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Dive into the research topics where Angela M. Cheung is active.

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Featured researches published by Angela M. Cheung.


Canadian Medical Association Journal | 2010

2010 clinical practice guidelines for the diagnosis and management of osteoporosis in Canada: summary

Alexandra Papaioannou; Suzanne Morin; Angela M. Cheung; Stephanie A. Atkinson; Jacques P. Brown; Sidney Feldman; David A. Hanley; Anthony B. Hodsman; Sophie A. Jamal; Stephanie M. Kaiser; Brent Kvern; Kerry Siminoski; William D. Leslie

See related commentary by Kanis, page [1829][1] Since the publication of the Osteoporosis Canada guidelines in 2002, there has been a paradigm shift in the prevention and treatment of osteoporosis and fractures. [1][2],[2][3] The focus now is on preventing fragility fractures and their negative


Journal of Bone and Mineral Research | 2011

Atypical Subtrochanteric and Diaphyseal Femoral Fractures: Report of a Task Force of the American Society for Bone and Mineral Research

Elizabeth Shane; David B. Burr; Peter R. Ebeling; Bo Abrahamsen; Robert A. Adler; Thomas D. Brown; Angela M. Cheung; Felicia Cosman; Jeffrey R. Curtis; Richard M. Dell; David W. Dempster; Thomas A. Einhorn; Harry K. Genant; Piet Geusens; Klaus Klaushofer; Kenneth J. Koval; Joseph M. Lane; Fergus McKiernan; Ross E. McKinney; Alvin Ng; Jeri W. Nieves; Regis J. O'Keefe; Socrates E. Papapoulos; Howe Tet Sen; Marjolein C. H. van der Meulen; Robert S. Weinstein; Michael P. Whyte

Bisphosphonates (BPs) and denosumab reduce the risk of spine and nonspine fractures. Atypical femur fractures (AFFs) located in the subtrochanteric region and diaphysis of the femur have been reported in patients taking BPs and in patients on denosumab, but they also occur in patients with no exposure to these drugs. In this report, we review studies on the epidemiology, pathogenesis, and medical management of AFFs, published since 2010. This newer evidence suggests that AFFs are stress or insufficiency fractures. The original case definition was revised to highlight radiographic features that distinguish AFFs from ordinary osteoporotic femoral diaphyseal fractures and to provide guidance on the importance of their transverse orientation. The requirement that fractures be noncomminuted was relaxed to include minimal comminution. The periosteal stress reaction at the fracture site was changed from a minor to a major feature. The association with specific diseases and drug exposures was removed from the minor features, because it was considered that these associations should be sought rather than be included in the case definition. Studies with radiographic review consistently report significant associations between AFFs and BP use, although the strength of associations and magnitude of effect vary. Although the relative risk of patients with AFFs taking BPs is high, the absolute risk of AFFs in patients on BPs is low, ranging from 3.2 to 50 cases per 100,000 person‐years. However, long‐term use may be associated with higher risk (∼100 per 100,000 person‐years). BPs localize in areas that are developing stress fractures; suppression of targeted intracortical remodeling at the site of an AFF could impair the processes by which stress fractures normally heal. When BPs are stopped, risk of an AFF may decline. Lower limb geometry and Asian ethnicity may contribute to the risk of AFFs. There is inconsistent evidence that teriparatide may advance healing of AFFs.


The New England Journal of Medicine | 2011

Functional Disability 5 Years after Acute Respiratory Distress Syndrome

Margaret S. Herridge; Catherine M. Tansey; Andrea Matte; George Tomlinson; Natalia Diaz-Granados; Andrew B. Cooper; Cameron B. Guest; C. David Mazer; Sangeeta Mehta; Thomas E. Stewart; Paul Kudlow; Deborah J. Cook; Arthur S. Slutsky; Angela M. Cheung

BACKGROUND There have been few detailed, in-person interviews and examinations to obtain follow-up data on 5-year outcomes among survivors of the acute respiratory distress syndrome (ARDS). METHODS We evaluated 109 survivors of ARDS at 3, 6, and 12 months and at 2, 3, 4, and 5 years after discharge from the intensive care unit. At each visit, patients were interviewed and examined; underwent pulmonary-function tests, the 6-minute walk test, resting and exercise oximetry, chest imaging, and a quality-of-life evaluation; and reported their use of health care services. RESULTS At 5 years, the median 6-minute walk distance was 436 m (76% of predicted distance) and the Physical Component Score on the Medical Outcomes Study 36-Item Short-Form Health Survey was 41 (mean norm score matched for age and sex, 50). With respect to this score, younger patients had a greater rate of recovery than older patients, but neither group returned to normal predicted levels of physical function at 5 years. Pulmonary function was normal to near-normal. A constellation of other physical and psychological problems developed or persisted in patients and family caregivers for up to 5 years. Patients with more coexisting illnesses incurred greater 5-year costs. CONCLUSIONS Exercise limitation, physical and psychological sequelae, decreased physical quality of life, and increased costs and use of health care services are important legacies of severe lung injury.


Stroke | 2005

Sex Differences in Stroke Care and Outcomes Results From the Registry of the Canadian Stroke Network

Moira K. Kapral; Jiming Fang; Michael D. Hill; Frank L. Silver; Janice A. Richards; Cheryl Jaigobin; Angela M. Cheung

Background— Stroke is an important cause of death and disability in women as well as men. However, little is known about sex differences in stroke care and outcomes. Methods— The Registry of the Canadian Stroke Network (RCSN) captured data on patients with stroke seen at acute care hospitals across Canada. We used data from phase 1 (July 2001 to February 2002) and phase 2 (June to December 2002) of the RCSN to compare stroke presentation, management, and 6-month outcomes in women and men using multivariable regression techniques to adjust for age and other factors. Results— The study sample included 3323 patients, with 1527 women. Stroke symptoms at presentation were similar in women and men, except that women were more likely to present with headaches and were less likely to have brain stem or cerebellar symptoms. There were no sex differences in the use of neuroimaging, thrombolysis, antithrombotic therapy, or consultations. Women were less likely than men to receive care on an acute stroke unit, but this difference was no longer significant after adjustment for age and other factors. Women were more likely than men to be discharged to long-term care and had greater disability at 6 months. Mortality and quality of life at 6 months were similar in women and men. Conclusions— Among patients participating in the RCSN, there were no major sex differences in stroke presentation or management. Compared with men, women were more often institutionalized and had a slightly worse functional status at 6 months after stroke.


Journal of Clinical Oncology | 2009

Impact of Androgen Deprivation Therapy on Cardiovascular Disease and Diabetes

Shabbir M.H. Alibhai; Minh Duong-Hua; Rinku Sutradhar; Neil Fleshner; Padraig Warde; Angela M. Cheung; Lawrence Paszat

PURPOSE Use of androgen deprivation therapy (ADT) may be associated with an increased risk of diabetes mellitus but the risk of both acute myocardial infarction (AMI) and cardiovascular mortality remain controversial because few outcomes and conflicting findings have been reported. We sought to clarify whether ADT is associated with these outcomes in a large, representative cohort. METHODS Using linked administrative databases in Ontario, Canada, men age 66 years or older with prostate cancer given continuous ADT for at least 6 months or who underwent bilateral orchiectomy (n = 19,079) were matched with men with prostate cancer who had never received ADT. Treated and untreated groups were matched 1:1 (ie, hard-matched) on age, prior cancer treatment, and year of diagnosis and propensity-matched on comorbidities, medications, cardiovascular risk factors, prior fractures, and socioeconomic variables. Primary outcomes were development of AMI, sudden cardiac death, and diabetes. Fragility fracture was also examined. Results The cohort was observed for a mean of 6.47 years. In time-to-event analyses, ADT use was associated with an increased risk of diabetes (hazard ratio [HR], 1.16; 95% CI, 1.11 to 1.21) and fragility fracture (HR, 1.65; 95% CI, 1.53 to 1.77) but not with AMI (HR, 0.91; 95% CI, 0.84 to 1.00) or sudden cardiac death (HR, 0.96; 95% CI, 0.83 to 1.10). Increasing duration of ADT was associated with an excess risk of fragility fractures and diabetes but not cardiac outcomes. CONCLUSION Continuous ADT use for at least 6 months in older men is associated with an increased risk of diabetes and fragility fracture but not AMI or sudden cardiac death.


PLOS Medicine | 2008

Vitamin K Supplementation in Postmenopausal Women with Osteopenia (ECKO Trial): A Randomized Controlled Trial

Angela M. Cheung; Lianne Tile; Yuna Lee; George Tomlinson; Gillian Hawker; Judy Scher; Hanxian Hu; Reinhold Vieth; Lilian U. Thompson; Sophie A. Jamal; Robert G. Josse

Background Vitamin K has been widely promoted as a supplement for decreasing bone loss in postmenopausal women, but the long-term benefits and potential harms are unknown. This study was conducted to determine whether daily high-dose vitamin K1 supplementation safely reduces bone loss, bone turnover, and fractures. Methods and Findings This single-center study was designed as a 2-y randomized, placebo-controlled, double-blind trial, extended for earlier participants for up to an additional 2 y because of interest in long-term safety and fractures. A total of 440 postmenopausal women with osteopenia were randomized to either 5 mg of vitamin K1 or placebo daily. Primary outcomes were changes in BMD at the lumbar spine and total hip at 2 y. Secondary outcomes included changes in BMD at other sites and other time points, bone turnover markers, height, fractures, adverse effects, and health-related quality of life. This study has a power of 90% to detect 3% differences in BMD between the two groups. The women in this study were vitamin D replete, with a mean serum 25-hydroxyvitamin D level of 77 nmol/l at baseline. Over 2 y, BMD decreased by −1.28% and −1.22% (p = 0.84) (difference of −0.06%; 95% confidence interval [CI] −0.67% to 0.54%) at the lumbar spine and −0.69% and −0.88% (p = 0.51) (difference of 0.19%; 95% CI −0.37% to 0.75%) at the total hip in the vitamin K and placebo groups, respectively. There were no significant differences in changes in BMD at any site between the two groups over the 2- to 4-y period. Daily vitamin K1 supplementation increased serum vitamin K1 levels by 10-fold, and decreased the percentage of undercarboxylated osteocalcin and total osteocalcin levels (bone formation marker). However, C-telopeptide levels (bone resorption marker) were not significantly different between the two groups. Fewer women in the vitamin K group had clinical fractures (nine versus 20, p = 0.04) and fewer had cancers (three versus 12, p = 0.02). Vitamin K supplements were well-tolerated over the 4-y period. There were no significant differences in adverse effects or health-related quality of life between the two groups. The study was not powered to examine fractures or cancers, and their numbers were small. Conclusions Daily 5 mg of vitamin K1 supplementation for 2 to 4 y does not protect against age-related decline in BMD, but may protect against fractures and cancers in postmenopausal women with osteopenia. More studies are needed to further examine the effect of vitamin K on fractures and cancers. Trial registration: ClinicalTrials.gov (#NCT00150969) and Current Controlled Trials (#ISRCTN61708241)


Journal of General Internal Medicine | 2004

The effect of English language proficiency on length of stay and in-hospital mortality

Ava John-Baptiste; Gary Naglie; George Tomlinson; Shabbir M.H. Alibhai; Edward Etchells; Angela M. Cheung; Moira K. Kapral; Wayne L. Gold; Howard Abrams; Maria Bacchus; Murray Krahn

AbstractBACKGROUND: In ambulatory care settings, patients with limited English proficiency receive lower quality of care. Limited information is available describing outcomes for inpatients. OBJECTIVE: To investigate the effect of English proficiency on length of stay (LOS) and in-hospital mortality. DESIGN: Retrospective analysis of administrative data at 3 tertiary care teaching hospitals (University Health Network) in Toronto, Canada. PARTICIPANTS: Consecutive inpatient admissions from April 1993 to December 1999 were analyzed for LOS differences first by looking at 23 medical and surgical conditions (59,547 records) and then by a meta-analysis of 220 case mix groups (189,119 records). We performed a similar analysis for in-hospital mortality. MEASUREMENTS: LOS and odds of in-hospital death for limited English-proficient (LEP) patients relative to English-proficient (EP) patients. RESULTS: LEP patients stayed in hospital longer for 7 of 23 conditions (unstable coronary syndromes and chest pain, coronary artery bypass grafting, stroke, craniotomy procedures, diabetes mellitus, major intestinal and rectal procedures, and elective hip replacement), with LOS differences ranging from approximately 0.7 to 4.3 days. A meta-analysis using all admission data demonstrated that LEP patients stayed 6% (approximately 0.5 days) longer overall than EP patients (95% confidence interval, 0.04 to 0.07). LEP patients were not at increased risk of in-hospital death (relative odds, 1.0; 95% confidence interval, 0.9 to 1.1). CONCLUSIONS: Patients with limited English proficiency have longer hospital stays for some medical and surgical conditions. Limited English proficiency does not affect in-hospital mortality. The effect of communication barriers on outcomes of care in the inpatient setting requires further exploration, particularly for selected conditions in which length of stay is significantly prolonged.


Clinical Cancer Research | 2004

Effects of the steroidal aromatase inhibitor Exemestane and the nonsteroidal aromatase inhibitor letrozole on bone and lipid metabolism in ovariectomized rats

Paul E. Goss; Shangle Qi; Angela M. Cheung; Haiqing Hu; Maria Mendes; Kenneth P.H. Pritzker

Purpose: Exemestane (EXE) and letrozole (LET) are third-generation aromatase inhibitors currently prescribed for postmenopausal hormone-dependent breast cancer. The impact on end organs of estrogen depletion in menopausal women is of significant clinical importance. We studied the effects of EXE, its principal metabolite, 17-hydroexemestane (17-H-EXE), and LET on bone and lipid metabolism in ovariectomized (OVX) rats. Experimental Design: OVX rats were treated by weekly intramuscular injection for 16 weeks with 20, 50, and 100 mg/kg EXE, 20 mg/kg 17-H-EXE, and daily oral gavage of 1 mg/kg LET. At the end of the treatment period, bone mineral density (BMD), the bone resorption marker serum pyridinoline, the bone formation marker serum osteocalcin, bone mechanical properties, histomorphometry, and serum lipid concentrations were determined. Results: Lumbar vertebral and femoral BMD, bending strength of the femur, compressive strength of the fifth lumbar vertebra, and trabecular bone volume were significantly higher in OVX animals given EXE and 17-H-EXE than in OVX controls. EXE and 17-H-EXE significantly reduced an ovariectomy-induced increase in serum pyridinoline and serum osteocalcin. EXE and 17-H-EXE given to OVX rats caused significant reductions of serum cholesterol and low-density lipoprotein cholesterol. In contrast, OVX rats treated with LET had BMD, bone biomarkers, mechanical failure properties, and lipid levels similar to those of OVX controls. Conclusions: EXE and 17-H-EXE significantly prevent bone loss, enhance bone mechanical strength, and lower serum cholesterol and low-density lipoprotein levels in OVX rats. These protective effects on end-organ function are not seen with the nonsteroidal inhibitor LET.


Lancet Oncology | 2012

Bone density and structure in healthy postmenopausal women treated with exemestane for the primary prevention of breast cancer: a nested substudy of the MAP.3 randomised controlled trial

Angela M. Cheung; Lianne Tile; Savannah Cardew; Sandhya Pruthi; John Robbins; George Tomlinson; Moira K. Kapral; Sundeep Khosla; Sharmila Majumdar; Marta Erlandson; Judy Scher; Hanxian Hu; Alice Demaras; Lavina Lickley; Louise Bordeleau; Christine Elser; James N. Ingle; Harriet Richardson; Paul E. Goss

BACKGROUND Exemestane can prevent breast cancer in postmenopausal women. Because of potential widespread use, we examined the safety of exemestane on bone health. METHODS In this nested safety substudy of the MAP.3 trial (a randomised, placebo-controlled, double-blind trial of exemestane 25 mg a day for the primary prevention of breast cancer), we included postmenopausal women from five centres who were eligible to participate in MAP.3, not osteoporotic, not receiving drugs for bone-related disorders, with baseline lumbar spine, total hip, and femoral neck T-scores above -2·0. The primary endpoint was percent change from baseline to 2 years in total volumetric bone mineral density (BMD) at the distal radius by high-resolution peripheral quantitative CT. The primary analysis was per protocol using a non-inferiority margin. This analysis was done earlier than originally planned because of the impending announcement of MAP.3 results and subsequent unmasking of patients to treatment assignment. This study is registered with ClinicalTrials.gov, number NCT01144468, and has been extended to 5 years of unmasked follow-up. FINDINGS 351 women (176 given exemestane, 175 given placebo; median age 61·3 years [IQR 59·2-64·9]) met our inclusion criteria and completed baseline assessment. At the time of clinical cutoff, 242 women had completed 2-year follow-up (124 given exemestane, 118 given placebo). From baseline to 2 years, the mean percent change in total volumetric BMD at the distal radius was -6·1% (95% CI -7·0 to -5·2) in the exemestane group and -1·8% (-2·4 to -1·2) in the placebo group (difference -4·3%, 95% CI -5·3 to -3·2; p<0·0001). The lower limit of the 95% CI was lower than our non-inferiority margin of negative 4% (one-sided test for non-inferiority p=0·70), meaning the hypothesis that exemestane was inferior could not be rejected. At the distal tibia, the mean percent change in total volumetric BMD from baseline to 2 years was -5·0% (95% CI -5·5 to -4·4) in the exemestane group and -1·3% (-1·7 to -1·0) in the placebo group (difference -3·7%, 95% CI -4·3 to -3·0; p<0·0001). The mean percent change in cortical thickness was -7·9% (SD 7·3) in the exemestane group and -1·1% (5·7) in the placebo group at the distal radius (difference -6·8%, 95% CI -8·5 to -5·0; p<0·0001) and -7·6% (SD 5·9) in the exemestane group and -0·7% (4·9) in the placebo group at the distal tibia (difference -6·9%, -8·4 to -5·5; p<0·0001). Decline in areal BMD, as measured by dual-energy x-ray absorptiometry, in the exemestane group compared with the placebo group occurred at the lumbar spine (-2·4% [95% CI -3·1 to -1·7] exemestane vs -0·5% [-1·1 to 0·2] placebo; difference -1·9%, 95% CI -2·9 to -1·0; p<0·0001), total hip (-1·8% [-2·3 to -1·2] exemestane vs -0·6% [-1·1 to -0·1] placebo; difference -1·2%, -1·9 to -0·4; p=0·004), and femoral neck (-2·4% [-3·2 to -1·7] exemestane vs -0·8% [-1·5 to 0·1] placebo; difference -1·6%, -2·7 to -0·6; p=0·002). INTERPRETATION 2 years of treatment with exemestane worsens age-related bone loss in postmenopausal women despite calcium and vitamin D supplementation. Women considering exemestane for the primary prevention of breast cancer should weigh their individual risks and benefits. For women taking exemestane, regular bone monitoring plus adequate calcium and vitamin D supplementation are important. To assess the effect of our findings on fracture risk, long-term follow-up is needed. FUNDING Canadian Breast Cancer Research Alliance (Canadian Institutes of Health Research/Canadian Cancer Society).


The Journal of Urology | 2010

Fracture Types and Risk Factors in Men With Prostate Cancer on Androgen Deprivation Therapy: A Matched Cohort Study of 19,079 Men

Shabbir M.H. Alibhai; Minh Duong-Hua; Angela M. Cheung; Rinku Sutradhar; Padraig Warde; Neil Fleshner; Lawrence Paszat

PURPOSE Accumulating evidence shows that androgen deprivation therapy is associated with osteoporosis and fragility fractures of the spine, hip and wrist. One study suggested that androgen deprivation therapy may also be associated with nonfragility fractures in older men. Whether other clinical risk factors independently increase the risk of fractures is not certain. MATERIALS AND METHODS Using linked administrative databases in Ontario, Canada, we matched 19,079 men 66 years old or older with prostate cancer with at least 6 months of continuous androgen deprivation therapy or bilateral orchiectomy with men with prostate cancer who had never received androgen deprivation. Matching variables were age, prior cancer treatment, diagnosis year, comorbidity, medication, prior fractures and socioeconomic variables. Primary outcomes were a typical fragility fracture of the spine, hip or wrist and any fracture. Independent predictors of fracture outcomes were assessed with Cox proportional hazards models. RESULTS At a mean 6.47-year followup androgen deprivation therapy was associated with an increased risk of fragility fracture (HR 1.65, 95% CI 1.53-1.78) and any fracture (HR 1.46, 95% CI 1.39-1.54). Independent predictors of fragility and any fracture were increasing age, prior bone thinning medications, chronic kidney disease, prior dementia, prior fragility fracture and prior osteoporosis diagnosis or treatment (p <0.05). CONCLUSIONS Continuous androgen deprivation therapy for at least 6 months is associated with an increased risk of fracture. Increasing age, prior osteoporotic fracture and dementia are important clinical factors that may warrant greater consideration of anti-osteoporotic therapy in these men.

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Padraig Warde

Princess Margaret Cancer Centre

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