Andrea S Gershon

Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada

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Publications (45)240.59 Total impact

  • JAMA Internal Medicine 04/2014; 174(4):648. · 10.58 Impact Factor
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    ABSTRACT: Obstructive sleep apnea (OSA) has been reported to be a risk factor for cardiovascular (CV) disease. Although the apnea-hypopnea index (AHI) is the most commonly used measure of OSA, other less well studied OSA-related variables may be more pathophysiologically relevant and offer better prediction. The objective of this study was to evaluate the relationship between OSA-related variables and risk of CV events. A historical cohort study was conducted using clinical database and health administrative data. Adults referred for suspected OSA who underwent diagnostic polysomnography at the sleep laboratory at St Michael's Hospital (Toronto, Canada) between 1994 and 2010 were followed through provincial health administrative data (Ontario, Canada) until May 2011 to examine the occurrence of a composite outcome (myocardial infarction, stroke, congestive heart failure, revascularization procedures, or death from any cause). Cox regression models were used to investigate the association between baseline OSA-related variables and composite outcome controlling for traditional risk factors. The results were expressed as hazard ratios (HRs) and 95% CIs; for continuous variables, HRs compare the 75th and 25th percentiles. Over a median follow-up of 68 months, 1,172 (11.5%) of 10,149 participants experienced our composite outcome. In a fully adjusted model, other than AHI OSA-related variables were significant independent predictors: time spent with oxygen saturation <90% (9 minutes versus 0; HR = 1.50, 95% CI 1.25-1.79), sleep time (4.9 versus 6.4 hours; HR = 1.20, 95% CI 1.12-1.27), awakenings (35 versus 18; HR = 1.06, 95% CI 1.02-1.10), periodic leg movements (13 versus 0/hour; HR = 1.05, 95% CI 1.03-1.07), heart rate (70 versus 56 beats per minute [bpm]; HR = 1.28, 95% CI 1.19-1.37), and daytime sleepiness (HR = 1.13, 95% CI 1.01-1.28).The main study limitation was lack of information about continuous positive airway pressure (CPAP) adherence. OSA-related factors other than AHI were shown as important predictors of composite CV outcome and should be considered in future studies and clinical practice. Please see later in the article for the Editors' Summary.
    PLoS Medicine 02/2014; 11(2):e1001599. · 15.25 Impact Factor
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    ABSTRACT: BACKGROUND:To comprehensively examine the cardiovascular health of Canadians, we developed the Cardiovascular Health in Ambulatory Care Research Team (CANHEART) health index. We analyzed trends in health behaviours and factors to monitor the cardiovascular health of the Canadian population. METHODS:We used data from the Canadian Community Health Survey (2003-2011 [excluding 2005]; response rates 70%-81%) to examine trends in the prevalence of 6 cardio vascular health factors and behaviours (smoking, physical activity, fruit and vegetable consumption, overweight/obesity, diabetes and hypertension) among Canadian adults aged 20 or older. We defined ideal criteria for each of the 6 health metrics. The number of ideal metrics was summed to create the CANHEART health index; values range from 0 (worst) to 6 (best or ideal). A separate CANHEART index was developed for youth age 12-19 years; this index included 4 health factors and behaviours (smoking, physical activity, fruit and vegetable consumption and overweight/obesity). We determined the prevalence of ideal cardiovascular health and the mean CANHEART health index score, stratified by age, sex and province. RESULTS:During the study period, physical activity and fruit and vegetable consumption increased and smoking decreased among Canadian adults. The prevalence of overweight/ obesity, hypertension and diabetes increased. In 2009-2010, 9.4% of Canadian adults were in ideal cardiovascular health, 53.3% were in intermediate health (4-5 healthy factors or behaviours), and 37.3% were in poor cardiovascular health (0-3 healthy factors or behaviours). Twice as many women as men were in ideal cardiovascular health (12.8% vs. 6.1%). Among youth, the prevalence of smoking decreased and the prevalence of overweight/obesity increased. In 2009-2010, 16.6% of Canadian youth were in ideal cardiovascular health, 33.7% were in intermediate health (3 healthy factors or behaviours), and 49.7% were in poor cardiovascular health (0-2 healthy factors or behaviours). INTERPRETATION:Fewer than 1 in 10 Canadian adults and 1 in 5 Canadian youth were in ideal cardiovascular health from 2003 to 2011. Intensive health promotion activities are needed to meet the Heart and Stroke Foundation of Canada's goal of improving the cardiovascular health of Canadians by 10% by 2020 as measured by the CANHEART health index.
    Canadian Medical Association Journal 12/2013; · 6.47 Impact Factor
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    ABSTRACT: Objectives To better understand how centenarians use the healthcare system as an important step toward improving their service delivery. DesignPopulation-based retrospective cohort study using linked health administrative data. SettingOntario—Canada's largest province. ParticipantsAll individuals living in Ontario aged 65 and older on April 1 of each year between 1995 and 2010 were identified and divided into three age groups (65–84, 85–99, ≥100). A detailed description was obtained on 1,842 centenarians who were alive on April 1, 2010. MeasurementsSociodemographic characteristics and use of health services. ResultsThe number of centenarians increased from 1,069 in 1995 to 1,842 in 2010 (72.3%); 6.7% were aged 105 and older. Over the same period, the number of individuals aged 85 to 99 grew from 119,955 to 227,703 (89.8%). Women represented 85.3% of all centenarians and 89.4% of those aged 105 and older. Almost half of centenarians lived in the community (20.0% independently, 25.3% with publicly funded home care). Preventive drug therapies (bisphosphonates and statins) were frequently dispensed. In the preceding year, 18.2% were hospitalized and 26.6% were seen in an emergency department. More than 95% saw a primary care provider, and 5.3% saw a geriatrician. Conclusion The number of centenarians in Ontario increased by more than 70% over the last 15 years, with even greater growth among older people who could soon become centenarians. Almost half of centenarians live in the community, most are women, and almost all receive care from a primary care physician.
    Journal of the American Geriatrics Society 12/2013; · 3.98 Impact Factor
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    ABSTRACT: Introduction: We previously found a relationship between obstructive sleep apnea (OSA)-related variables and a composite outcome of all-cause death, congestive heart failure (CHF), acute myocardial infarction (AMI), stroke, coronary artery bypass grafting or percutaneous coronary intervention. There is limited evidence on associations between OSA and separate cardiovascular (CV) events or the impact of competing risks on non-fatal outcomes. We investigated relationships with the main components of our composite, with and without adjusting for competing risk of death. Materials and methods: All adults referred with suspected OSA who underwent a first diagnostic sleep study at St Michael’s Hospital (Toronto, Canada) between 1994 and 2010 were included. Patient data was linked to health administrative data. Our statistical model for a composite outcome controls for traditional CV risk factors and includes total sleep time (TST) with O2 saturation <90%, TST, number of awakenings, periodic leg movements, heart rate in TST and daytime sleepiness (DS). The model was refitted to components of the composite. Subjects were followed from their first diagnostic sleep study to March 2011, the occurrence of the event of interest (CHF, AMI, stroke), or death, whichever occurred first. The Fine and Gray competing-risk model and Cox model were used. Results: A total of 10,149 participants (62% males, mean age 50 years) were followed over a median of 68 months There were 762 deaths, potentially competing events, and the following numbers of first CV events: 414 hospitalized CHFs (542 died without CHF); 145 hospitalized AMIs (712 died without an AMI); 100 hospitalized strokes (732 died without stroke). The Kaplan–Meier method overestimated the cumulative incidence of CV events by 3% at 100 months. In the Cox model all predictors except DS were significantly associated with all-cause death and CHF, but only TST and awakenings with stroke. In a competing risk model, the effect of awakenings became non-significant for both CHF and stroke, remaining significant only for all-cause mortality. OSA–related variables were not associated with incident AMI in either model. Conclusion: All-cause mortality, stroke and CHF are significantly associated with some OSA-related variables. The findings for OSA variables were mostly unchanged in competing risk models. Nonetheless, we recommend competing risks analyses as a complementary approach to traditional Cox models, especially in frail populations.
    5th World Congress on Sleep Medicine, 28 September to 2 October 2013, Valencia, Spain; 09/2013
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    ABSTRACT: ABSTRACT BACKGROUND The diagnosis of chronic obstructive pulmonary disease (COPD) is made by objectively demonstrating non-reversible airflow obstruction of the lungs. Despite this, rates of pulmonary function testing for diagnosis remain low. It is still not known why testing is under-used. METHODS We conducted a population study using the health administrative data of all individuals age 35 years and older newly diagnosed with COPD in Ontario, Canada between 2000 and 2010. Receipt of pulmonary function testing during the peridiagnostic period (between one year before and one year after a diagnosis of COPD) was determined and related to patient demographic and clinical characteristics as well as primary care physician and health care system factors. RESULTS Only 35.9% of the 491,754 Ontarians newly diagnosed with COPD during the study period received pulmonary function testing. Individuals diagnosed before age 50 or after age 80, those living in long term care and those with stroke and/or dementia were less likely to receive testing. Patients who had a medical specialist involved in their care and/or had other co-existing pulmonary disease were more likely to receive testing. Finally, older primary care physicians were less likely to order testing for their patients. CONCLUSION Only about one third of individuals with COPD in Ontario, Canada received pulmonary function testing to confirm their diagnosis; age, comorbidity and physician factors appear to influence its use. Targeted strategies that address these factors could increase the rate of appropriate testing of people with suspected COPD and improve quality of COPD care.
    Chest 09/2013; · 5.85 Impact Factor
  • Conference Proceeding: SLEEP 2013
    The 27th Annual Meeting of the Associated Professional Sleep Societies, LLC (APSS), SLEEP 2013., Baltimore, Maryland; 06/2013
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    ABSTRACT: IMPORTANCE Chronic obstructive pulmonary disease (COPD) is a common and deadly disease. Long-acting inhaled β-agonists and anticholinergics, first-line medications for COPD, have been associated with increased risk of cardiovascular outcomes. When choosing between the medications, patients and physicians would benefit from knowing which has the least risk. OBJECTIVE To assess the association of these classes of medications with the risk of hospitalizations and emergency department visits for cardiovascular events. DESIGN We conducted a nested case-control analysis of a retrospective cohort study. We compared the risk of events between patients newly prescribed inhaled long-acting β-agonists and anticholinergics, after matching and adjusting for prognostic factors. SETTING Health care databases from Ontario, the largest province of Canada, with a multicultural population of approximately 13 million. PARTICIPANTS All individuals 66 years or older meeting a validated case definition of COPD, based on health administrative data, and treated for COPD from September 1, 2003, through March 31, 2009. EXPOSURE New use of an inhaled long-acting β-agonist or long-acting anticholinergic. MAIN OUTCOME AND MEASURES An emergency department visit or a hospitalization for a cardiovascular event. RESULTS Of 191 005 eligible patients, 53 532 (28.0%) had a hospitalization or an emergency department visit for a cardiovascular event. Newly prescribed long-acting inhaled β-agonists and anticholinergics were associated with a higher risk of an event compared with nonuse of those medications (respective adjusted odds ratios, 1.31 [95% CI, 1.12-1.52; P < .001] and 1.14 [1.01-1.28; P = .03]). We found no significant difference in events between the 2 medications (adjusted odds ratio of long-acting inhaled β-agonists compared with anticholinergics, 1.15 [95% CI, 0.95-1.38; P = .16]). CONCLUSIONS AND RELEVANCE Among older individuals with COPD, new use of long-acting β-agonists and anticholinergics is associated with similar increased risks of cardiovascular events. Close monitoring of COPD patients requiring long-acting bronchodilators is needed regardless of drug class.
    JAMA Internal Medicine 05/2013; · 10.58 Impact Factor
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    ABSTRACT: BACKGROUND: Reports on the association between obstructive sleep apnea (OSA) and risk of death, cardiovascular (CV) events, diabetes and depression have been inconsistent. METHODS: We conducted a systematic review of the prognostic value of clinical and polysomnographic (PSG) characteristics of OSA for adverse long-term outcomes of untreated OSA in adult patients. A comprehensive search strategy for prognosis studies, OSA, CV events, mortality, depression and diabetes was developed in collaboration with a medical information specialist. All English language studies, from Jan 1999 to Dec 2011, with longitudinal design in adults with OSA diagnosed by PSG recording, found through Medline, Embase and bibliographies of identified articles, were considered eligible. Quality was assessed using published guidelines. RESULTS: Among 26 articles, ten evaluated the association of OSA with mortality, 9 with a composite CV outcome, 4 with stroke, 2 with diabetes and 1 with depression. Significant relationships between the apnea-hypopnea index (AHI) and outcomes of interest were reported in 18 studies: seven for all-cause mortality, six for composite CV events, three for stroke, one for diabetes and one for depression. The effect of AHI was attenuated by female gender, older age, absence of daytime sleepiness and higher body mass index. Due to clinical heterogeneity between studies, meta-analyses were not performed. CONCLUSION: Evidence exists in men for a relationship between OSA and all-cause mortality and a composite CV outcome. Associations between OSA and other outcomes remain uncertain. Among OSA-specific markers, only AHI was a consistent predictor. Other consistent predictors were traditional CV risk factors. Research is required to identify effect modifiers and the predictive ability of various AHI threshold values and hypopnea definitions. An enhanced set of OSA-specific predictors will allow better risk stratification to guide OSA treatment.
    Sleep Medicine Reviews 04/2013; · 8.68 Impact Factor
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    ABSTRACT: BACKGROUND: Recent evidence regarding temporal trends of asthma burden has not been consistent, with some countries reporting decreases in prevalence of asthma. In Ontario, the province in Canada with the highest population, the prevalence of asthma rose at a rate of 0.5% per year between 1996 and 2005. These estimates were based on population-based health services use data spanning more than a decade and provide a powerful source to forecast the trends of asthma burden. The objective of this study was to use observed population trends data of asthma incidence and prevalence to forecast future disease burden. METHODS: The Ontario Asthma Surveillance Information System (OASIS) used health administrative databases to identify and track all individuals in the province with asthma. Individuals with asthma identified between April 1, 1996 and March 31, 2010 were included. Exponential smoothing models were applied to annual data to project incidence to the year 2022, prevalence was estimated by applying the cumulative projected incidence to the projected population. RESULTS: While asthma incidence is falling, the absolute number of prevalent cases will continue to rise. We projected that almost 1 in 8 individuals in Ontario will have asthma by the year 2022, suggesting that asthma will continue to be a major burden on individuals and the health care system. CONCLUSIONS: These projections will help inform health care planners and decision-makers regarding resource allocation to optimize asthma outcomes.
    BMC Public Health 03/2013; 13(1):254. · 2.08 Impact Factor
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    ABSTRACT: BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) may receive benzodiazepines for a variety of reasons, including as treatment for insomnia, as treatment for depression and anxiety, and to help relieve refractory dyspnoea. However, benzodiazepines have been linked to adverse physiological respiratory outcomes in individuals with COPD. The potential adverse respiratory effects of benzodiazepines in COPD may also be heightened in older adults given their altered pharmacokinetics that increase benzodiazepine half-life. There is minimal information on the scope and nature of benzodiazepine use in the older adult COPD population. OBJECTIVE: The purpose of this study was to describe patterns of benzodiazepine use among older adults with COPD. METHODS: A validated algorithm was applied to Ontario healthcare administrative data to identify older adults with COPD. Incident oral benzodiazepine receipt between 1 April 2004 and 31 March 2009, defined as no benzodiazepines dispensed in the year prior to incident prescription, was examined. Regression techniques were used to identify patient characteristics associated with new benzodiazepine use. Descriptive statistics were performed to describe benzodiazepine use among new users. The analysis was stratified by COPD severity defined by COPD exacerbation frequency (less severe COPD: 0 exacerbations in the year prior; more severe COPD: 1 or more exacerbations in the year prior). RESULTS: Among 111,445 older adults with COPD, 35,311 (31.7 %) received a new benzodiazepine. New benzodiazepine receipt was higher among individuals with more severe COPD (adjusted odds ratio 1.43, 95 % CI 1.38-1.48). Among new benzodiazepine users, there was a relatively high frequency of receipt of long-acting agents (14.6 %), dispensations for greater than 30 days (32.6 %), second dispensations (22.0 % or 30.6 % for occurrence within 120 % or 200 % days of the index prescription, respectively), early refills (11.6 %), and benzodiazepine receipt during COPD exacerbations (9.0 %). Among individuals with more severe COPD, 35.4 % of incident use occurred during a COPD exacerbation. CONCLUSIONS: Almost one-third of older individuals with COPD received a new benzodiazepine, and rates were higher among those with more severe COPD. Important safety and quality of care issues are potentially raised by the degree and pattern of benzodiazepine use in this older and respiratory-vulnerable population.
    Drugs & Aging 02/2013; · 2.65 Impact Factor
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    ABSTRACT: Rationale Chronic obstructive pulmonary disease (COPD), a common manageable condition, is a leading cause of death. A better understanding of its impact on health care systems would inform strategies to reduce its burden. Objective To quantify health services use in a large, North American COPD population. Methods We conducted a cohort study using health administrative data from Ontario, a province with a population of 13 million and universal health care insurance. All individuals with physician diagnosed COPD in 2008 were identified and followed for 3 years. Proportions of all hospital visits, emergency department visits, ambulatory care visits, long term care residence places, and homecare by people made or used with COPD were determined and rates of each compared between people with and without COPD. Measurements and Main Results A total of 853,438 individuals with COPD (11.8% of the population age 35 and older) were responsible for 24% of hospitalizations, 24% of emergency department visits, 21% of ambulatory care visits and filled 35% of long term care places and used 30% of homecare services. After adjusting for several factors, people with COPD had rates of hospital, emergency department and ambulatory care visits that were, respectively, 63%, 85%, and 48% higher rates than the rest of the population. Their rates of long term care and homecare use were 56% and 59% higher. Conclusions Individuals with COPD use large and disproportionate amounts of health services. Strategies that target this group are needed to improve their health and minimize their need for health services.
    American Journal of Respiratory and Critical Care Medicine 01/2013; · 11.04 Impact Factor
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    ABSTRACT: [This corrects the article on p. e34967 in vol. 7.].
    PLoS ONE 01/2013; 8(1). · 3.73 Impact Factor
  • Saba Khan, David A Henry, Andrea S Gershon
    Canadian respiratory journal: journal of the Canadian Thoracic Society 11/2012; 19(6):353-4. · 1.29 Impact Factor
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    ABSTRACT: PURPOSE: Administrative healthcare databases are used for health services research, comparative effectiveness studies, and measuring quality of care. Adjustment for comorbid illnesses is essential to such studies. Validation of methods to account for comorbid illnesses in administrative data for patients with chronic obstructive pulmonary disease (COPD) has been limited. Our objective was to compare the ability of the Charlson index, the Elixhauser method, and the Johns Hopkins' Aggregated Diagnosis Groups (ADGs) to predict outcomes in patients with COPD. METHODS: Retrospective cohorts constructed using population-based administrative data of patients with incident (n = 216,735) and prevalent (n = 638,926) COPD in Ontario, Canada, were divided into derivation and validation datasets. The primary outcome was all-cause death within 1 year. Secondary outcomes included all-cause hospitalization, COPD-specific hospitalization, non-COPD hospitalization, and COPD exacerbations. RESULTS: In both the incident and prevalent COPD cohorts, the three methods had comparable discrimination for predicting mortality (c-statistics in the validation sample of incident patients of 0.819 for the Charlson method versus 0.822 for the Elixhauser method versus 0.830 for the ADG method). All three methods had lower predictive accuracy for predicting nonfatal outcomes. CONCLUSIONS: In a disease-specific cohort of COPD patients, all three methods allowed for accurate prediction of mortality, with the Johns Hopkins ADGs having marginally higher discrimination.
    Annals of epidemiology 10/2012; · 2.95 Impact Factor
  • Article: Response.
    Chest 10/2012; 142(4):1072-3. · 5.85 Impact Factor
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    ABSTRACT: Along with age and sex, socioeconomic status is one of the most powerful determinants of health. We conducted a systematic review to examine the consistency and magnitude of the association between socioeconomic status and COPD health outcomes to determine the potential impact of SES disparity on the COPD population. Electronic databases to October 2011 were searched for studies of adults who had or were at risk for COPD that quantified an association between a measure of socioeconomic status and at least one COPD health outcome. Two authors independently reviewed studies, assessed study quality, and for eligible studies, extracted data. Regardless of the population, socioeconomic status measure or COPD outcome examined, with few exceptions, consistent significant inverse associations between socioeconomic status and COPD outcomes were found. Most studies found that individuals of the lowest socioeconomic strata were at least twice as likely to have poor outcomes as those of the highest (range from no difference to 10-fold difference). Social and economic disadvantage appears to have a significant consistent impact on COPD mortality and morbidity. These findings point to the need for public health strategies and research to address socioeconomic status disparity in individuals with COPD.
    COPD Journal of Chronic Obstructive Pulmonary Disease 04/2012; 9(3):216-26. · 2.31 Impact Factor
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    ABSTRACT: Asthma is a major cause of disability, health resource utilization and poor quality of life world-wide. We set out to generate estimates of the global burden of asthma in adults, which may inform the development of strategies to address this common disease. The World Health Survey (WHS) was developed and implemented by the World Health Organization in 2002-2003. A total of 178,215 individuals from 70 countries aged 18 to 45 years responded to questions related to asthma and related symptoms. The prevalence of asthma was based on responses to questions relating to self-reported doctor diagnosed asthma, clinical/treated asthma, and wheezing in the last 12 months. The global prevalence rates of doctor diagnosed asthma, clinical/treated asthma and wheezing in adults were 4.3%, 4.5%, and 8.6% respectively, and varied by as much as 21-fold amongst the 70 countries. Australia reported the highest rate of doctor diagnosed, clinical/treated asthma, and wheezing (21.0%, 21.5%, and 27.4%). Amongst those with clinical/treated asthma, almost 24% were current smokers, half reported wheezing, and 20% had never been treated for asthma. This study provides a global estimate of the burden of asthma in adults, and suggests that asthma continues to be a major public health concern worldwide. The high prevalence of smoking remains a major barrier to combating the global burden of asthma. While the highest prevalence rates were observed in resource-rich countries, resource-poor nations were also significantly affected, posing a barrier to development as it stretches further the demands of non-communicable diseases.
    BMC Public Health 03/2012; 12:204. · 2.08 Impact Factor
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    ABSTRACT: Cholinesterase inhibitors (ChEIs) are a mainstay treatment for individuals with dementia. ChEIs may worsen airflow obstruction because of their pro-cholinergic properties. The objective of this study was to evaluate the risk of serious pulmonary complications in the elderly with concomitant chronic obstructive pulmonary disease (COPD) and dementia who were receiving ChEIs. This was a population-based, cohort study conducted between 2003 and 2010 in residents of Ontario, Canada. Subjects were over the age of 66 years and had concomitant dementia and COPD, identified using linked administrative databases. Exposure to ChEIs was determined using a drug benefits database. The primary outcome was an emergency room (ER) visit or hospitalization for COPD. The risk difference at 60 days and the relative risk (RR) for study outcomes were estimated in the propensity score-matched sample. Of 266,840 individuals with COPD, 45,503 had a concomitant diagnosis of dementia. A total of 7166 unexposed subjects were matched to subjects newly exposed to ChEIs. New users of ChEIs were not at significantly higher risk of ER visits or hospitalizations for COPD (RR 0.90; 95% CI 0.76, 1.07) or COPD exacerbations (RR 1.02; 95% CI 0.91, 1.15). Furthermore, ER visits for any respiratory diagnoses were not increased among new users of ChEIs (RR 1.02; 95% CI 0.87, 1.19) when compared with non-users. Sub-group analyses were consistent with the main analysis. In a large cohort of elderly individuals with COPD and dementia, new users of ChEIs had a similar risk for adverse pulmonary outcomes as those who were not receiving ChEIs.
    Drugs & Aging 03/2012; 29(3):213-23. · 2.65 Impact Factor
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    ABSTRACT: To determine the association between large birth weight and the risk of developing asthma in early childhood. All single live births (n=687 194) born in Ontario between 1 April 1995 and 31 March 2001 were followed until their sixth birthday. Their birth weight was categorised as low (<2.5 kg), normal (2.5-4.5 kg), large (4.6-6.5 kg) or extremely large (>6.5 kg). Poisson regression analysis was used. Compared with normal-birth-weight infants, large-birth-weight infants (2.3% of total) had a slightly lower risk of developing asthma by age 6 after adjusting for confounders (adjusted RR 0.90, 95% CI 0.86 to 0.93). There was a trend towards increased risk of asthma among extremely large-birth-weight infants (RR 1.21, 95% CI 0.67 to 2.19). Contrary to previous reports, large birth weight was associated with a lower risk for asthma. Instead, a trend towards increased risk of asthma was observed among extremely large-birth-weight infants and interventions to reduce the incidence of extreme large birth weight may help reduce the risk of asthma.
    Archives of Disease in Childhood 02/2012; 97(2):169-71. · 3.05 Impact Factor

Publication Stats

182 Citations
240.59 Total Impact Points


  • 2008–2013
    • Institute for Clinical Evaluative Sciences
      Toronto, Ontario, Canada
  • 2002–2013
    • University of Toronto
      • • Institute of Health Policy, Management and Evaluation
      • • Department of Medicine
      Toronto, Ontario, Canada
  • 2009–2012
    • SickKids
      Toronto, Ontario, Canada
  • 2010
    • Sunnybrook Health Sciences Centre
      • Department of Evaluative Clinical Sciences
      Toronto, Ontario, Canada