Health Sciences - Theses, Dissertations, and other Required Graduate Degree Essays

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Epidemiological evaluations of methadone adherence in opioid dependent offenders: Implications for public health and public safety

Author: 
Date created: 
2019-08-13
Abstract: 

Background: Opioid use is associated with elevated rates of morbidity and mortality and has a significant impact on public health and public order. Justice involved individuals are disproportionately affected by opioid related harms but effective interventions are underutilized. Methadone maintenance treatment is the best researched and mostly widely implemented pharmacotherapy option for the treatment of opioid dependence. Despite its demonstrated efficacy in general populations, few studies have examined its effectiveness among patients with criminal justice histories and complex health and social challenges. This thesis aims to address the deficits in existing extant literature through three unique research studies described herein. Methods: All studies were conducted using a retrospective cohort design involving linked population-level administrative data. Participants comprised a cohort of individuals from British Columbia, Canada with histories of convictions and who filled a methadone prescription. Three independent analyses estimated the effect of methadone on crime, mortality and hospitalization. Methadone was divided into medicated (methadone was dispensed) and nonmedicated (methadone was not dispensed) periods and analyzed as a time-varying exposure. Cox regression was used in all three analyses and hazard ratios with 95% confidence intervals were reported as an effect size. In all instances additional subgroup and sensitivity analyses were performed. Results: Over a mean follow-up time of eight years, findings from the sample (n=14, 530) revealed a significant association between dispensed methadone and lower rates of violent and non-violent crime; all-cause and cause-specific mortality; and any-cause hospitalization (n=11, 401) even after controlling for a number of covariates. Findings for crime and hospitalization analyses demonstrated the magnitude of protective effect for methadone was greatest during the initial years following methadone treatment initiation but decayed in periods exceeding a decade. Subgroup and sensitivity analyses demonstrated a similar pattern of results. Conclusions: Adherence to methadone is associated with lower rates of opioid related harms among justice involved patients with opioid dependence. Results consistently point to the need for increased access to methadone and higher rates of adherence for offenders and similarly marginalized groups. Implementation of evidence-based policies and programs are required to improve adherence and promote recovery in this vulnerable population.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Julian Somers
Department: 
Health Sciences: Faculty of Health Sciences
Thesis type: 
(Thesis) Ph.D.

Improving patients’ understanding of their rights under British Columbia’s Mental Health Act

Author: 
Date created: 
2019-07-02
Abstract: 

In a 2011 survey of mental health patients in BC, 43% of respondents who had been involuntarily hospitalized said that their rights under the Mental Health Act were not explained to them in a way they could understand. One possible reason for this lack of understanding is that the document used to give rights information to involuntary patients, the statutory Form 13, may not be an effective communication tool. Another possible reason is that the rights-information process doesn’t meet patients’ information needs. Using a qualitative approach anchored in a transformative research paradigm, which seeks to redress power differences by involving the community of interest in designing and implementing solutions, I aimed to identify key features of a patient-centred rights-information process. First, I user tested Form 13 with people who had experienced involuntary hospitalization. The main findings were that the form’s content was unclear and had an intimidating and disempowering tone. Armed with this feedback, I coordinated a patient-oriented research team to develop a new suite of rights-communication tools to supplement Form 13. I user tested the tools with people who had experienced involuntary hospitalization. Participants found the suite of tools friendlier to use compared with Form 13. They appreciated that the many formats within the suite would accommodate different communication preferences and would give patients several opportunities to learn about their rights. I did a thematic analysis of the full set of user-testing interviews to learn more about involuntary patients’ experiences with the rights-information process. A key theme was that patients wanted more transparency and open communication about every aspect of their hospitalization. They also wanted clinicians to foster a culture where patients could feel safe talking about rights. The uncertainty from a lack of information exacerbated participants’ mental distress and made some fearful of hospitalization. A better understanding of what they could do under the legislation and how much they could participate in treatment decisions would reduce feelings of powerlessness and could help involuntary patients engage in their own recovery.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Diego Silva
Department: 
Health Sciences: Faculty of Health Sciences
Thesis type: 
(Thesis) Ph.D.

What is a First Nation person's wellness journey?

Author: 
Date created: 
2019-06-20
Abstract: 

To address the health disparities for First Nation people it is important to understand what their wellness journey encompasses and how primary care services can support their individual journeys. Current health care structures focus on illness and what is wrong with an individual. It is coming to light more that the four aspects of a human being are important to promote wellness throughout an individual’s life journey. Historically, First Nation wellness encompassed spiritual, emotional, mental and physical components of each individual. The analysis of information, gathered through observation and interview methods in this research project, utilized the First Nation Health Authority’s First Nation Perspective of Wellness as a framework to ensure all components of an individual were honoured. Honouring the information shared by each of the research participants, their voices are heard through direct participant quotes. Participants related their mental wellness journeys, what worked and what didn’t, who they considered important in their journeys and times in their lives where they identified a change occurring. Instrumental to this was the support provided by their community. This research project was supported by the community of Seabird Island and portrays how their current health and cultural programs and services are supporting their client’s wellness journeys. Key priorities identified from observations of community cultural workshops and semi-structured interviews include health services considering each individual’s needs, access to culturally safe services, the importance of belonging and purpose in life, as well as how spirituality and gratitude support an individual’s wellness journeys.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Malcolm Steinberg
Department: 
Health Sciences: Faculty of Health Sciences
Thesis type: 
(Thesis) M.Sc.

Temporal and geographic variation in aeroallergen measurements across four Canadian cities from 2008-2012

Date created: 
2019-03-11
Abstract: 

Fungal spores and pollen from trees, grasses, and weeds are associated with outdoor environmental allergies in Canada. These aeroallergens typically have a distinct temporal pattern across geographical regions. This study describes seasonal and geographic variation in aeroallergens from 2008-2012 in the Canadian cities of Vancouver, Edmonton, Winnipeg, and Toronto. The study period and study locations were chosen to characterize the potential aeroallergen exposures of participants in the Canadian Healthy Infant Longitudinal Development (CHILD) birth cohort. Seasonal exposures in Vancouver were the longest for every group of aeroallergens, except grasses. Vancouver was also the highest for the trees pollen. Total fungal spore concentrations were higher in Edmonton, Winnipeg, and Toronto than in Vancouver. The differences recorded in this study across geographical regions may be significant for the CHILD participants if they lead to distinct and clinically important windows of exposure for infant immune response and subsequent differential risk of allergenic disease.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Timothy Takaro
Department: 
Health Sciences: Faculty of Health Sciences
Thesis type: 
(Thesis) M.Sc.

Impact of natural HIV-1 Nef alleles and polymorphisms on SERINC3/5 downregulation

Author: 
Date created: 
2019-04-25
Abstract: 

HIV-1 Nef is a multifunctional accessory protein required for efficient viral pathogenesis. It was recently identified that the serine incorporators (SERINC) 3 and 5 are host restriction factors that decrease the infectivity of HIV-1 when incorporated into newly formed virions. However, Nef counteracts these effects by downregulating SERINC from the cell surface. Currently, there lacks a comprehensive study investigating the impact of primary Nef alleles on SERINC downregulation, as most studies to date utilize lab-adapted or reference HIV strains. In this thesis, I characterized and compared SERINC downregulation from >400 Nef alleles isolated from patients with distinct clinical outcomes and subtypes. I found that primary Nef alleles displayed a dynamic range of SERINC downregulation abilities, thus allowing naturally-occurring polymorphisms that modulate this activity to be identified. In addition, I found that Nef alleles isolated from patients with better clinical outcomes had a poorer ability to counteract SERINC, suggesting that variation in this activity may contribute to differences in HIV-1 pathogenesis.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Mark Brockman
Department: 
Health Sciences: Faculty of Health Sciences
Thesis type: 
(Thesis) M.Sc.

Associations between prenatal exposure to air pollutants and Autism Spectrum Disorder: A population-based cohort study in Metro Vancouver, Canada

Author: 
Date created: 
2018-08-01
Abstract: 

The etiology of autism spectrum disorder (ASD) is poorly understood, but emerging evidence suggests that environmental factors may have a larger contributing role to the risk of ASD than previously thought. Recent studies suggest an association between air pollution and ASD. We conducted a retrospective, population-based cohort study of nearly all births in Metro Vancouver, Canada, from 2004–2009 to evaluate prenatal exposures to PM2.5, NO, and NO2 as modifiable environmental risk factors for ASD. Children were diagnosed with ASD using a standardized assessment of Autism Diagnostic Interview-Revised and Autism Diagnostic Observation Schedule. Using temporally adjusted land use regression models, we estimated monthly mean ambient air pollution exposures during pregnancy for each person at their home address. We observed positive associations between air pollutant exposures and increased risk of ASD, especially for males, in a population-based cohort living in an area with relatively low levels of air pollution.

Document type: 
Thesis
Senior supervisor: 
Meghan Winters
Bruce Lanphear
Department: 
Health Sciences: Faculty of Health Sciences
Thesis type: 
(Thesis) M.Sc.

Medical returnees: Somali Canadians seeking psychosocial and spiritual healing in East Africa

Date created: 
2018-04-26
Abstract: 

Background: The refugee experience has been associated with increased rates of psychosocial challenges. At the same time, evidence suggests that those who resettle in Western countries underutilize Western mental health services. The reluctance of refugees to use mental health services has been attributed to barriers to accessing services such as language, complexity of the health system, and differing explanatory models of illness. The same is true for Somali refugees in Western countries. Studies suggest that Somali refugees prefer spiritual healing for psychosocial illness and that some return to East Africa for healing. However, little is known about the mental health of the Somali community in Canada and the services they utilize for psychosocial problems. Objectives: In conducting original ethnographic study, I aimed to understand the psychosocial challenges faced by Somali Canadians, their health seeking behaviors, and their access and barriers to psychosocial services in Canada. Because some have sought psychosocial services at international destinations, I conducted fieldwork in Kenya to provide new evidence on the little-known transnational spiritual healing systems popular among diasporic Somalis. Methods: Ethnographic fieldwork and in-depth interviews were utilized. Thirty-seven in-depth interviews of about an hour each were undertaken in Canada and Kenya. Fieldwork focused on visiting spiritual and cultural healing centers in Nairobi for three to four hours each. Results: The findings show that some families struggle with childhood autism and youth substance use, while others deal with psychosocial and spiritual distress such schizophrenia, depression, and Jinn. The preferred treatment approaches ranged from holistic biomedical treatments combined with spiritual healing to only cultural and spiritual healing. Discussion: This study reveals important findings regarding psychosocial and substance use problems among Somali Canadians. I discuss psychosocial illnesses, challenges with accessing Canadian healthcare services, the role of spiritual healers, and seeking culturally appropriate services in East Africa. I further discuss substance use problems among Somali Canadian youth, the lack of culturally appropriate services in Canada, and the emergence of transnational cultural recovery programs in Kenya. I also highlight challenges associated with transnational rehabilitation programs.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Marina Morrow
Department: 
Health Sciences: Faculty of Health Sciences
Thesis type: 
(Thesis) Ph.D.

Factors Affecting the Use of Midwifery Services in Remote Nepal

Author: 
Peer reviewed: 
No, item is not peer reviewed.
Date created: 
2019-10-08
Abstract: 

Tens of thousands of mothers and hundreds of thousands of newborns die each year or have birth injuries. Families living in remote mountainous areas of Nepal are geographically marginalized, and women often deliver without skilled assistance. Human resources are few and often not trained to the level that international professional organizations recommend. Although the government has established birthing centers in communities in eastern Nepal’s remote, mountainous region of lower Solukhumbu, they are not fully utilized. This study of birthing in a remote area of Nepal examined factors associated with access to skilled birth attendants from both a health systems perspective and from the perspectives of mothers and community members. A concurrent, embedded, mixed methods study investigated mothers’, maternity staff and community members’ experiences with birth through semi-structured interviews. The skills of attending nurses, and the enabling factors such as infrastructure, equipment, and supplies in three levels of maternity facilities were examined through two surveys. Participant observation and field notes were additional methods used. Distance and cost were barriers for many women and lack of birth preparedness contributed to delays in reaching a facility if problems occurred. Although communities believed that health facilities save lives, some women preferred home births, citing institutional barriers arising from outdated and unnecessary obstetrical practices, and lack of choices for women. A shortage of skilled human resources and lack of adequate life-saving supplies and medications were found. Lack of infrastructure resulted in difficulty providing care and referrals. Skilled birth attendants were found to have gaps in life-saving skills. Infrastructure and supplies were inadequate in birthing centers. Improvements in quality of care to maintain cultural safety within birthing institutions require respect for women’s preferences, including birth companions and spiritual healers when requested. Frequent focussed midwifery skills refreshers are needed to improve ability to provide skilled and respectful care. Implementing a fully trained midwifery cohort in rural areas would be a longer term goal.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Craig Janes
Department: 
Health Sciences: Faculty of Health Sciences
Thesis type: 
(Thesis) Ph.D.

Resources to support Indigenous reproductive health and justice in Toronto: A respondent-driven sampling study

Date created: 
2018-11-09
Abstract: 

In Canada, the reproductive health and rights of Indigenous women, two-spirit, trans, and gender diverse people are threatened by the complex nature of historic and ongoing colonialism. In the face of widespread oppression, however, Indigenous women, two-spirit, trans, and gender diverse people find ways to achieve wellness. To provide novel statistical information about Indigenous reproductive health, this Master’s thesis takes a strengths-based approach to understanding causes of wellness in a cohort of urban Indigenous women, two-spirit, trans, and gender diverse people of reproductive age (n=323). Through a community-based research partnership with the Seventh Generation Midwives of Toronto and the Well Living House, this study uses secondary data collected with respondent-driven sampling (RDS) methods for the community-driven health survey Our Health Counts Toronto. By drawing on community perspectives and Indigenous reproductive justice theories, we hypothesized that four different resources enhance wellness: (1) relationship to land; (2) traditional foods; (3) cultural connectedness; and, (4) Indigenous programs and services. Logistic regression modelling revealed that relationships to land, traditional foods, and Indigenous programs and services were statistically significant to wellness. This study may aid policy makers and service providers in promoting equitable reproductive health care for Indigenous peoples in Toronto and other Canadian cities. Furthermore, this study demonstrates the applicability of critical Indigenous theories and activism to the fields of population health and epidemiology.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Nicole Berry
Scott Venners
Department: 
Health Sciences: Faculty of Health Sciences
Thesis type: 
(Thesis) M.Sc.

Nonmedical prescription opioid initiation, ongoing use, and related overdose among people who use drugs in Vancouver, Canada

Author: 
Date created: 
2018-12-12
Abstract: 

Background: The prevalence and harms associated with nonmedical prescription opioid use (NMPOU) have risen in Canada, and the prevailing policy response has restricted the supply of prescription opioids (POs) and promoted more responsible patient behaviour. Despite this quick action to address NMPOU, there are key knowledge gaps related to NMPOU initiation, ongoing use, and associated harms among people who use illegal street drugs (PWUD). Objectives: (i) conduct a systematized review of the extant literature related to NMPOU, (ii) identify the prevalence and correlates associated with NMPOU-related initiation trajectories and engaging in recent NMPOU, and (iii) investigate the impact of acquiring POs from physicians for the purposes of NMPOU. Methods: Multiple databases were systematically searched for extant literature on NMPOU. For the empirical studies, data were derived from the Vancouver Drug Users Study, which is an open prospective cohort study of youth and adult PWUD in Vancouver, Canada. Utilizing cross-sectional and longitudinal regression techniques and various sub-samples, I assessed the relationship between various risk factors and the following outcomes: engaging in recent NMPOU, initiating NMPOU before illegal street drugs (vs. after), initiating NMPOU using a physician prescription, and recent non-fatal overdose. Results: The review found some consistent indicators of risk related to NMPOU and gaps in knowledge related to NMPOU among hidden populations. In the empirical analyses, engaging in NMPOU was associated with a higher risk profile regardless of age and sex, and initiating NMPOU before illegal street drugs was also linked with a higher risk profile when compared with those who never engaged in NMPOU. Initiating NMPOU with a physician prescription was not a key indicator of high-intensity substance use or socio-structural vulnerability and acquiring POs using a physician prescription was not associated with recent non-fatal overdose. Conclusions: The results indicate that engaging in NMPOU is associated with a higher risk profile; however, NMPOU-related initiation trajectories and acquisition source do not appear to be a meaningful target for policy solutions or interventions. This dissertation provides some evidence for developing unique strategies to address ongoing NMPOU among younger and older PWUD that includes opioid agonist treatment and income generation opportunities.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Will Small
Robert Hogg
Department: 
Health Sciences: Faculty of Health Sciences
Thesis type: 
(Thesis) Ph.D.