Geoff Anderson
University of Toronto
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The Lancet | 1998
Barbara Liu; Geoff Anderson; Nicole Mittmann; Teresa To; Tami Axcell; Neil H. Shear
BACKGROUND Tricyclic antidepressants (TCAs) are associated with an increased risk of falls and hip fractures in elderly people. Selective serotonin-reuptake inhibitors (SSRIs) are reported to be better tolerated than TCAs. We investigated the risk of hip fractures associated with SSRIs and TCAs. METHODS This case-control study used administrative healthcare data from the province of Ontario, Canada. 8239 cases-patients aged 66 years or older, treated in hospital between April, 1994, and March, 1995, for hip fracture-were each matched for age and sex to five controls. Logistic regression was used to calculate the odds ratio for hip fracture with adjustment for potential confounding effects produced by concomitant drug use and comorbidity. FINDINGS With participants who had no exposure to antidepressants as the reference category, the adjusted odds ratio for hip fracture was 2.4 (95% CI 2.0-2.7) for exposure to SSRIs, 2.2 (1.8-2.8) for exposure to secondary-amine TCAs, and 1.5 (1.3-1.7) for exposure to tertiary-amine TCAs. For all types of antidepressants, current use was associated with a higher risk of hip fracture than former use. The odds ratios for hip fracture were higher for new current users than for continuous current users in all three drug classes. The proportion of current use in the low-dose range was 22% for SSRIs, 50% for secondary-amine TCAs, and 58% for tertiary-amine TCAs. INTERPRETATION Exposure to any of the three classes of antidepressants is associated with a significant increase in the risk of hip fracture. Despite differences in dose distribution, this analysis suggests that SSRIs do not offer an advantage over TCAs in terms of risk of hip fracture.
Pediatrics | 2012
Eyal Cohen; Jay G. Berry; Ximena Camacho; Geoff Anderson; Walter P. Wodchis; Astrid Guttmann
BACKGROUND AND OBJECTIVE: Health care use of children with medical complexity (CMC), such as those with neurologic impairment or other complex chronic conditions (CCCs) and those with technology assistance (TA), is not well understood. The objective of the study was to evaluate health care utilization and costs in a population-based sample of CMC in Ontario, Canada. METHODS: Hospital discharge data from 2005 through 2007 identified CMC. Complete health system use and costs were analyzed over the subsequent 2-year period. RESULTS: The study identified 15 771 hospitalized CMC (0.67% of children in Ontario); 10 340 (65.6%) had single-organ CCC, 1063 (6.7%) multiorgan CCC, 4368 (27.6%) neurologic impairment, and 1863 (11.8%) had TA. CMC saw a median of 13 outpatient physicians and 6 distinct subspecialists. Thirty-six percent received home care services. Thirty-day readmission varied from 12.6% (single CCC without TA) to 23.7% (multiple CCC with TA). CMC accounted for almost one-third of child health spending. Rehospitalization accounted for the largest proportion of subsequent costs (27.2%), followed by home care (11.3%) and physician services (6.0%). Home care costs were a much larger proportion of costs in children with TA. Children with multiple CCC with TA had costs 3.5 times higher than children with a single CCC without TA. CONCLUSIONS: Although a small proportion of the population, CMC account for a substantial proportion of health care costs. CMC make multiple transitions across providers and care settings and CMC with TA have higher costs and home care use. Initiatives to improve their health outcomes and decrease costs need to focus on the entire continuum of care.
BMJ | 2011
Marci R Turner; Ximena Camacho; Hadas D. Fischer; Peter C. Austin; Geoff Anderson; Paula Rochon; Lorraine L. Lipscombe
Objective To quantify the effect of levothyroxine dose on risk of fractures in older adults. Design Nested case-control study. Setting Population based health databases, Ontario, Canada. Participants Adults aged 70 or more prescribed levothyroxine between 1 April 2002 and 31 March 2007 and followed for fractures until 31 March 2008. Cases were cohort members admitted to hospital for any fracture, matched with up to five controls from within the cohort who had not yet had a fracture. Main outcome measure Primary outcome was fracture (wrist or forearm, shoulder or upper arm, thoracic spine, lumbar spine and pelvis, hip or femur, or lower leg or ankle) in relation to levothyroxine use (current, recent past, remote). Risk among current users was compared between those prescribed high, medium, and low cumulative levothyroxine doses in the year before fracture. Results Of 213 511 prevalent levothyroxine users identified, 22 236 (10.4%) experienced a fracture over a mean 3.8 years of follow-up, 18 108 (88%) of whom were women. Compared with remote levothyroxine use, current use was associated with a significantly higher risk of fracture (adjusted odds ratio 1.88, 95% confidence interval 1.71 to 2.05), despite adjustment for numerous risk factors. Among current users, high and medium cumulative doses (>0.093 mg/day and 0.044-0.093 mg/day) were associated with a significantly increased risk of fracture compared with low cumulative doses (<0.044 mg/day): 3.45 (3.27 to 3.65) and 2.62 (2.50 to 2.76), respectively. Conclusion Among adults aged 70 or more, current levothyroxine treatment was associated with a significantly increased risk of fracture, with a strong dose-response relation. Ongoing monitoring of levothyroxine dose is important to avoid overtreatment in this population.
Journal of Vascular Surgery | 1998
Daryl S. Kucey; Beverley Bowyer; Karey Iron; Peter C. Austin; Geoff Anderson; Jack V. Tu
BACKGROUND The efficacy of carotid endarterectomy for selected patients has been evaluated with randomized controlled clinical trials. The generalizability of these studies to average surgical practice remains an important public health concern. OBJECTIVE The objective of the study was to determine the predictors of outcome after carotid endarterectomy on a regional basis. PATIENTS AND METHODS The study was designed as a retrospective cohort study and included all consecutive patients presented for carotid endarterectomy at the 8 University of Toronto-affiliated hospitals in the period from January 1, 1994, to December 31, 1996. The main outcome measure was 30-day postoperative stroke or death rate. RESULTS During the study interval, 1280 primary carotid endarterectomies were performed. The overall combined stroke and death rate was 6.3% for all patients who underwent endarterectomy (4.0% for patients who were asymptomatic). The significant predictors of poor outcome were the following: presenting symptoms (odds ratio, 1.74; 95% confidence interval [CI], 0.96, 3.12), low surgeon volume (<6 cases per year; odds ratio, 3.98; 95% CI, 1.65, 9.58), and left-sided surgery (odds ratio, 1.72; 95% CI, 1.07, 2.76). CONCLUSION These data suggest that adoption of the recommendations of the symptomatic carotid endarterectomy trials is appropriate. However, endarterectomy for asymptomatic lesions remains of uncertain benefit on a regional basis and must be individualized to the experience of the specific surgeon. The surgeon volume/outcome relationship that is identified in this study suggests a need for a minimum volume threshold for this procedure.
JAMA Internal Medicine | 2009
Lorraine L. Lipscombe; Linda E. Lévesque; Andrea Gruneir; Hadas D. Fischer; David N. Juurlink; Sudeep S. Gill; Nathan Herrmann; Janet E. Hux; Geoff Anderson; Paula A. Rochon
BACKGROUND Evidence suggests that there is an association between antipsychotic drugs and new-onset diabetes, but little is known about the risk of hyperglycemia among persons with preexisting diabetes. METHODS Using a nested case-control design and population-based health databases in Ontario, Canada, persons aged 66 years or older with diabetes who started treatment with an antipsychotic drug from April 1, 2002, to March 31, 2006, were followed up from treatment start until March 31, 2007. The cohort was subdivided into 3 groups: insulin-treated, oral hypoglycemic agent only-treated, and no diabetes treatment. We defined cases as patients hospitalized (emergency department visit or hospital admissions) for hyperglycemia. Each case was matched with up to 10 controls. We compared the likelihood of hyperglycemia among current users of atypical and typical antipsychotic agents with that among remote antipsychotic users (discontinued >180 days), based on prescriptions closest to event date. RESULTS Of 13 817 patients studied, 1515 (11.0%) were hospitalized for hyperglycemia. Current antipsychotic treatment was associated with a higher risk of hyperglycemia compared with remote antipsychotic use in all diabetes treatment groups (overall adjusted rate ratio, 1.50; 95% confidence interval, 1.29-1.74). The risk was increased among patients who were treated with atypical and typical antipsychotic agents and was extremely high among patients who were just starting treatment (only 1 prescription before event). CONCLUSIONS Among older patients with diabetes, the initiation of treatment with antipsychotic drugs was associated with a significantly increased risk of hospitalization for hyperglycemia (P < .001). The risk was particularly high during the initial course of treatment and was increased with the use of all antipsychotic agents.
Journal of Antimicrobial Chemotherapy | 2011
Nick Daneman; Andrea Gruneir; Alice Newman; Hadas D. Fischer; Susan E. Bronskill; Paula A. Rochon; Geoff Anderson; Chaim M. Bell
OBJECTIVES Evaluation and optimization of antibiotic use (antibiotic stewardship) is being increasingly promoted as a means to reduce antibiotic resistance, adverse events, treatment complications and costs within institutions. Our goal was to examine the prevalence of antibiotic use among long-term care facility residents and the extent of variability across these institutions. METHODS We conducted a population-based, point-prevalence study of antibiotic use among elderly individuals (n = 37,371) residing in long-term care facilities (n = 363 institutions) in Ontario between April and June 2009, using linked healthcare databases from Canadas largest province. Facilities were grouped into quintiles according to their mean antibiotic dispensing rates and variation was compared across quintiles. RESULTS There were 2190 (5.9%) long-term care residents receiving antibiotic prescriptions on the study date. The three most prevalent antibiotics were agents most commonly used for the treatment of urinary tract infections, including nitrofurantoin (365, 15.4%), trimethoprim/sulfamethoxazole (338, 14.3%) and ciprofloxacin (304, 12.8%). The majority of treatment courses were at least 10 days in duration (1482, 62.6%), and many exceeded 90 days (495, 20.9%), suggesting chronic prophylaxis. There was substantial variability in antibiotic use across facilities, with a 5-fold variation from the highest-use quintile (10.8%) to the lowest-use quintile (2.2%). This variation persisted after adjustment for multiple facility-level and resident-level factors, including demographic characteristics, healthcare utilization statistics, co-morbidity prevalence, functional status and device dependence. CONCLUSIONS Antibiotic use is common among long-term care residents, variable across institutions, and may benefit from focused antimicrobial stewardship interventions to standardize treatment indications and duration.
JAMA | 2014
Irfan A. Dhalla; Tara O’Brien; Dante Morra; Kevin E. Thorpe; Brian M. Wong; Rajin Mehta; David W. Frost; Howard Abrams; Françoise Ko; Patrick Van Rooyen; Chaim M. Bell; Andrea Gruneir; Geraint Lewis; Stacey Daub; Geoff Anderson; Gillian Hawker; Paula A. Rochon; Andreas Laupacis
IMPORTANCE Hospital readmissions are common and costly, and no single intervention or bundle of interventions has reliably reduced readmissions. Virtual wards, which use elements of hospital care in the community, have the potential to reduce readmissions, but have not yet been rigorously evaluated. OBJECTIVE To determine whether a virtual ward-a model of care that uses some of the systems of a hospital ward to provide interprofessional care for community-dwelling patients-can reduce the risk of readmission in patients at high risk of readmission or death when being discharged from hospital. DESIGN, SETTING, AND PATIENTS High-risk adult hospital discharge patients in Toronto were randomly assigned to either the virtual ward or usual care. A total of 1923 patients were randomized during the course of the study: 960 to the usual care group and 963 to the virtual ward group. The first patient was enrolled on June 29, 2010, and follow-up was completed on June 2, 2014. INTERVENTIONS Patients assigned to the virtual ward received care coordination plus direct care provision (via a combination of telephone, home visits, or clinic visits) from an interprofessional team for several weeks after hospital discharge. The interprofessional team met daily at a central site to design and implement individualized management plans. Patients assigned to usual care typically received a typed, structured discharge summary, prescription for new medications if indicated, counseling from the resident physician, arrangements for home care as needed, and recommendations, appointments, or both for follow-up care with physicians as indicated. MAIN OUTCOMES AND MEASURES The primary outcome was a composite of hospital readmission or death within 30 days of discharge. Secondary outcomes included nursing home admission and emergency department visits, each of the components of the primary outcome at 30 days, as well as each of the outcomes (including the composite primary outcome) at 90 days, 6 months, and 1 year. RESULTS There were no statistically significant between-group differences in the primary or secondary outcomes at 30 or 90 days, 6 months, or 1 year. The primary outcome occurred in 203 of 959 (21.2%) of the virtual ward patients and 235 of 956 (24.6%) of the usual care patients (absolute difference, 3.4%; 95% CI, -0.3% to 7.2%; P = .09). There were no statistically significant interactions to indicate that the virtual ward model of care was more or less effective in any of the prespecified subgroups. CONCLUSIONS AND RELEVANCE In a diverse group of high-risk patients being discharged from the hospital, we found no statistically significant effect of a virtual ward model of care on readmissions or death at either 30 days or 90 days, 6 months, or 1 year after hospital discharge. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01108172.
JAMA Internal Medicine | 2013
Nick Daneman; Andrea Gruneir; Susan E. Bronskill; Alice Newman; Hadas D. Fischer; Paula A. Rochon; Geoff Anderson; Chaim M. Bell
IMPORTANCE Given that most common bacterial infections can be treated with antibiotic courses of 7 or fewer days, reducing standard antibiotic treatment durations may be an avenue to curtailing antibiotic overuse in long-term care. OBJECTIVES To describe the variability in the duration of antibiotic treatment courses in long-term care across resident recipients and prescribing physicians and to determine whether this variability is influenced by prescriber preference. DESIGN AND SETTING Province-wide retrospective analysis of residents of Ontario, Canada, long-term care facilities in 2010. PARTICIPANTS All adults aged 66 years or older who received an incident treatment course with a systemic antibiotic while residing in an Ontario long-term care facility. MAIN OUTCOME MEASURE Antibiotic treatment duration was examined across residents and prescribing physicians. The proportion of a physicians treatment courses that exceeded 7 days was used to classify short-, average-, and long-duration prescribers. RESULTS Of 66 901 long-term care residents from 630 long-term care facilities, 50 061 (77.8%) received an incident antibiotic treatment course (with 51 540 antibiotic courses prescribed). The most commonly selected antibiotic treatment course was 7 days (in 21 136 courses [41.0%]), but 23 124 (44.9%) exceeded 7 days. Among the 699 physicians responsible for 20 or more antibiotic treatment courses, the median (interquartile range) proportion of treatment courses beyond 7 days was 43.5% (26.9%-62.9%) (range, 0%-97.1%). Twenty-one percent of prescribers had a higher-than-expected proportion of prescriptions beyond the 7-day threshold. Patient characteristics were similar across short-, average-, and long-duration prescribers. A mixed logistic model confirmed that prescribers were an important determinant of treatment duration (P < .001), with a relative odds of prolonged prescription of 3.84 for 75th vs 25th percentile prescribers. CONCLUSIONS AND RELEVANCE Antibiotic treatment courses in long-term care facilities are often prescribed for long durations, and this appears to be influenced by prescriber preference more than patient characteristics. Future trials should evaluate antibiotic stewardship interventions targeting prescriber preferences to systematically shorten average treatment durations to reduce the complications, costs, and resistance associated with antibiotic overuse.
Pediatrics | 2007
Astrid Guttmann; Brandon Zagorski; Peter C. Austin; Michael J. Schull; Asma Razzaq; Teresa To; Geoff Anderson
BACKGROUND. Emergency departments play an important role in the care of children with asthma. Emergency department return-visit rates provide a measure of the quality of acute asthma care. OBJECTIVE. Our goal was to describe the characteristics of children treated in emergency departments for asthma, the resources and asthma management strategies used by emergency departments, and their effect on return visits within 72 hours. DESIGN, SETTING, AND PATIENTS. We used a population-based cohort study that incorporated both comprehensive administrative heath and survey data from all 152 emergency departments in Ontario, Canada. We studied all 2- to 17-year-old children who had a visit to an emergency department for asthma from April 2003 to March 2005. RESULTS. A total of 32996 children (>9% of children with asthma in Ontario) had at least 1 visit to an emergency department for the care of asthma, and most of these visits (68.5%) were triaged as high acuity. The vast majority (148 of 152 [97%]) of emergency departments reported using at least 1 asthma management strategy, and 74% used 3 or more. The overall return-visit rate was 5.6%. Logistic regression models that accounted for the clustering of patients in emergency departments and controlled for patient and emergency department characteristics indicated that preprinted order sheets and access to a pediatrician for consultation were strategies significantly associated with a reduction in return visits. The 11 (17%) emergency departments that used both of these strategies had return visit rates of 4.4% compared with 6.9% in the 95 (63%) that used neither strategy. CONCLUSIONS. Emergency departments use a range of strategies to manage asthma in children. Preprinted order sheets and access to pediatricians are associated with important reductions in return-visit rates, and more emergency departments should consider using these strategies.
Annals of Neurology | 2012
Connie Marras; Andrea Gruneir; Paula A. Rochon; Xuesong Wang; Geoff Anderson; Jonathan M. Brotchie; Chaim M. Bell; Susan H. Fox; Peter C. Austin
A study was undertaken to test the association between dihydropyridine calcium channel blocker use and the time to important milestones of disease progression among patients with parkinsonism.