the highest medical costs are incurred during the neonatal period, greater resource utilization and costs extend into childhood.

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Article
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Generating GPS Activity Spaces That Shed Light upon the Mobility Habits of Older Adults: A Descriptive Analysis

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014
Abstract: 

Background

Measuring mobility is critical for understanding neighborhood influences on older adults’ health and functioning. Global Positioning Systems (GPS) may represent an important opportunity to measure, describe, and compare mobility patterns in older adults.

Methods

We generated three types of activity spaces (Standard Deviation Ellipse, Minimum Convex Polygon, Daily Path Area) using GPS data from 95 older adults in Vancouver, Canada. Calculated activity space areas and compactness were compared across sociodemographic and resource characteristics.

Results

Area measures derived from the three different approaches to developing activity spaces were highly correlated. Participants who were younger, lived in less walkable neighborhoods, had a valid driver’s license, had access to a vehicle, or had physical support to go outside of their homes had larger activity spaces. Mobility space compactness measures also differed by sociodemographic and resource characteristics.

Conclusions

This research extends the literature by demonstrating that GPS tracking can be used as a valuable tool to better understand the geographic mobility patterns of older adults. This study informs potential ways to maintain older adult independence by identifying factors that influence geographic mobility.

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Article
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The Limits of Global Health Diplomacy: Taiwan's Observer Status at the World Health Assembly

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014
Abstract: 

In 2009, health authorities from Taiwan (under the name “Chinese Taipei”)a formally attended the 62nd World Health Assembly (WHA) of the World Health Organization as observers, marking the country’s participation for the first time since 1972. The long process of negotiating this breakthrough has been cited as an example of successful global health diplomacy. This paper analyses this negotiation process, drawing on government documents, formal representations from both sides of the Taiwan Strait, and key informant interviews. The actors and their motivations, along with the forums, practices and outcomes of the negotiation process, are detailed. While it is argued that non-traditional diplomatic action was important in establishing the case for Taiwan’s inclusion at the WHA, traditional concerns regarding Taiwanese sovereignty and diplomatic representation ultimately played a decisive role. The persistent influence of these traditional diplomatic questions illustrates the limits of global health diplomacy.

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