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Cadarette S.M.,University of Toronto | Cadarette S.M.,Institute for Clinical Evaluative science | Carney G.,University of British Columbia | Baek D.,University of Toronto | And 6 more authors.
Osteoporosis International

Summary We compared the patterns of osteoporosis medication prescribing between two provinces in Canada with different public drug coverage policies. Oral bisphosphonates were the primary drugs used, yet access to the secondgeneration oral bisphosphonates (alendronate, risedronate) was limited in one region. Implications of differential access to oral bisphosphonates warrants further study. Introduction Approved therapies for treating osteoporosis in Canada include bisphosphonates, calcitonin, denosumab, raloxifene, and teriparatide. However, significant variation in access to these medications through public drug coverage exists across Canada. We sought to compare patterns of osteoporosis medication prescribing between British Columbia (BC) and Ontario. Methods Using dispensing data from BC (PharmaNet) and Ontario (Ontario Drug Benefits), we identified all new users of osteoporosis medications aged 66 or more years from 1995/1996 to 2008/2009. We summarized the number of new users by fiscal year, sex, and index drug for each province. BC data were also stratified by whether drugs were dispensed within or outside public PharmaCare. Results We identified 578,254 (n=122,653 BC) eligible new users. Overall patterns were similar between provinces: (1) most patients received an oral bisphosphonate (93% in BC and 99% in Ontario); (2) etidronate prescribing declined after 2001/2002, reaching a low of 41% in BC and 10% in Ontario in 2008/2009; and (3) the proportion of males treated increased over time, from 7% in 1996/1997 to 25% in 2008/2009. However, we note major differences within versus outside the BC PharmaCare system. In particular, <2% of drugs dispensed within PharmaCare compared to 79% of drugs dispensed outside PharmaCare were for a secondgeneration bisphosphonate (alendronate or risedronate). Conclusions Oral bisphosphonates are the primary drugs used to treat osteoporosis in Canada. Prescribing practices changed over time as newer medications came to market, yet access to second-generation bisphosphonates through BC PharmaCare was limited. Implications of differential access to oral bisphosphonates warrants further study. © The Author(s) 2011. Source

Lam C.G.,University of Toronto | Manlhiot C.,University of Toronto | Pullenayegum E.M.,McMaster University | Pullenayegum E.M.,Center for Evaluation of Medicines | Feldman B.M.,University of Toronto
Annals of the Rheumatic Diseases

Intravenous immunoglobulin (IVIg) is an adjunctive therapy for juvenile dermatomyositis (JDM) patients with poor response to first-line therapy (corticosteroid resistant; SR) or who are corticosteroid dependent (SD). Patients requiring IVIg are generally expected to have poorer outcomes, leading to confounding by indication in observational studies. Few studies have evaluated IVIg efficacy in JDM. Objectives: Compared with similar matched controls, to determine if JDM IVIg recipients achieve quiescence sooner and have less disease activity. For SD patients, to determine if IVIg recipients exhibit less disease activity than IVIg-naive patients. Methods: A retrospective inception cohort of 78 JDM patients was studied. Kaplan-Meier survival determined time to quiescence. Marginal structural modelling was used to account for confounding by indication by incorporating inverse probability of treatment weights to handle patients' unequal likelihood of receiving IVIg. Results: While similar demographically, the 30 IVIg patients demonstrated weaker muscle strength and more had photosensitivity at baseline than the 48 controls. As expected, IVIg patients achieved quiescence later than controls in unadjusted analysis. However, although IVIg patients started with greater disease activity, after accounting for confounding as best possible, they maintained similar or lower disease activity than controls from 30 days to 4 years post-diagnosis. This improvement was most marked in SR patients. Among SD patients, IVIg recipients maintained lower disease activity than IVIg-naive patients. Conclusion: This study, involving the largest JDM cohort receiving IVIg to date, applied bias-reduction methods and demonstrated IVIg efficacy in controlling JDM disease activity, particularly for SR patients. Source

Levine M.A.H.,Center for Evaluation of Medicines | Levine M.A.H.,McMaster University | El-Nahas A.I.,Center for Evaluation of Medicines | Asa B.,Center for Evaluation of Medicines
Journal of Clinical Epidemiology

Objective: To determine the frequency of inappropriate use of arithmetic scales to present relative risk (RR) and odds ratio (OR) data in figures among a group of high-profile general medical journals. Study Design and Setting: Articles presenting RR or OR data in figures and published in one of five journals during 2002-2003 and 2007-2008 were evaluated to determine the type of scale used with the figures. Logarithmic and reciprocal (inverse) scales were identified as appropriate, whereas arithmetic scales were deemed inappropriate. If an article included one or more inappropriate figures, it was counted once as an incorrect publication. Results: Fifty-two percent (53 of 101) of the articles with a graphical presentation of RR or OR data had used an inappropriate scale in 2002-2003 and 25% (58 of 231) in the time period 2007-2008. Although all five journals showed some improvement over the 5-year interval, there continued to be a problem with inappropriate presentations occurring with one in four articles. Conclusion: Given the perpetuation of this problem, it may be time for the International Committee of Medical Journal Editors to address this issue by requiring that figures portraying ratio data use only logarithmic or reciprocal scales. © 2010 Elsevier Inc. All rights reserved. Source

Burden A.M.,University of Toronto | Paterson J.M.,Institute for Clinical Evaluative science | Paterson J.M.,University of Toronto | Paterson J.M.,McMaster University | And 7 more authors.
Osteoporosis International

We studied new users of oral bisphosphonates and found that less than half persisted with therapy for 2 years, and interruptions in use were common. During a median observation period of 4.7 years, 10% of patients filled only a single prescription, 37% switched therapies and median cumulative exposure was 2.2 years. Introduction: We sought to describe bisphosphonate prescribing, persistence and cumulative exposure among seniors in Ontario, Canada. Methods: We used Ontario Drug Benefit pharmacy claims to identify residents aged ≥ 66 years who initiated oral bisphosphonate therapy between April 1996 and March 2009. The first date of bisphosphonate dispensing was considered the index date. Persistence with therapy was defined as continuous treatment with no interruption exceeding 60 days. We examined persistence with therapy and the number of extended gaps (>60 days) between prescriptions over time periods ranging from 1 to 9 years. We also identified the proportion of patients filling only a single prescription and switching to a different bisphosphonate, and calculated the median days of exposure irrespective of gaps in therapy. Results: A total of 451,113 eligible new bisphosphonate users were identified: mean age = 75.6 years (SD = 6.9), 84% female, and median follow-up length = 4.7 years. Persistence with therapy declined from 63% at 1 year to 46% at 2 years and 12% at 9 years. Among those with at least 5 years of follow-up (n = 213,029), 61% had one or more extended gaps in bisphosphonate therapy. Overall, 10% of patients filled only a single prescription, 37% switched to a different bisphosphonate and the median exposure was 2.2 years. Conclusion: Less than half of patients persisted with bisphosphonate therapy for 2 years and interruptions in therapy were common, with most patients experiencing two or more >60-day gaps in therapy. Interventions are needed to improve persistence with bisphosphonate therapy and reduce the frequency of gaps in treatment. © 2011 The Author(s). Source

Xie F.,McMaster University | Oremus M.,McMaster University | Gaebel K.,McMaster University | Gaebel K.,Center for Evaluation of Medicines
Quality of Life Research

Purpose: Little research exists to indicate whether the general public can provide proxy health-related quality-oflife (HRQoL) estimates for persons with Alzheimer's disease (AD). We investigated (1) whether the general public can differentiate between mild, moderate, and severe AD and (2) whether the general public's proxy HRQoL estimates are correlated with current health status. Methods: We conducted computer-assisted personal interviews. The computer randomly assigned each participant to read a vignette describing mild, moderate, or severe AD. Participants answered the EQ-5D-5L and Quality-oflife-Alzheimer's Disease (QoL-AD), while imagining living in the health state described in their assigned vignette. Participants also answered the EQ-5D-5L based on their health state at the time of the interview. Results: We interviewed 100 participants. EQ-5D-5L utilities were 0.7413 (mild), 0.6159 (moderate), and 0.4456 (severe) (P<0.001). Mean QoL-AD scores were 32.5 (mild), 24.0 (moderate), and 21.8 (severe) (P <0.0001 for severe vs. mild, moderate vs. mild; P> 0.05 for severe vs. moderate). Participants' EQ-5D-5L utility scores were weakly correlated (r ≤ 0.28) across both administrations of the instrument. Conclusions: The general public can differentiate between the three stages of AD, and their HRQoL estimates for AD are weakly correlated with their current health status. © Springer Science+Business Media B.V. 2011. Source

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