Doctor of Philosophy in Rehabilitation Sciences (PhD)
Wildfires, air pollution, and COVID-19: Individual and community resilience towards social and environmental disruption
Dissertations completed in 2010 or later are listed below. Please note that there is a 6-12 month delay to add the latest dissertations.
Background: Patients with chronic obstructive pulmonary disease (COPD) are known to have an increased risk of ischemic heart disease. Persistently elevated resting heart rate and arterial stiffness, two common clinical manifestations in COPD, are known determinants of myocardial ischemia as well as predictors of cardiovascular events. Controversies exist on the effect of pulmonary rehabilitation on these ischemic heart disease risk factors. No study has explored the effect of pulmonary rehabilitation on the resting heart rate - arterial stiffness relationship in COPD.Objectives and Methods: The overall objectives of this dissertation were to provide a comprehensive investigation of the resting heart rate and arterial stiffness in patients with COPD, and explore the impact of pulmonary rehabilitation on their relationship in this population. We describe the association between resting heart rate and prior myocardial infarction in patients with chronic lung disease attending pulmonary rehabilitation (Chapter 2). We test the reliability of resting heart rate and arterial stiffness measurements in COPD patients (Chapters 3 and 4). We determine the association between resting heart rate and arterial stiffness (Chapter 5), and explore the potential beneficial effects of standard pulmonary rehabilitation on resting heart rate and/or arterial stiffness in COPD (Chapter 6).Summary of findings: We showed that an elevated resting heart rate is a potential indicator of prior myocardial infarction in patients with chronic lung disease (Chapter 2). Resting heart rate and arterial stiffness measurements have excellent and substantial reliability, respectively, under a standardized procedure in COPD patients (Chapters 3 and 4). The association between resting heart rate and arterial stiffness in control subjects is not present in patients with COPD (Chapter 5). Standard pulmonary rehabilitation in COPD reduces arterial stiffness, but not resting heart rate, and does not impact the resting heart rate - arterial stiffness relationship (Chapter 6).Conclusions: This dissertation provides new knowledge on resting heart rate and arterial stiffness, as well as on the potential beneficial effects of pulmonary rehabilitation on these two ischemic heart disease risk factors in COPD patients.
Theses completed in 2010 or later are listed below. Please note that there is a 6-12 month delay to add the latest theses.
This project was in response to the Carrier Sekani Family Services (CSFS) Community Advisory Committee’s request that, in addition to lung function testing, the research team assess indoor air quality to confirm factors that affect lung health.Specific Aims: The goal of this study was to measure the prevalence of inhaled pollutants that First Nations people living in northern BC are exposed to from indoor residential places and to estimate the association between levels of inhaled pollutants and 1) respiratory symptoms and 2) lung function.Research Methodology: This study was conducted in partnership with CSFS which has provided health and wellness services to its member Nations since 1990. Real-time air and dust samples were taken from both randomly sampled and volunteered residences. Measurements of carbon monoxide (CO), carbon dioxide (CO₂), temperature, and relative humidity were taken using a Q-Trak monitoring tool. Particle counts were measured with the Kanomax monitor. Settled dust samples were collected and analyzed to assess the presence and amount of inhalable bioactive molecules including antigens and endotoxins. Respiratory symptoms such as cough, wheeze, phlegm, and shortness of breath were evaluated by a self-report questionnaire. Direct measurements of lung function were assessed using pre-and post-bronchodilator spirometry. The analytical procedure was performed according to the laboratory standard operating procedures. Statistical analysis was conducted with SPSS version 28.0.0 and Microsoft Excel 2013.Results: Bacterial endotoxins were detected in all households. Forty-six percent of households had bacterial endotoxins ≥100 EU/mg. Felis domesticus (Fel d1) ng/mg had the highest levels of all detectable antigens with a mean and standard deviation (SD) of 2.16 ng (10.25) and was detected in sixty-six percent of the households. Particulate matter (PM) (0.3 µm, 0.5 µm, 1 µm) was associated with self-reported cough symptom. None of the other indoor air pollutants were associated with self-reported respiratory symptoms nor lung function. Conclusion: Given the small sample size, there is a need for more case-control, cohort, and cross-sectional studies, including children and a more comprehensive age range, to properly understand the effects of indoor air pollutants and other health outcomes in this community.
Background: Acute exacerbations of COPD (AECOPD) are episodes of acute deterioration in airway function and respiratory symptoms. Physical activity and exercise are important components in the recovery of patients from exacerbation. AECOPD-Mob is an evidence-based clinical decision-making tool on best practice for safe and effective exercise for hospitalized AECOPD patients. In our lab, we developed four formats of the tool (the original paper version, a Learner module, a Smartphone app and a traditional Inservice) and evaluated their usability by physical therapists (PTs) and registered nurses (RNs) working in acute care hospitals.Methods: In this study, we have examined the insights of 17 PTs and 3 RNs about the usability and intended use of the AECOPD-Mob formats. The participants were provided with access to the four AECOPD-Mob formats, completed an Evidence-Based-Practice (EBP) Barriers Questionnaire, the Post Study System Usability Questionnaire (PSSUQ) and participated in focus groups to share their thoughts and experiences.Results: We have found that the health care providers (HCPs), PTs and RNs, were satisfied with the usability learner module but were less satisfied with the usability of the Smartphone app. In addition, we originated four key themes from the focus groups: ‘HCPs’ knowledge gaps’, ‘HCPs preferences’, ’Tool quality and usability’ and ‘Improvement suggestions’ and found that the overall preferred version the AECOPD-Mob tool was the original paper version. The learner module and the Inservice were seen as interchangeable and provided necessary information, while the learner module had the benefit of being accessible at any time and, the Inservice had the benefit of better enabled discussion amongst colleagues. The app was considered challenging to use at the bedside, but the content was very favorable. Interestingly, we have found that RNs had a preference for more concise information, while PTs where looking for more broad information in the formats which give more of an overview. Conclusion: We found that PTs and RNs found the AECOPD-Mob paper version to be the easiest and most versatile format. There were concerns about using an App in a hospital setting.Future research should investigate the impact of AECOPD-Mob on patient outcomes.
Pulmonary rehabilitation (PR) is a comprehensive intervention of self-management education and exercise training that improves quality of life, exercise tolerance, symptoms of dyspnea, and reduces the risk of hospitalization in patients living with chronic respiratory diseases such as chronic obstructive pulmonary disease, asthma, lung cancer, and interstitial lung disease. Despite the proven benefit of pulmonary rehabilitation, recent studies have found notable inconsistencies in its organization and delivery. Inconsistencies within clinical practice are likely to affect the quality in the delivery of pulmonary rehabilitation. Quality indicators (QIs) are tools similar to a checklist that can potentially remediate these concerns. While other jurisdictions have created quality indicators for pulmonary rehabilitation programs, their methodological approach to developing these quality indicators is questionable. This study developed 56 quality indicators with a rigorous approach using a modified RAND Appropriateness Method. A panel comprising twelve PR healthcare professionals and stakeholders was created to create a list of QIs. The panel rated each indicator based on four criteria (importance, scientific soundness, reliability, and feasibility) and listed which indicator they believed could determine a quality pulmonary rehabilitation program. This study recommends that the 56 QIs, based upon consensus, be used for operationalizing the evaluation and auditing of PR programs as well as for establishing clinical benchmarks.
Introduction: Chronic Obstructive Pulmonary Disease (COPD) symptoms of dyspnea, exercise intolerance, and reduced health related quality of life are best treated with pulmonary rehabilitation (PR). Despite benefits, transportation, availability of PR programs, and social support barriers limit PR access. Telerehabilitation (TR) may provide the solution by utilizing pulse oximetry to monitor patient oxygen saturation (SpO₂) and heart rate (HR), along with measures of exercise intensity to ensure patient safety during home-based, unsupervised rehabilitation exercise. Study Purpose: To test the validity and reliability of a smartphone system called LungFIT in measuring heart rate, oxygen saturation, and distance in a healthy population. The LungFIT’s functionality was also assessed. Methods: Functionality of the LungFIT was assessed by a time-to-complete test and the adapted Mobile Phone Usability Questionnaire (MPUQ). SpO₂ and HR measurements by 3 different LungFIT probes (Nonin, Masimo, and LionsGate Technologies) were evaluated during 5-minute cycle ergometry (50 watts at 60-70 revolutions/minute) and treadmill walking tests (3km/hr). Both tests were repeated 3 times. Distance measurements were assessed by outdoor walking tests of a 1 city block course. Results: SpO₂ measurements were valid with mean biases ranging between -0.93% and 0.88% and limits of agreement no greater than ±3.78% over the 3 LungFIT probes. The Masimo probe had the smallest mean biases ranging from 0.18% to 0.74% and mean limits of agreement ranging from ±1.94% (±0.93% 95% confidence interval) to ±2.79% (±1.34% 95% confidence interval). All probes had moderate to good SpO₂ measurement reliability (ICCs between 0.65-0.87) with the Masimo probe performing the best (all ICCs ≥ 0.82). During exercise, HR measurements were invalid (mean limits of agreement > 10.00 beats/min), but reliable (ICCs between 0.87-0.97). Time-to-complete assessments found no software issues, but revealed 4 instances of navigation or setup issues. The MPUQ showed ease of use despite lack of interface appeal. Conclusion: During exercise, the 3 LungFIT probes were reliable in measuring SpO₂ and HR, but only valid in measuring SpO₂. Overall, the Masimo probe was the most valid and reliable of the 3 probes tested. Future LungFIT prototypes will improve user interface and accuracy of distance measurements.
Background: Physical activity may reduce mortality risk in advanced chronic lung disease by optimizing functional capacity, which is a major prognostic indicator in lung transplantation candidates. There is uncertainty as to the optimal method to measure physical activity in this patient population. We assessed different commercially-available physical activity measurement techniques (flex heart rate monitoring (FHR); pedometry; tri-axial accelerometry; and multi-sensor technology) by investigating their agreement with indirect calorimetry (IC) in adult lung disease patients (chronic obstructive pulmonary disease (COPD), interstitial lung disease (ILD), and cystic fibrosis (CF)) with advanced pulmonary impairment. Methods: This is a cross-sectional method comparison study conducted on two separate days. We recruited consecutive COPD, ILD, and CF patients with physician diagnosis of advanced pulmonary impairment. On day one, participants performed cardiopulmonary exercise testing until exhaustion with measurements of oxygen uptake (VO₂) and heart rate (HR) collected. On day two, subjects had their VO₂ and HR measured during standardized resting and sub-maximal activity. Simultaneous VO₂ and HR measures from both days were used to develop individual regressions for FHR-derived energy expenditure (EE). We then simultaneously measured each subject’s EE using a variety of index measures of physical activity and IC during standardized “free-living” type activities and varying intensities of sub-maximal cycle exercise. Results: In a sample of eight participants (CF, n=5; COPD, n=2; ILD, n=1), Flex HR methods using submaximal (FMSUB) and CPET-derived (FMCPX) calibrations showed the best agreement and interchangeability with IC during free-living and cycling activities compared to the SenseWear (SW) and ActiCal (AC) devices as evidenced by lower mean differences with IC and widths of limit of agreement (LOA) + 95% confidence interval (CI). For the secondary index methods assessed, the Tractivity and DigiWalker devices significantly over and underestimated IC EE respectively (p0.05) over the entire protocol. Conclusion: Our study found that the Flex HR method for EE estimation had the lowest bias and variability during free-living activities and exercise. EE estimation using Flex HR methods may be potentially useful clinical tools to ensure metabolic energy balance and activity monitoring in advanced lung disease groups.