Jacek A Kopec

University of British Columbia - Vancouver, Vancouver, British Columbia, Canada

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Publications (167)604.41 Total impact

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    ABSTRACT: To estimate the future direct cost of OA in Canada using a population-based health microsimulation model of osteoarthritis (POHEM-OA). We used administrative health data from the province of British Columbia (BC), Canada, a survey of a random sample of BC residents diagnosed with OA (Ministry of Health of BC data), Canadian Institute of Health Information (CIHI) cost data and literature estimates to populate a microsimulation model. Cost components associated with pharmacological and non-pharmacological treatments, total joint replacement surgery, as well as use of hospital resources and management of complications arising from the treatment of osteoarthritis were included. Future costs were then simulated using the POHEM-OA model to construct profiles for each adult Canadian. From 2010 to 2031, as the prevalence of OA is projected to increase from 13.8% to 18.6%, the total direct cost of OA is projected to increase from $2.9 billion to $7.6 billion, an almost 2.6-fold increase (in 2010 $CAD). From the highest to the lowest, the cost components that will constitute the total direct cost of OA in 2031 are hospitalization cost ($2.9 billion), outpatient services ($1.2 billion), alternative care and out-of-pocket cost categories ($1.2 billion), drugs ($1 billion), rehabilitation ($0.7 billion) and side-effect of drugs ($0.6 billion). Projecting the future trends in the cost of OA enables policy makers to anticipate the significant shifts in its distribution of burden in the future. Copyright © 2015. Published by Elsevier Ltd.
    Osteoarthritis and Cartilage 06/2015; DOI:10.1016/j.joca.2015.05.029 · 4.66 Impact Factor
  • Osteoarthritis and Cartilage 04/2015; 23:A170-A171. DOI:10.1016/j.joca.2015.02.938 · 4.66 Impact Factor
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    Osteoarthritis and Cartilage 04/2015; 23:A321-A322. DOI:10.1016/j.joca.2015.02.583 · 4.66 Impact Factor
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    ABSTRACT: Objectives. Our aim was to determine the risk of diabetes among osteoarthritis (OA) cases in a prospective longitudinal study. Methods. Administrative health records of 577,601 randomly selected individuals from British Columbia, Canada, from 1991 to 2009, were analyzed. OA and diabetes cases were identified by checking physician's visits and hospital records. From 1991 to 1996 we documented 19,143 existing OA cases and selected one non-OA individual matched by age, sex, and year of administrative records. Poisson regression and Cox proportional hazards models were fitted to estimate the effects after adjusting for available sociodemographic and medical factors. Results. At baseline, the mean age of OA cases was 61 years and 60.5% were women. Over 12 years of mean follow-up, the incidence rate (95% CI) of diabetes was 11.2 (10.90-11.50) per 1000 person years. Adjusted RRs (95% CI) for diabetes were 1.27 (1.15-1.41), 1.21 (1.08-1.35), 1.16 (1.04-1.28), and 0.99 (0.86-1.14) for younger women (age 20-64 years), older women (age ≥ 65 years), younger men, and older men, respectively. Conclusion. Younger adults and older women with OA have increased risks of developing diabetes compared to their age-sex matched non-OA counterparts. Further studies are needed to confirm these results and to elucidate the potential mechanisms.
    International Journal of Rheumatology 11/2014; 2014:620920. DOI:10.1155/2014/620920
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    ABSTRACT: Identifying persons with early rheumatoid arthritis (RA) is a major challenge. The role of the Internet in making decisions about seeking care has not been studied. We developed a method for early diagnosis and referral using the Arthritis Foundation's website. A person with less than 3 months of joint pain symptom who has not yet sought medical attention was screened. Prescreened persons are linked to a self-scoring questionnaire and get a "likelihood" of RA statement. If "likely," the person is offered a free evaluation and biomarker testing performed by Quest Diagnostics. The system available only to Massachusetts's residents yielded a small steady flow of screen-positive individuals. Over 21 months, 43,244 persons took the Arthritis Foundation website prescreening questionnaire; 196 were from Massachusetts and 60 took the self-scoring algorithm. Of the 48 who screened positive, 29 set up an appointment for a free evaluation, but six never came in. Twenty-four subjects were evaluated and diagnosed independently by three rheumatologists. One met the 1987 American College of Rheumatology (ACR) criteria for RA and two met the 2010 ACR/EULAR RA criteria. The 24 examined individuals were contacted at a minimum of 1 year and asked to redo the case-finding questionnaire and asked about their health resource utilization during the interval. Seventeen of the 24 subjects responded, and 10 had seen a health professional. Three of the 17 had a diagnosis of RA; all were on at least methotrexate. Internet case finding was useful in identifying new potential RA cases. The system's performance characteristics are theoretically limited only by the number of study sites available. However, the major barrier may be that seeing a health professional is not a priority for many individuals with early symptoms.
    Clinical Rheumatology 10/2014; 34(3). DOI:10.1007/s10067-014-2796-7 · 1.77 Impact Factor
  • International journal of radiation oncology, biology, physics 09/2014; 90(1):S4-S5. DOI:10.1016/j.ijrobp.2014.06.024 · 4.18 Impact Factor
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    ABSTRACT: Background Gestational Diabetes Mellitus (GDM) is a common health problem among pregnant women and may be associated with distress. Purpose The purpose of the study was to describe changes in patient-reported outcomes in women with GDM and identify factors associated with increased distress in these patients. Research Design The study was conducted in 205 women diagnosed with GDM. Study participants underwent a physical examination and completed a questionnaire two times during pregnancy. On average, the questionnaire was completed at 27 weeks of gestation at baseline and 36 weeks at follow-up. The questionnaire included socio-demographic and clinical variables, standardized patient-reported outcome measures, and questions about the impact of GDM on daily life, satisfaction with care, knowledge about GDM, and social and professional support. Our main outcome of interest was diabetes-related distress, measured by the Problem Areas in Diabetes (PAID) questionnaire. Data were analyzed using descriptive statistics and multivariable regression models. Results At baseline, 80 % of the women were satisfied with their diabetes care and 58 % said they managed their diabetes well. The proportion reporting little or no knowledge of GDM dropped from almost 50 % at baseline to 14 % at follow-up. However, the proportion reporting that GDM affected their social life increased from 26 to 35 %, and the proportion reporting interference with family life increased from 14 to 26 %. Insulin treatment, frequency of blood glucose measurements, lack of knowledge about GDM, and lack of support from family and health care providers were strongly and significantly associated with distress. Conclusion In women with GDM, intensified treatment and lack of informational and social support are associated with distress. These aspects of GDM care appear to be appropriate targets for future research and interventions aimed at reducing the level of distress in these patients.
    International Journal of Behavioral Medicine 08/2014; 22(2). DOI:10.1007/s12529-014-9428-0 · 2.63 Impact Factor
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    ABSTRACT: Objective. To evaluate the validity (accuracy) and reliability of 2 commonly used clinical methods, 1 indirect (lifts) and 1 direct (tape measure), for assessment of leg length discrepancy (LLD) in comparison to radiograph. Methods. Twenty subjects suspected of having LLD participated in this study. Two clinical methods, 1 direct using a tape measure and 1 indirect using lifts, were standardized and carried out by 4 examiners. Difference in height of the femoral heads on standing pelvic radiograph was measured and served as the gold standard. Results. The intraclass correlation coefficient assessing interobserver reliability was 0.737 for lifts and 0.477 for tape measure. The remainder of the analysis is based on the average of the measurements by the 4 examiners. Pearson correlation coefficients were 0.93 for the lifts and 0.75 for the tape measure method. Paired sample t tests showed difference in means of 2 mm (p = 0.051) for lifts and -5 mm (p = 0.007) for tape measure compared with radiograph. Sensitivity and specificity were 55% and 89% for lifts and 45% and 56% for tape measure, respectively, using > 5 mm as the definition for LLD. The wrong leg was identified as being shorter in 1 out of 20 subjects using lifts versus 7 out of 20 using tape measure. Conclusion. The indirect standing method of LLD measurement using lifts had superior validity, interobserver reliability, and specificity in comparison with radiograph over the direct supine method using tape measure. Both clinical methods underestimated LLD compared with radiograph.
    The Journal of Rheumatology 07/2014; 41(8). DOI:10.3899/jrheum.131089 · 3.17 Impact Factor
  • 69th Annual Meeting of the Canadian-Rheumatology-Association (CRA); 07/2014
  • 69th Annual Meeting of the Canadian-Rheumatology-Association (CRA); 07/2014
  • 69th Annual Meeting of the Canadian-Rheumatology-Association (CRA); 07/2014
  • Annals of the Rheumatic Diseases 06/2014; 73(Suppl 2):259-259. DOI:10.1136/annrheumdis-2014-eular.4840 · 10.38 Impact Factor
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    ABSTRACT: To calculate the incidence rates of osteoarthritis (OA) and to describe the changes in incidence using 18 years of administrative health records. We analyzed visits to health professionals and hospital admission records in a random sample (n = 640,000) from British Columbia, Canada, from 1991/1992 through 2008/2009. OA was defined in 2 ways: (1) at least 1 physician diagnosis or 1 hospital admission; and (2) at least 2 physician diagnoses in 2 years or 1 hospital admission. Crude and age-standardized rates were calculated, and the annual relative changes were estimated from the Poisson regression models. In 2008/2009, the overall crude incidence rate (95% CI) of OA using definition 1 was 14.6 (14.0-14.8); [12.5 (12.0-13.0) among men and 16.3 (15.8-16.8) among women] per 1000 person-years. The rates were lower by about 44% under definition 2. For the period 2000/2001-2008/2009, crude incidence rates based on definition 1 varied from 11.8 to 14.2 per 1000 person-years for men, and from 15.7 to 18.5 for women. Annually, on average, crude rates rose by about 2.5-3.3% for both men and women. The age-adjusted rates increased by 0.6-0.8% among men and showed no trend among women. Our study generated updated incidence rates of administrative OA for the Province of British Columbia. Physician-diagnosed overall incidence rates of OA varied with the case definitions used; however, trends were similar in both case definitions. Age-adjusted rates among men increased slightly during the period 2000/2001-2008/2009. These findings have implications for projecting future prevalence and costs of OA.
    The Journal of Rheumatology 04/2014; 41(6). DOI:10.3899/jrheum.131011 · 3.17 Impact Factor
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    ABSTRACT: Purpose To assess the association between subchondral sclerosis detected at baseline with MRI and cartilage loss over time in the same region of the knee in a cohort of subjects with knee pain. Methods 163 subjects with knee pain participated in a longitudinal study to assess knee osteoarthritis progression. Subjects received baseline knee radiographs as well as baseline and 3-year follow-up MRI examinations. Baseline subchondral sclerosis and bone marrow lesions (BMLs) were scored semiquantitatively on MRI in each region from 0 to 3. Cartilage morphology at baseline and follow-up was scored semiquantitatively from 0 to 4. The association between baseline subchondral sclerosis and cartilage loss in the same region of the knee was evaluated using logistic regression, adjusting the results for age, gender, body mass index, and the presence of concomitant BMLs. Results The prevalence of subchondral sclerosis detected by MRI in the regions of the knee varied between 1.6% (trochlea) and 17% (medial tibia). The occurrence of cartilage loss over time in regions varied between 6% (lateral tibia) and 13.1% (medial femur). The prevalence of radiographically-detected subchondral sclerosis in compartments varied from 2.9% (patellofemoral) to 14.2% (medial tibiofemoral). In logistic regression models, there were no significant associations between baseline subchondral sclerosis detected by MRI and cartilage loss in the same region of the knee. Conclusion Baseline subchondral sclerosis as detected by MRI did not increase the risk of cartilage loss over time.
    Osteoarthritis and Cartilage 04/2014; 22(4). DOI:10.1016/j.joca.2014.01.006 · 4.66 Impact Factor
  • Osteoarthritis and Cartilage 04/2014; 22:S270-S271. DOI:10.1016/j.joca.2014.02.508 · 4.66 Impact Factor
  • Annals of the Rheumatic Diseases 01/2014; 72(Suppl 3):A695-A695. DOI:10.1136/annrheumdis-2013-eular.2056 · 10.38 Impact Factor
  • Annals of the Rheumatic Diseases 01/2014; 72(Suppl 3):A348-A348. DOI:10.1136/annrheumdis-2013-eular.1071 · 10.38 Impact Factor
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    ABSTRACT: Objective To determine the risk of cardiovascular disease (CVD) among osteoarthritis (OA) patients using population-based administrative data from British Columbia, Canada. Methods The medical history of a random sample of 600,000 individuals from 1991-2009 was analyzed. A total of 12,745 OA cases and up to 3 non-OA individuals matched by age, sex, and year of diagnosis were followed for CVD events. Cox proportional hazards and Poisson regression models were used to estimate the relative risks (RRs) of CVD, myocardial infarction, ischemic heart disease (IHD), congestive heart failure (CHF), and stroke after adjusting for available sociodemographic and medical factors. ResultsOA was an independent predictor of CVD. The adjusted RRs were 1.15 (95% confidence interval [95% CI] 1.04-1.27), 1.26 (95% CI 1.13-1.42), and 1.17 (95% CI 1.07-1.26) among older men, younger women, and older women, respectively. Analyses were stratified by age and sex due to statistically significant interactions between OA and age and sex. RRs among older men, younger women, and older women were 1.33 (95% CI 1.11-1.62), 1.66 (95% CI 1.37-2.01), and 1.45 (95% CI 1.22-1.72) for IHD, respectively, and 1.25 (95% CI 1.02-1.54), 1.29 (95% CI 1.00-1.68), and 1.20 (95% CI 1.03-1.39) for CHF, respectively. Compared to non-OA individuals, OA cases who underwent total joint replacements had a 26% increased risk of CVD. Conclusion This prospective longitudinal study suggests that OA is associated with an increased risk of CVD. Older men and adult women with OA had a higher risk of CVD, particularly IHD and CHF. Further studies are needed to confirm these results and to elucidate the potential biologic mechanisms.
    12/2013; 65(12). DOI:10.1002/acr.22092
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    ABSTRACT: Abstract Background: Recent research has identified younger women as an "at-risk" population with rising prevalence of cardiac risk factors and excess mortality risk following acute myocardial infarction (AMI). However, population-based data on trends in AMI hospitalization and early mortality post AMI among younger adults is scarce. We, therefore, aimed to provide a 10-year, descriptive analysis of these trends in a Canadian setting. Methods and Results: We assessed trends and sex differences in AMI hospitalization and 30-day mortality rates using negative binomial and logistic regression, respectively. From 2000 to 2009, there were 70,628 AMI hospitalizations in adults aged ≥20 years, in British Columbia, Canada, with 17.1% of cohort being younger adults ≤55 years. Overall, age-standardized AMI rates (per 100,000 population) declined similarly in men (295.8 to 247.7) and women (152.1 to 128.8) [sex-year interaction p=0.81]. However, these trends differed according to age (age-sex-year interaction p=0.02) with increased rates observed only in younger women (+1.7% per year; p=0.04). The 30-day mortality rates declined similarly for women (19.4% to 13.9%) and men (13.0% to 9.3%) (sex-year interaction p=0.33). Yet, younger women continued to have excess mortality risk, compared with younger men, even in the most recent period [odds ratio: 2008-09=1.61 (95% onfidence interval: 1.25, 2.08)]. Conclusion: While the overall AMI hospitalization and 30-day mortality rates significantly declined in women and men, hospitalization rates in women ≤55 years increased and their excess risk of 30-day mortality persisted. These findings highlight the need to intensify strategies to reduce the incidence of AMI and improve outcomes after AMI in younger women.
    Journal of Women's Health 11/2013; 23(1). DOI:10.1089/jwh.2013.4507 · 1.90 Impact Factor
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    ABSTRACT: Adaptive tests are increasingly being used to assess health-related quality of life in patients with a variety of medical conditions, including osteoarthritis (OA) of the knee. This approach has recently been used to assess health state utility valuations (HSUV) for use in quality-adjusted life-year calculations. To accurately assess incremental value for money, these tools must be responsive. Therefore, we examined the responsiveness of the Health Utilities Index mark 3 (HUI3) and Paper Adaptive Test-5D (PAT-5DQOL) in a group of patients with knee OA. We used patient-level data from a randomized controlled trial evaluating a pharmacist-initiated multidisciplinary intervention in newly diagnosed patients with knee OA. The mean change for utility scores from baseline to 6 months was calculated, as well as effect size (ES) and standardized response mean (SRM) for the HUI3 and PAT-5DQOL, and generalized additive model plots, using the Western Ontario and McMaster Osteoarthritis index as a reference standard. When patients were assessed based on whether their condition had improved, remained unchanged, or worsened over time, the PAT-5DQOL showed greater responsiveness in patients whose condition had either improved or worsened. ES and SRM were generally small for both instruments. The PAT-5DQOL is more responsive to change over time than the HUI3 in patients with knee OA.
    The Journal of Rheumatology 11/2013; 40(12). DOI:10.3899/jrheum.130176 · 3.17 Impact Factor

Publication Stats

3k Citations
604.41 Total Impact Points


  • 2003–2015
    • University of British Columbia - Vancouver
      • • School of Population and Public Health
      • • Department of Medicine
      Vancouver, British Columbia, Canada
  • 2001–2014
    • Arthritis Research Centre of Canada
      Ричмонд, British Columbia, Canada
  • 2009
    • Simon Fraser University
      • Department of Statistics and Actuarial Sciences
      Burnaby, British Columbia, Canada
  • 2007
    • University of Pittsburgh
      Pittsburgh, Pennsylvania, United States
  • 2005
    • University of Ottawa
      Ottawa, Ontario, Canada
  • 2002–2003
    • Institute for Clinical Evaluative Sciences
      Toronto, Ontario, Canada
  • 1998
    • University of Toronto
      Toronto, Ontario, Canada
  • 1996
    • Sunnybrook Health Sciences Centre
      Toronto, Ontario, Canada
  • 1993
    • McGill University
      • Department of Medicine
      Montréal, Quebec, Canada