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Assessing the Impact of Food Insecurity on HIV Medication Adherence in the Context of an Integrated Care Facility for People Living with HIV in Vancouver, Canada

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2019-06-04
Abstract: 

Objective

Food insecurity, or self-reports of inadequate food access due to limited financial resources, remains prevalent among people living with HIV (PLHIV). We examined the impact of food insecurity on combination antiretroviral therapy (cART) adherence within an integrated care facility that provides services to PLHIV, including two meals per day.

Design

Adjusted odds ratios (aOR) were estimated by generalized estimating equations, quantifying the relationship between food insecurity (exposure) and cART adherence (outcome) with multivariable logistic regression.

Setting

We drew on survey data collected between February 2014-March 2016 from the Dr. Peter Centre Study based in Vancouver, Canada.

Participants

This study included 116 PLHIV at baseline, with 99 participants completing a 12-month follow-up interview. The median age was 46 years (IQR: 39-52) at baseline, and 82% (n=95) were biologically male at birth.

Results

At baseline, 74% (n=86) of participants were food insecure (≥ 2 affirmative responses on Health Canada’s Household Food Security Survey Module) and 67% (n=78) were adherent to cART ≥ 95% of the time. In the adjusted regression analysis, food insecurity was associated with suboptimal cART adherence (aOR=0.47, 95% confidence interval = 0.24-0.93).

Conclusions

While food provision may reduce some health-related harms, there remains a relationship between this prevalent experience and suboptimal cART adherence in this integrated care facility. Future studies that elucidate strategies to mitigate food insecurity and its affects on cART adherence among PLHIV in this setting and in other similar environments are necessary.

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Article
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Disease Burden and Government Spending On Mental, Neurological, And Substance Use Disorders, and Self-Harm: Cross-Sectional, Ecological Study of Health System Response in the Americas

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2018-11-14
Abstract: 

Background Disorders affecting mental health are highly prevalent, can be disabling, and are associated with substantial premature mortality. Yet national health system responses are frequently under-resourced, inefficient, and ineffective, leading to an imbalance between disease burden and health expenditures. We estimated the disease burden in the Americas caused by disorders affecting mental health. This measure was adjusted to include mental, neurological, and behavioural disorders that are frequently not included in estimates of mental health burden. We propose a framework for assessing the imbalance between disease burden and health expenditures.

Methods In this cross-sectional, ecological study, we extracted disaggregated disease burden data from the Global Health Data Exchange to produce country-level estimates for the proportion of total disease burden attributable to mental disorders, neurological disorders, substance use disorders, and self-harm (MNSS) in the Americas. We collated data from the WHO Assessment Instrument for Mental Health Systems and the WHO Mental Health Atlas on country-level mental health spending as a proportion of total government health expenditures, and of psychiatric hospital spending as a proportion of mental health expenditures. We used a metric capturing the imbalance between disease burden and mental health expenditures, and modelled the association between this imbalance and real (ie, adjusted for purchasing power parity) gross domestic product (GDP).

Findings Data were collected from July 1, 2016, to March 1, 2017. MNSS comprised 19% of total disability-adjusted lifeyears in the Americas in 2015. Median spending on mental health was 2·4% (IQR 1·3–4·1) of government health spending, and median allocation to psychiatric hospitals was 80% (52–92). This spending represented an imbalance in the ratio between disease burden and efficiently allocated spending, ranging from 3:1 in Canada and the USA to 435:1 in Haiti, with a median of 32:1 (12–170). Mental health expenditure as a proportion of government health spending was positively associated with real GDP (β=0·68 [95% CI 0·24–1·13], p=0·0036), while the proportion allocated to psychiatric hospitals (β=–0·5 [–0·79 to –0·22], p=0·0012) and the imbalance in efficiently allocated spending (β=–1·38 [–1·97 to –0·78], p=0·0001) were both inversely associated with real GDP. All estimated coefficients were significantly different from zero at the 0·005 level.

Interpretation A striking imbalance exists between government spending on mental health and the related disease burden in the Americas, which disproportionately affects low-income countries and is likely to result in undertreatment, increased avoidable disability and mortality, decreased national economic output, and increased household-level health spending.

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Indigenous and Non-Indigenous People Experiencing Homelessness and Mental Illness in Two Canadian Cities: A Retrospective Analysis and Implications for Culturally Informed Action

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2019-04-08
Abstract: 

Objectives Indigenous people in Canada are not only over-represented among the homeless population but their pathways to homelessness may differ from those of non-Indigenous people. This study investigated the history and current status of Indigenous and non-Indigenous people experiencing homelessness and mental illness. We hypothesised that compared with non-Indigenous people, those who are Indigenous would demonstrate histories of displacement earlier in life, higher rates of trauma and self-medication with alcohol and other substances.

Design and setting Retrospective data were collected from a sample recruited through referral from diverse social and health agencies in Winnipeg and Vancouver.

Participants Eligibility included being 19 years or older, current mental disorder and homelessness.

Measures Data were collected via interviews, using questionnaires, on sociodemographics (eg, age, ethnicity, education), mental illness, substance use, physical health, service use and quality of life. Univariate and multivariable models were used to model the association between Indigenous ethnicity and dependent variables.

Results A total of 1010 people met the inclusion criteria, of whom 439 self-identified as Indigenous. In adjusted models, Indigenous ethnicity was independently associated with being homeless at a younger age, having a lifetime duration of homelessness longer than 3 years, post-traumatic stress disorder, less severe mental disorder, alcohol dependence, more severe substance use in the past month and infectious disease. Indigenous participants were also nearly twice as likely as others (47% vs 25%) to have children younger than 18 years.

Conclusions Among Canadians who are homeless and mentally ill, those who are Indigenous have distinct histories and current needs that are consistent with the legacy of colonisation. Responses to Indigenous homelessness must be developed within the context of reconciliation between Indigenous and non-Indigenous Canadians, addressing trauma, substance use and family separations.

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Association of Methadone Treatment With Substance-Related Hospital Admissions Among a Population in Canada With a History of Criminal Convictions

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2019-03-15
Abstract: 

Importance  People with criminal histories experience high rates of opioid dependence and are frequent users of acute health care services. It is unclear whether methadone adherence prevents hospitalizations.

Objective  To compare hospital admissions during medicated and nonmedicated methadone periods.

Design, Setting, and Participants  A retrospective cohort study involving linked population-level administrative data among individuals in British Columbia, Canada, with provincial justice contacts (n= 250 884) and who filled a methadone prescription between April 1, 2001, and March 31, 2015. Participants were followed from the date of first dispensed methadone prescription until censoring (date of death, or March 31, 2015). Data analysis was conducted from May 1 to August 31, 2018.

Exposures  Methadone treatment was divided into medicated (methadone was dispensed) and nonmedicated (methadone was not dispensed) periods and analyzed as a time-varying exposure.

Main Outcome and Measures  Adjusted hazard ratios (aHRs) of acute hospitalizations for any cause and cause-specific (substance use disorder [SUD], non–substance-related mental disorders [NSMDs], and medical diagnoses [MEDs]) were estimated using multivariable Cox proportional hazards regression.

Results  A total of 11 401 people (mean [SD] age, 34.9 [9.4] years; 8230 [72.2%] men) met inclusion criteria and were followed up for a total of 69 279.3 person-years. During a median follow-up time of 5.5 years (interquartile range, 2.8-9.1 years), there were 19 160 acute hospital admissions. Dispensed methadone was associated with a 50% lower rate of hospitalization for any cause (aHR, 0.50; 95% CI, 0.46-0.53) during the first 2 years (≤2.0 years) following methadone initiation, demonstrating significantly lower rates of admission for SUD (aHR, 0.32; 95% CI, 0.27-0.38), NSMD (aHR, 0.41; 95% CI, 0.34-0.50), and MED (aHR, 0.57; 95% CI, 0.52-0.62). As duration of time increased (2.1 to ≤5.0 years; 5.1 to ≤10.0 years), methadone was associated with a significant but smaller magnitude of effect: SUD (aHR, 0.43; 95% CI, 0.36-0.52; aHR, 0.47; 95% CI, 0.37-0.61), NSMD (aHR, 0.51; 95% CI, 0.41-0.64; aHR, 0.60; 95% CI, 0.47-0.78), and MED (aHR, 0.71; 95% CI, 0.65-0.77; aHR, 0.85; 95% CI, 0.76-0.95).

Conclusions and Relevance  In this study, methadone was associated with a lower rate of hospitalization among a large cohort of Canadian individuals with histories of convictions and prevalent concurrent health and social needs. Practices to improve methadone adherence are warranted.

 

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The Adherence Gap: A Longitudinal Examination of Men's and Women's Antiretroviral Therapy Adherence in British Columbia, 2000-2014

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

Objective: The aim of this study was to observe the effect of sex on attaining optimaladherence to combination antiretroviral therapy (cART) longitudinally while controllingfor known adherence confounders – IDU and ethnicity.Design: Using the population-based HAART Observational Medical Evaluation andResearch cohort, data were collected from HIV-positive adults, aged at least 19 years,receiving cART in British Columbia, Canada, with data collected between 2000 and2014. cART adherence was assessed using pharmacy refill data. The proportion ofparticipants reaching optimal (95%) adherence by sex was compared per 6-monthperiod from initiation of therapy onward. Generalized linear mixed models with logisticregression examined the effect of sex on cART adherence.Results: Among 4534 individuals followed for a median of 65.9 months (interquartilerange: 37.0–103.2), 904 (19.9%) were women, 589 (13.0%) were Indigenous, and1603 (35.4%) had a history of IDU. A significantly lower proportion of women relativeto men were optimally adherent overall (57.0 vs. 77.1%; P<0.001) and in covariateanalyses. In adjusted analyses, female sex remained independently associated withsuboptimal adherence overall (adjusted odds ratio: 0.55; 95% confidence interval:0.48–0.63).Conclusion: Women living with HIV had significantly lower cART adherence ratesthen men across a 14-year period overall, and by subgroup. Targeted research isrequired to identify barriers to adherence among women living with HIV to tailorwomen-centered HIV care and treatment support services.

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Who is in the Near Market for Bicycle Sharing? Identifying Current, Potential, and Unlikely Users of a Public Bicycle Share Program in Vancouver, Canada

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2018-11-29
Abstract: 

Background: Public bicycle share programs in many cities are used by a small segment of the population. To better understand the market for public bicycle share, this study examined the socio-demographic and transportation characteristics of current, potential, and unlikely users of a public bicycle share program and identified specific motivators and deterrents to public bicycle share use. 

Methods: We used cross-sectional data from a 2017 Vancouver public bicycle share (Mobi by Shaw Go) member survey (n = 1272) and a 2017 population-based survey of Vancouver residents (n = 792). We categorized non-users from the population survey as either potential or unlikely users based on their stated interest in using public bicycle share within the next year. We used descriptive statistics to compare the demographic and transportation characteristics of current users to non-users, and multiple logistic regression to compare the profiles of potential and unlikely users. 

Results: Public bicycle share users in Vancouver tended to be male, employed, and have higher educations and incomes as compared to non-users, and were more likely to use active modes of transportation. The vast majority of non-users (74%) thought the public bicycle share program was a good idea for Vancouver. Of the non-users, 23% were identified as potential users. Potential users tended to be younger, have lower incomes, and were more likely to use public transit for their main mode of transportation, as compared to current and unlikely users. The most common motivators among potential users related to health benefits, not owning a bicycle, and stations near their home or destination. The deterrents among unlikely users were a preference for riding their own bicycle, perceived inconvenience compared to other modes, bad weather, and traffic. Cost was a deterrent to one-fifth of unlikely users, notable given they tended to have lower incomes than current users. 

Conclusion: Findings can help inform targeted marketing and outreach to increase public bicycle share uptake in the population. 

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Maternal Obesity Alters Uterine NK Activity Through a Functional KIR2DL1/S1 Imbalance

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2018-03-13
Abstract: 

In pregnancy, uterine natural killer cells (uNK) play essential roles in coordinating uterine angiogenesis, blood vessel remodeling and promoting maternal tolerance to fetal tissue. Deviances from a normal uterine microenvironment are thought to modify uNK function(s) by limiting their ability to establish a healthy pregnancy. While maternal obesity has become a major health concern due to associations with adverse effects on fetal and maternal health, our understanding into how obesity contributes to poor pregnancy disorders is unknown. Given the importance of uNK in pregnancy, this study examines the impact of obesity on uNK function in women in early pregnancy. We identify that uNK from obese women show a greater propensity for cellular activation, but this difference does not translate into increased effector killing potential. Instead, uNK from obese women express an altered repertoire of natural killer receptors, including an imbalance in inhibitory KIR2DL1 and activating KIR2DS1 receptors that favors HLA-C2-directed uNK activation. Notably, we show that obesity-related KIR2DS1 skewing potentiates TNFα production upon receptor crosslinking. Together, these findings suggest that maternal obesity modifies uNK activity by altering the response toward HLA-C2 antigen and KIR2DL1/2DS1-controlled TNFα release. Furthermore, this work identifies alterations in uNK function resulting from maternal obesity that may impact early developmental processes important in pregnancy health.

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Maternal Obesity Drives Functional Alterations in Uterine NK Cells

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2016-07-21
Abstract: 

Over one-fifth of North American women of childbearing age are obese, putting these women at risk for a variety of detrimental chronic diseases. In addition, obesity increases the risk for developing major complications during pregnancy. The mechanisms by which obesity contributes to pregnancy complications and loss remain unknown. Increasing evidence indicates that obesity results in major changes to adipose tissue immune cell composition and function; whether or not obesity also affects immune function in the uterus has not been explored. Here we investigated the effect of obesity on uterine natural killer (uNK) cells, which are essential for uterine artery remodeling and placental development. Using a cohort of obese or lean women, we found that obesity led to a significant reduction in uNK cell numbers accompanied with impaired uterine artery remodeling. uNK cells isolated from obese women had altered expression of genes and pathways associated with extracellular matrix remodeling and growth factor signaling. Specifically, uNK cells were hyper-responsive to PDGF, resulting in overexpression of decorin. Functionally, decorin strongly inhibited placental development by limiting trophoblast survival. Together, these findings establish a potentially new link between obesity and poor pregnancy outcomes, and indicate that obesity-driven changes to uterine-resident immune cells critically impair placental development.

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Impacts of Bicycle Infrastructure in Mid-Sized Cities (IBIMS): protocol for a natural experiment study in three Canadian cities

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2018-01-21
Abstract: 

Introduction: Bicycling is promoted as a transportation and population health strategy globally. Yet bicycling has low uptake in North America (1%–2% of trips) compared with European bicycling cities (15%–40% of trips) and shows marked sex and age trends. Safety concerns due to collisions with motor vehicles are primary barriers.  To attract the broader population to bicycling, many cities are making investments in bicycle infrastructure. These interventions hold promise for improving population health given the potential for increased physical activity and improved safety, but such outcomes have been largely unstudied. In 2016, the City of Victoria, Canada, committed to build a connected network of infrastructure that separates bicycles from motor vehicles, designed to attract people of ‘all ages and abilities’ to bicycling.  This natural experiment study examines the impacts of the City of Victoria’s investment in a bicycle network on active travel and safety outcomes. The specific objectives are to (1) estimate changes in active travel, perceived safety and bicycle safety incidents; (2) analyse spatial inequities in access to bicycle infrastructure and safety incidents; and (3) assess health-related economic benefits.  Methods and analysis: The study is in three Canadian cities (intervention: Victoria; comparison: Kelowna, Halifax). We will administer population-based surveys in 2016, 2018 and 2021 (1000 people/city). The primary outcome is the proportion of people reporting bicycling. Secondary outcomes are perceived safety and bicycle safety incidents. Spatial analyses will compare the distribution of bicycle infrastructure and bicycle safety incidents across neighbourhoods and across time. We will also calculate the economic benefits of bicycling using WHO’s Health Economic Assessment Tool.  Ethics and dissemination: This study received approval from the Simon Fraser University Office of Research Ethics (study no. 2016s0401). Findings will be disseminated via a website, presentations to stakeholders, at academic conferences and through peer-reviewed journal articles

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Evaluation of the Impact of a Public Bicycle Share Program on Population Bicycling in Vancouver, BC

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

Public bicycle share programs have been implemented in cities around the world to encourage bicycling. However, there are limited evaluations of the impact of these programs on bicycling at the population level. This study examined the impact of a public bicycle share program on bicycling amongst residents of Vancouver, BC. Using an online panel, we surveyed a population-based sample of Vancouver residents three times: prior to the implementation of the public bicycle share program (T0, October 2015, n=1111); in the early phase of implementation (T1, October 2016, n=995); and one-year post implementation (T2, October 2017, n=966). We used difference in differences estimation to assess whether there was an increase in bicycling amongst those living and/or working in close proximity (≤500 m) to Vancouver's Mobi by Shaw Go public bicycle share program, compared to those living and working outside this area. Results suggest that only living or only working inside the bicycle share service area was not associated with increases in bicycling at T1 or T2 relative to those outside the service area. Both living and working inside the bicycle share service area was associated with increases in bicycling at T1 (OR: 2.26, 95% CI: 1.07, 4.80), however not at T2 (OR: 1.37, 95% CI: 0.67, 2.83). These findings indicate that the implementation of a public bicycle share program may have a greater effect on bicycling for residents who both live and work within the service area, although this effect may not be sustained over time. 

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