Jeffrey A Johnson

University of Alberta, Edmonton, Alberta, Canada

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Publications (245)824.13 Total impact

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    ABSTRACT: Seasonality in health outcomes has long been recognized in conditions such as colds and flu's. This study sought to determine if hospitalizations of acute complications of type 1 diabetes vary by month and season. We performed an observational study of national administrative health data. Hospitalizations for acute complications in adults (age ≥ 18 years old) with type 1 diabetes were identified using ICD-10 CA codes between 2004 and 2010. Monthly and seasonal counts per year were determined for the study period. For each acute complication, a ratio of the number of observed hospitalizations divided by the expected number of hospitalizations was calculated for each month and season per year, adjusting for varied lengths of month, season, and year. There were a total of 21,568 hospitalizations for diabetic ketoacidosis and 5,349 hospitalizations for hypoglycemia in the study period. December demonstrated higher than expected hospitalizations for diabetic ketoacidosis and March demonstrated higher than expected hospitalizations for hypoglycemia. There did not appear to be variation for either diabetic ketoacidosis or hypoglycemia hospitalizations by season. This study suggests temporal variation in hospitalizations for diabetic ketoacidosis and hypoglycemia, and therefore signals important times of patient vulnerability. Potential mechanisms underlying this pattern warrant further examination. Prevention strategies and resources for patients with type 1 diabetes may need to be increased at specific times during the year. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    Journal of Diabetes 08/2015; DOI:10.1111/1753-0407.12336 · 2.35 Impact Factor
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    ABSTRACT: The Healthy Eating and Active Living for Diabetes in Primary Care Networks (HEALD) intervention proved effective in increasing daily physical activity among people with type 2 diabetes in 4 community-based primary care networks (PCNs) in Alberta. Here, we contextualize its effectiveness by describing implementation fidelity and PCN staff's perceptions of its success in improving diabetes management. We used the Reach, Effectiveness, Adoption, Implementation and Maintenance (RE-AIM) framework to evaluate the HEALD intervention. Qualitative methods used to collect data related to the RE-AIM dimensions of implementation and effectiveness included interviews with PCN staff (n=24), research team reflections (n=4) and systematic documentation. We used content analysis, and data were imported into and managed using Nvivo 10. HEALD was implemented as intended with adequate fidelity across all 4 PCNs. Identified implementation facilitators included appropriate human resources, the training provided, ongoing support, the provision of space and the simplicity of the intervention. However, PCN staff reported varying opinions regarding its potential for improving diabetes management among patients. Rationales for their views included intervention "dose" inadequacy; that the quality of usual care for people with diabetes was already good; patients were already managing their diabetes well; and the potential for cointervention. Recommended improvements to HEALD included increasing the dose of the intervention, expanding it to other modes of exercise and incorporating a medical clearance process. Based on the high degree of fidelity, the demonstrated effectiveness of HEALD in improving physical activity among patients was a result of sound implementation of an efficacious intervention. Increasing the dose of HEALD could result in additional improvements for patients. Copyright © 2015 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.
    08/2015; DOI:10.1016/j.jcjd.2015.05.003
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    ABSTRACT: OBJECTIVE: To examine the prevalence and predictors of foot disease, self-care and clinical monitoring in adults with type 2 diabetes in Alberta, Canada. METHOD: Baseline data from a prospective cohort of adults with type 2 diabetes were used. Assessment of foot disease included self-reported peripheral neuropathy, peripheral vasculopathy, foot or leg ulcer/infection or gangrene/amputation. Foot self-care was assessed using the Summary of Diabetes Self-Care Activities, and clinical monitoring using patients' reports of having feet checked for lesions or sensory loss. RESULTS: The mean age of respondents (N=2040) was 64 (SD 10.7) years; 45% were female, and 91% were Caucasian. Peripheral neuropathy was reported by 18% of the respondents, peripheral vasculopathy by 28%, ulcer/infection by 6% and gangrene/amputation by 1.4%. Only 14% of respondents performed foot self-care behaviours ≥6 days per week, and only 41% and 34% had their feet clinically checked for lesions or sensory loss, respectively. Predictors of foot disease included longer duration of diabetes, smoking, depressive symptoms, low self-efficacy and a history of cardiovascular diseases. Predictors of good self-care included older age, female sex, longer duration of diabetes and no report of hyperlipidemia. Predictors of clinical monitoring included female sex, current smoking, residing in urban areas, longer duration of diabetes, and histories of heart disease or hyperlipidemia. CONCLUSIONS: Peripheral neuropathy and vasculopathy were the most common reported foot problems in this population. Foot self-care is generally infrequent, and clinical monitoring is performed for less than half of these patients, with significant variations by patient demographics and clinical presentation.
    Canadian Journal of Diabetes 08/2015; · 0.46 Impact Factor
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    ABSTRACT: To better understand the factors that affect care and outcomes in patients with type 2 diabetes, we developed the prospective Alberta's Caring for Diabetes (ABCD) cohort to collect, monitor and analyze data concerning several sociodemographic, behavioural, psychosocial, clinical and physiological factors that might influence diabetes care and outcomes. We recruited 2040 individuals with type 2 diabetes through primary care networks, diabetes clinics and public advertisements. Data are being collected through self-administered surveys, including standardized measures of health status and self-care behaviours, and will eventually be linked to laboratory and administrative healthcare data and other novel databases. The average age of respondents was 64.4 years (SD=10.7); 45% were female, and 91% were white, with average duration of diabetes of 12 years (SD=10.0). The majority (76%) were physically inactive, and 10% were smokers. Most (88%) reported 2 or more chronic conditions in addition to diabetes, and 18% screened positively for depressive symptoms. The majority (92%) consented to future linkage with administrative data. Based on the literature and comparison with other surveys, the cohort appeared to fairly represent the general Alberta population with diabetes. The ABCD cohort will serve as the basis for explorations of the multidimensional and dynamic nature of diabetes care and complications. These data will contribute to broader scientific literature and will also help to identify local benchmarks and targets for intervention strategies, helping to guide policies and resource allocation related to the care and management of patients with type 2 diabetes in Alberta, Canada. Copyright © 2015 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.
    Canadian Journal of Diabetes 08/2015; DOI:10.1016/j.jcjd.2015.05.005 · 0.46 Impact Factor
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    ABSTRACT: To examine the prevalence and predictors of foot disease, self-care and clinical monitoring in adults with type 2 diabetes in Alberta, Canada. Baseline data from a prospective cohort of adults with type 2 diabetes were used. Assessment of foot disease included self-reported peripheral neuropathy, peripheral vasculopathy, foot or leg ulcer/infection or gangrene/amputation. Foot self-care was assessed using the Summary of Diabetes Self-Care Activities, and clinical monitoring using patients' reports of having feet checked for lesions or sensory loss. The mean age of respondents (N=2040) was 64 (SD 10.7) years; 45% were female, and 91% were Caucasian. Peripheral neuropathy was reported by 18% of the respondents, peripheral vasculopathy by 28%, ulcer/infection by 6% and gangrene/amputation by 1.4%. Only 14% of respondents performed foot self-care behaviours ≥6 days per week, and only 41% and 34% had their feet clinically checked for lesions or sensory loss, respectively. Predictors of foot disease included longer duration of diabetes, smoking, depressive symptoms, low self-efficacy and a history of cardiovascular diseases. Predictors of good self-care included older age, female sex, longer duration of diabetes and no report of hyperlipidemia. Predictors of clinical monitoring included female sex, current smoking, residing in urban areas, longer duration of diabetes, and histories of heart disease or hyperlipidemia. Peripheral neuropathy and vasculopathy were the most common reported foot problems in this population. Foot self-care is generally infrequent, and clinical monitoring is performed for less than half of these patients, with significant variations by patient demographics and clinical presentation. Copyright © 2015 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.
    Canadian Journal of Diabetes 08/2015; DOI:10.1016/j.jcjd.2015.05.006 · 0.46 Impact Factor
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    Fatima Al Sayah · Ana Mladenovic · Kathryn Gaebel · Feng Xie · Jeffrey A Johnson
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    ABSTRACT: The EuroQol Valuation Technology (EQ-VT) uses traditional time trade-off (tTTO) for health states better than dead and lead-time TTO (LT-TTO) for states worse than dead to elicit a value (-1.0 to +1.0) for each health state. In the Canadian EQ-5D-5L Valuation study which used the EQVT platform, we observed an unexpected peak in frequency of "0" values and few negative values, particularly in the range of 0 to -0.5. To better understand this finding, we sought to explore respondents' thought processes while valuing a health state, and their understanding of the tTTO and LT-TTO exercises. Qualitative semi-structured interviews were conducted with EQVT task respondents. Questions focused on valuations of health states as: (a) Same as dead in tTTO, (b) Worse than dead in tTTO but changed to same as dead in LT-TTO, (c) Worse than dead in LT-TTO, and (d) Worse than dead in LT-TTO with trading off all 10 years. Data were analyzed using content and thematic analysis. Mean age of participants (N = 70) was 40 ± 18.1 years, 60 % female, and 76 % Caucasian. Participants provided similar reasons for valuing a health state same as or worse than dead. Many participants expressed confusion about worse than dead valuations, distinction between same as and worse than dead, and the transition from tTTO to LT-TTO. A few indicated that the addition of 10 years of full health in the LT-TTO influenced their valuations. The transition from tTTO to LT-TTO in the EQVT was confusing to participants, whereby some health state valuations around this transition appeared to be arbitrary.
    Quality of Life Research 07/2015; DOI:10.1007/s11136-015-1073-9 · 2.86 Impact Factor
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    ABSTRACT: We evaluated the implementation of an efficacious collaborative care model for patients with diabetes and depression in a controlled trial in 4 community-based primary care networks (PCNs) in Alberta, Canada. Similar to previous randomized trials, the nurse care manager-led TeamCare intervention demonstrated statistically significant improvements in depressive symptoms compared with usual care. We contextualized TeamCare's effectiveness by describing implementation fidelity at the organizational and patient levels. We used the Reach, Effectiveness, Adoption, Implementation and Maintenance (RE-AIM) framework to evaluate TeamCare. Qualitative methods used to collect data regarding the RE-AIM dimensions of Implementation and Effectiveness included interviews with PCN staff and specialists (n=36), research team reflections (n=4) and systematic documentation. We used content analysis, and Nvivo 10 for data management. TeamCare was implemented as intended but with suboptimal fidelity. Deviations from the model included limited degrees of collaborative care practised within the PCNs, including varying physician participation, limited comfort in practising collaborative care and discontinuity of care managers. Despite suboptimal fidelity, respondents identified several implementation facilitators at the organizational level: training, ongoing implementation support, professional and personal qualities of the care manager and pre-existing relationships. Without knowledge of the effectiveness of the intervention in our controlled trial, respondents anticipated improved patient outcomes due to the main intervention components, including active patient follow up, specialist consultation and treat-to-target principles. Despite suboptimal implementation in Alberta's primary care context, TeamCare resulted in improved outcomes similar to those demonstrated in previous randomized trials. A stronger culture of collaborative care would likely have yielded greater implementation fidelity and possibly better outcomes. Copyright © 2015 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.
    07/2015; DOI:10.1016/j.jcjd.2015.05.004
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    ABSTRACT: Although there have been tremendous advances in diabetes care, including the development of efficacious interventions, there remain considerable challenges in translating these advances into practice. Four primary care networks (PCNs) in Alberta implemented 2 quality-improvement interventions focused on lifestyle and depression as part of the Alberta's Caring for Diabetes (ABCD) project. We used the reach, effectiveness, adoption, implementation and maintenance (RE-AIM) framework to evaluate adoption of the quality-improvement interventions in the PCN setting. We undertook semistructured interviews with PCN staff (n=24); systematic documentation (e.g. field notes) and formal reflections by the research team (n=4). Content analysis was used to interrogate the data. The Ready? Set? Go! construct summarizes our findings well. We observed that the participating PCNs were in a favourable position to adopt the 2 interventions successfully. We implemented strategies to promote adoption (Ready), and respondents reported prioritization and willingness to initiate the interventions based on positive indicators (Set). Regardless, the interplay of organizational stability, leadership support, existing physician culture and organizational context influenced the overall degree of adoption of the interventions across the PCNs (Go). Our findings suggest that implementation of quality-improvement interventions into settings similar to the PCNs we studied will have the greatest likelihood of success when there is priority alignment, genuine and sustained leadership support and an innovative organizational culture. However, the stability of organizations may affect the degree to which staff can adopt quality-improvement interventions successfully, so organizational stability should be assessed on an ongoing basis. Copyright © 2015 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.
    07/2015; DOI:10.1016/j.jcjd.2015.05.002
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    ABSTRACT: Patient registries are considered an important foundation of chronic disease management, and diabetes patient registries are associated with better processes and outcomes of care. The purpose of this article is to describe the development and use of registries in the Alberta's Caring for Diabetes (ABCD) project to identify and reach target populations for quality-improvement interventions in the primary care setting. We applied the reach, effectiveness, adoption, implementation and maintenance (RE-AIM) framework and expanded the definition of reach beyond the individual (i.e. patient) level to include the ability to identify target populations at an organizational level. To characterize reach and the implementation of registries, semistructured interviews were conducted with key informants, and a usual-care checklist was compiled for each participating Primary Care Network (PCN). Content analysis was used to analyze qualitative data. Using registries to identify and recruit participants for the ABCD interventions proved challenging. The quality of the registries depended on whether physicians granted PCN access to patient lists, the strategies used in development, the reliability of diagnostic information and the data elements collected. In addition, once a diabetes registry was developed, there was limited ability to update it. Proactive management of chronic diseases like diabetes requires the ability to reach targeted patients at the population level. We observed several challenges to the development and application of patient registries. Given the importance of valid registries, strong collaborations and novel strategies that involve policy-makers, PCNs and providers are needed to help find solutions to improve registry quality and resolve maintenance issues. Copyright © 2015 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.
    07/2015; DOI:10.1016/j.jcjd.2015.05.001
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    ABSTRACT: Epidemiological research has posited a 'healthy user' bias in patients receiving influenza vaccination; thus we sought to evaluate potential healthy-user attributes and their associations with influenza vaccination. Between 2011 and 2013, adults with type 2 diabetes were enrolled in a prospective cohort in Alberta, Canada. Information collected included sociodemographics, diabetes-related data (e.g., duration, complications), health behaviors (e.g., smoking status), functional health status, and satisfaction with healthcare. Data were collected by a mailed, self-administered survey. Multivariable logistic regression analyses were used to identify potential healthy-user attributes independently associated with influenza vaccination. From a cohort of 2040 patients, 1287 (63%) reported receiving the influenza vaccine in the previous year. Average age of the cohort was 64 years (standard deviation 11) and 55% were male. In multivariable analysis, attributes independently associated with influenza vaccination included receiving preventive medications: aspirin (64% vs 44%; adjusted odds ratio, aOR 1.65, 95% CI 1.34-2.04); blood pressure medications (76% vs 56%; aOR 1.36, 95% CI 1.07-1.71); and cholesterol-lowering medications (74% vs 53%; aOR 1.50, 95% CI 1.19-1.89), as well as having a healthcare professional check feet for lesions (47% vs 31%; aOR 1.39, 95% CI 1.12-1.74). Additional covariates independently associated with influenza vaccination included: age over 65 years, respiratory disease, the number of additional comorbidities, and higher ratings of healthcare experience. Vaccinated diabetic patients exhibit many postulated attributes of 'healthy users', which has implications for the interpretation of epidemiological studies of influenza vaccine effectiveness, as well as targeting future vaccination campaigns. Copyright © 2015. Published by Elsevier Ltd.
    Vaccine 06/2015; 33(30). DOI:10.1016/j.vaccine.2015.05.047 · 3.49 Impact Factor
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    ABSTRACT: To identify which activities produced a significant improvement in blood pressure control in patients with type 2 diabetes when pharmacists were added to primary care teams. This prespecified, secondary analysis evaluated medication management data from a randomized controlled trial. The primary outcome was a change in treatment, defined as addition, dosage increase, or switching of an antihypertensive medication during the 1-year study period. The secondary outcome was a change in antihypertensive medication adherence using the medication possession ratio (MPR). The 200 evaluable trial patients had a mean age of 59 (SD, 11) years, 44% were men, and mean blood pressure was 130 (SD, 16)/74 (SD, 10) mm Hg at baseline. Treatment changes occurred in 45 (42%) of 107 patients in the intervention group and 24 (26%) of 93 patients in the control group (RR, 1.63; 95% CI, 1.08-2.46). Addition of a new medication was the most common type of change, occurring in 34 (32%) patients in the intervention group and 17 (18%) patients in the control group (P = 0.029). Adherence to antihypertensive medication was high at baseline (MPR, 93%). Although medication adherence improved in the intervention group (MPR, 97%) and declined in the control group (MPR, 91%), the difference between groups was not significant (P = 0.21). The observed improvement in blood pressure control when pharmacists were added to primary care teams was likely achieved through antihypertensive treatment changes and not through improvements in antihypertensive medication adherence.
    Journal of the American Pharmacists Association 04/2015; 55(3):e301-e304. DOI:10.1331/JAPhA.2015.14225
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    ABSTRACT: To the Editor: We thank Frans Pouwer for his comments on our study [1] exploring adherence to glucose-lowering drugs following a cancer diagnosis among individuals with diabetes [2]. Our findings revealed that there was a significant drop in the medication possession ratio at the time of cancer diagnosis, with the largest drops among patients with stage IV disease and gastrointestinal or pulmonary cancers. In his letter, Pouwer describes two potential mechanisms that could explain these results [1].As Pouwer indicates, weight loss has been associated with improvements in beta cell function and insulin sensitivity among individuals with diabetes. As a result, glucose levels decline, HbA1c values improve and less glucose-lowering drug treatment may be required to obtain optimal metabolic control. While weight loss is common among cancer patients, especially among those with gastrointestinal, lung or advanced cancer, as described by Pouwer, the impact of weight loss on metabolic control a ...
    Diabetologia 04/2015; 58(6). DOI:10.1007/s00125-015-3578-8 · 6.88 Impact Factor
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    Jongnam Hwang · Christopher Rudnisky · Sarah Bowen · Jeffrey A Johnson
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    ABSTRACT: To examine the association between socioeconomic factors and ophthalmic care services/visual impairment among patients with diabetes. Data from the Survey on Living with Chronic Disease in Canada (SLCDC)-Diabetes Component 2011 were used. A cross-sectional, nationally representative sample of patients with diabetes weighted to represent the civilian, noninstitutionalized Canadian population with self-reported type II diabetes. Socioeconomic factors were classified into predictive factors, need, and non-need factors. Factors associated with the ophthalmic care utilization and visual impairment were assessed using logistic regression models, weighted for the SLCDC sampling strategy. Among all patients with type II diabetes, factors associated with increased eye screening were: (i) discussion of diabetic complications with health professionals (odds ratio [OR] 2.02, 95% CI 1.28-3.19); (ii) having private insurance (OR 3.23, 95% CI 2.21-4.73); and (iii) duration of diabetes longer than 10 years (OR 1.53, 95% CI 1.04-2.25). Among asymptomatic patients (those who reported having no visual impairment), patients with lower income had 40% decreased odds of having eye screening services compared with those with higher income (OR 0.60, 95% CI 0.37-0.98). Among all patients with type II diabetes, visual impairment was more likely in females (OR 1.53, 95% CI 1.12-2.09), older patients (OR 18.12, 95% CI 6.63-49.51), and those with poor self-rated health (OR 3.10, 95% CI 1.62-5.96). Our study found that interactions between health professionals and patients, as well as having private health insurance, were the main factors associated with ophthalmic resource utilization, whereas age, sex, duration of diabetes, and self-rated health were associated with visual impairment in patients with type II diabetes. Copyright © 2015 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.
    Canadian Journal of Ophthalmology 04/2015; 50(2):119-126. DOI:10.1016/j.jcjo.2014.11.014 · 1.30 Impact Factor
  • Fatima Al Sayah · Sumit R Majumdar · Leonard E Egede · Jeffrey A Johnson
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    ABSTRACT: Inadequate health literacy has been associated with poorer health behaviors and outcomes in individuals with diabetes or depression. This study was conducted to examine the associations between inadequate health literacy and behavioral and cardiometabolic parameters in individuals with type 2 diabetes and to explore whether these associations are affected by concurrent depression. The authors used cross-sectional data from a study of 343 predominantly African Americans with type 2 diabetes. Inadequate health literacy was significantly and modestly associated with diabetes knowledge (r = -0.34) but weakly associated with self-efficacy (r = 0.16) and depressive symptoms (r = 0.24). In multivariate regression models, there were no associations between health literacy and A1c, blood pressure, or body mass index or control of any of these parameters. There was no evidence that depression was an effect-modifier of the associations between health literacy and outcomes. Although inadequate health literacy was modestly associated with worse knowledge and weakly associated with self-efficacy, it was not associated with any of the cardiometabolic parameters the authors studied. Because this study showed no association between health literacy and behavioral and cardiometabolic outcomes, it is unseemly and premature to embark on trials or controlled interventions to improve health literacy for the purposes of improving patient-related outcomes in diabetes.
    Journal of Health Communication 03/2015; 20(5):1-8. DOI:10.1080/10810730.2015.1012235 · 1.61 Impact Factor
  • Fatima Al Sayah · Sumit R Majumdar · Jeffrey A Johnson
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    ABSTRACT: To examine the relationship of inadequate health literacy (HL) with changes in depressive symptoms, health-related quality of life and cardiometabolic outcomes in patients with type 2 diabetes mellitus recently screened positive for depression. Secondary analysis of data from a clinical trial (N=154) that compared a collaborative team care model and enhanced usual care for primary care for patients with type 2 diabetes and depression. The exposure of interest was inadequate HL, defined as a total summative score of 9 or more on the 3 brief screening questions. Outcomes of interest were differences in the changes in depressive symptoms (Patient Health Questionnaire-9 (PHQ-9) at 12 months, health-related quality of life (short-form health survey 12 [SF-12]) and European Quality of Life-5 Dimensions questionnaire (EQ-5D), glycemic control (A1C), low-density lipoprotein cholesterol and systolic blood pressure. The average age of patients was 58 years; 56% were women and were predominantly white. Only a small proportion (n=24; 16%) had inadequate HL. In adjusted random effects models, there were no statistically significant or clinically important differences in all outcomes between the HL groups. The between-group differences in change over 1 year were -0.55 points for PHQ-9; 0.76 points for physical and 0.56 points for mental summaries of the SF-12; 0.03 points for EQ-5D; -0.17 for A1C; -0.08 mmol/L for low-density lipoprotein; and -1.94 mm Hg for systolic blood pressure. Among primary care patients with type 2 diabetes who had been screened recently as being positive for depression, it is unlikely that HL impacts health outcomes over 1 year. Copyright © 2015 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.
    03/2015; DOI:10.1016/j.jcjd.2014.11.005
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    ABSTRACT: Adherence to glucose-lowering drug (GLD) treatment regimens is crucial for metabolic control and improving prognosis. Because a diagnosis of cancer might have an impact on adherence to medication, this study explored changes in adherence to GLDs following a cancer diagnosis. All new users of GLDs between 1998 and 2011 who lived in the Eindhoven Cancer Registry-PHARMO Database Network catchment area were selected. Those with a primary cancer diagnosis during follow-up were considered cases and matched with eligible controls without cancer during follow-up. Medication possession ratio (MPR) was used as indicator for medication adherence. Segmented linear auto-regression analysis with interrupted time series was used to assess changes in MPR for cases compared with controls (i.e. overall trend) due to (any) cancer diagnosis and specific cancer types. From the 52,228 GLD users selected, 3,281 cases with cancer and 12,891 controls without cancer during follow-up were included in the study. In our analyses, before cancer diagnosis the MPR increased by 0.10% per month (95% CI 0.10, 0.10). Besides a significant drop in MPR at the time of cancer diagnosis of -6.3% (95% CI -6.5, -6.0), there was an ongoing, yet lower, monthly decline in MPR (-0.20%; 95% CI -0.21, -0.20) after cancer diagnosis. The largest drops in MPR at the time of cancer diagnosis, in the range of 11-15%, were seen among patients with stage IV disease and gastrointestinal or pulmonary cancers. Our findings indicate a clear decline in adherence to GLD treatment regimens following a cancer diagnosis. The reason for the decline in MPR needs to be further elucidated.
    Diabetologia 02/2015; 58(5). DOI:10.1007/s00125-015-3497-8 · 6.88 Impact Factor
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    ABSTRACT: Frailty is a multidimensional syndrome characterized by loss of physiologic reserve that gives rise to vulnerability to poor outcomes. We aimed to examine the association between frailty and long-term health-related quality-of-life among survivors of critical illness. Prospective multicenter observational cohort study. ICUs in six hospitals from across Alberta, Canada. Four hundred twenty-one critically ill patients who were 50 years or older. None. Frailty was operationalized by a score of more than 4 on the Clinical Frailty Scale. Health-related quality-of-life was measured by the EuroQol Health Questionnaire and Short-Form 12 Physical and Mental Component Scores at 6 and 12 months. Multiple logistic and linear regression with generalized estimating equations was used to explore the association between frailty and health-related quality-of-life. In total, frailty was diagnosed in 33% (95% CI, 28-38). Frail patients were older, had more comorbidities, and higher illness severity. EuroQol-visual analogue scale scores were lower for frail compared with not frail patients at 6 months (52.2 ± 22.5 vs 64.6 ± 19.4; p < 0.001) and 12 months (54.4 ± 23.1 vs 68.0 ± 17.8; p < 0.001). Frail patients reported greater problems with mobility (71% vs 45%; odds ratio, 3.1 [1.6-6.1]; p = 0.001), self-care (49% vs 15%; odds ratio, 5.8 [2.9-11.7]; p < 0.001), usual activities (80% vs 52%; odds ratio, 3.9 [1.8-8.2]; p < 0.001), pain/discomfort (68% vs 47%; odds ratio, 2.0 [1.1-3.8]; p = 0.03), and anxiety/depression (51% vs 27%; odds ratio, 2.8 [1.5-5.3]; p = 0.001) compared with not frail patients. Frail patients described lower health-related quality-of-life on both physical component score (34.7 ± 7.8 vs 37.8 ± 6.7; p = 0.012) and mental component score (33.8 ± 7.0 vs 38.6 ± 7.7; p < 0.001) at 12 months. Frail survivors of critical illness experienced greater impairment in health-related quality-of-life, functional dependence, and disability compared with those not frail. The systematic assessment of frailty may assist in better informing patients and families on the complexities of survivorship and recovery.
    Critical Care Medicine 01/2015; 43(5). DOI:10.1097/CCM.0000000000000860 · 6.15 Impact Factor
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    ABSTRACT: Our purpose was to measure the effect of non-benefit drug use on observed associations between exposure and outcome, thereby documenting an empirical example of the potential magnitude of biases introduced when exposure status is misclassified from a restrictive drug coverage policy. New users of antidiabetic agents were identified with a 1-year washout period between January 1, 1995, and December 31, 2005, in Saskatchewan, Canada, and were followed until December 31, 2008. Within this population-based cohort, persons were classified as users of benefit or non-benefit thiazolidinediones (TZDs) according to their first prescription record between January 1, 2006, and December 31, 2006 (non-benefit prescription records were not captured before 2006). An intention-to-treat approach was used to categorize TZD exposure over time. We evaluated the potential bias introduced by drug exposure misclassification by evaluating bootstrapped differences in hazard ratio (HR) estimates of all-cause hospitalization or death between users and nonusers of TZDs obtained from analyses that contained complete drug use (non-benefit and benefit drug use) versus benefit drug use only (non-benefit drug use was misclassified as unexposed). All analyses were replicated within the same cohort of new users of antidiabetic agents for clopidogrel and β-blocker (bisoprolol or carvedilol) users versus nonusers because these agents were also subject to exposure misclassification from non-benefit drug use during the period of the study. Among 27,333 new users of antidiabetic agents, we identified 5759 TZD users (28% non-benefit) and 21,574 nonusers of TZDs. The crude HR for hospitalization or death among TZD users versus nonusers was higher in a database that contained benefit-only prescriptions than in a database that contained all prescriptions (HR = 1.11 [95% CI, 1.05-1.18] vs HR = 0.99 [95% CI, 0.94-1.04]). However, the differences in HRs after adjustment for demographic characteristics, health care utilization, comorbidities, and medications suggested minimal bias was introduced when TZD exposure was misclassified in the benefit-only database (adjusted HR [aHR] = 1.04 [95% CI. 0.98-1.10] vs aHR = 0.99 [95% CI, 0.94-1.04]; bootstrapped aHR difference = +0.05 [95% CI, 0.02-0.08]). Minimal differences in aHRs were also observed within analyses of clopidogrel (1551 users [24% non-benefit]; bootstrapped aHR difference = +0.01 [95% CI, -0.04 to 0.06]) and β-blocker users (351 users [42% non-benefit]; bootstrapped aHR difference = +0.06 [95% CI, -0.09 to 0.20]) versus nonusers. Although patient characteristics and outcomes differed between users of non-benefit and benefit drugs, misclassification of drug exposure did not meaningfully bias estimates of all-cause mortality and hospitalization after covariate adjustment in our study. Copyright © 2015 Elsevier HS Journals, Inc. All rights reserved.
    Clinical Therapeutics 01/2015; 37(3). DOI:10.1016/j.clinthera.2014.12.014 · 2.59 Impact Factor
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    ABSTRACT: Randomized controlled trials are considered the "gold standard" for scientific rigor in the assessment of benefits and harms of interventions in healthcare. They may not always be feasible, however, when evaluating quality improvement interventions in real-world healthcare settings. Non-randomized controlled trials (NCTs) are designed to answer questions of effectiveness of interventions in routine clinical practice to inform a decision or process. The on-off NCT design is a relatively new design where participant allocation is by alternation. In alternation, eligible patients are allocated to the intervention "on" or control "off " groups in time series dependent sequential clusters. We used two quality improvement studies undertaken in a Canadian primary care setting to illustrate the features of the on-off design. We also explored the perceptions and experiences of healthcare providers tasked with implementing the on-off study design. The on-off design successfully allocated patients to intervention and control groups. Imbalances between baseline variables were attributed to chance, with no detectable biases. However, healthcare providers' perspectives and experiences with the design in practice reveal some conflict. Specifically, providers described the process of allocating patients to the off group as unethical and immoral, feeling it was in direct conflict with their professional principle of providing care for all. The degree of dissatisfaction seemed exacerbated by: 1) the patient population involved (e.g., patient population viewed as high-risk (e.g., depressed or suicidal)), 2) conducting assessments without taking action (e.g., administering the PHQ-9 and not acting on the results), and 3) the (non-blinded) allocation process. Alternation, as in the on-off design, is a credible form of allocation. The conflict reported by healthcare providers in implementing the design, while not unique to the on-off design, may be alleviated by greater emphasis on the purpose of the research and having research assistants allocate patients and collect data instead of the healthcare providers implementing the trial. In addition, consultation with front-line staff implementing the trials with an on-off design on appropriateness to the setting (e.g., alignment with professional values and the patient population served) may be beneficial. Health Eating and Active Living with Diabetes: ClinicalTrials.gov identifier: NCT00991380 Date registered: 7 October 2009. Controlled trial of a collaborative primary care team model for patients with diabetes and depression: Clintrials.gov Identifier: NCT01328639 Date registered: 30 March 2011.
    Trials 01/2015; 16(1):375. DOI:10.1186/s13063-015-0904-x · 2.12 Impact Factor
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    ABSTRACT: The evidence on the association between pioglitazone use and bladder cancer is contradictory, with many studies subject to allocation bias. The aim of our study was to examine the effect of exposure to pioglitazone on bladder cancer risk internationally across several cohorts. The potential for allocation bias was minimised by focusing on the cumulative effect of pioglitazone as the primary endpoint using a time-dependent approach. Prescription, cancer and mortality data from people with type 2 diabetes were obtained from six populations across the world (British Columbia, Finland, Manchester, Rotterdam, Scotland and the UK Clinical Practice Research Datalink). A discrete time failure analysis using Poisson regression was applied separately to data from each centre to model the effect of cumulative drug exposure on bladder cancer incidence, with time-dependent adjustment for ever use of pioglitazone. These were then pooled using fixed and random effects meta-regression. Data were collated on 1.01 million persons over 5.9 million person-years. There were 3,248 cases of incident bladder cancer, with 117 exposed cases and a median follow-up duration of 4.0 to 7.4 years. Overall, there was no evidence for any association between cumulative exposure to pioglitazone and bladder cancer in men (rate ratio [RR] per 100 days of cumulative exposure, 1.01; 95% CI 0.97, 1.06) or women (RR 1.04; 95% CI 0.97, 1.11) after adjustment for age, calendar year, diabetes duration, smoking and any ever use of pioglitazone. No association was observed between rosiglitazone and bladder cancer in men (RR 1.01; 95% CI 0.98, 1.03) or women (RR 1.00; 95% CI 0.94, 1.07). The cumulative use of pioglitazone or rosiglitazone was not associated with the incidence of bladder cancer in this large, pooled multipopulation analysis.
    Diabetologia 12/2014; 58(3). DOI:10.1007/s00125-014-3456-9 · 6.88 Impact Factor

Publication Stats

7k Citations
824.13 Total Impact Points

Institutions

  • 1997–2015
    • University of Alberta
      • • School of Public Health
      • • Department of Public Health Sciences
      • • Department of Medicine
      • • Faculty of Pharmacy and Pharmaceutical Sciences
      Edmonton, Alberta, Canada
  • 2013
    • The Ottawa Hospital
      Ottawa, Ontario, Canada
    • TEC Edmonton
      Edmonton, Alberta, Canada
    • Athabasca University
      • Centre for Nursing and Health Studies
      Атабаска, Alberta, Canada
  • 2010
    • Statistics Canada
      • Division of Health Analysis
      Ottawa, Ontario, Canada
  • 2000–2008
    • Institute of Health Economics
      Edmonton, Alberta, Canada
  • 2007
    • University of Illinois at Chicago
      • Department of Pharmacy Administration
      Chicago, Illinois, United States
  • 2005
    • National Cancer Institute (USA)
      • Division of Cancer Control and Population Sciences
      Bethesda, MD, United States
    • Thomas Jefferson University
      Filadelfia, Pennsylvania, United States
    • The University of Western Ontario
      • Department of Medicine
      London, Ontario, Canada
  • 2003
    • University of Iowa
      Iowa City, Iowa, United States