Brian Rowe

Publications of Brian Rowe

• Air pollution and emergency department visits for chest pain and weakness in Edmonton, Canada.

  Authors: Mieczysław Szyszkowicz, Brian Rowe

  International journal of occupational medicine and environmental health. 01/2010; 23(1):15-9.

  Chest pain or weakness can be first signal of health problems. Many studies demonstrate that these conditions can be related to air pollution. This work uses time-series data to investigate theChest pain or weakness can be first signal of health problems. Many studies demonstrate that these conditions can be related to air pollution. This work uses time-series data to investigate the association. This is a study of 68,714 emergency department (ED) visits for chest pain (ICD-9: 786) and of 66,092 ED visits for weakness (ICD-9: 780). The hierarchical method was applied to analyse the associations between daily counts of ED visits for chest pain and weakness (separately) and the levels of the air pollutants and meteorological variables. The counts of visits for all patients, males and females were analysed separately by whole period (I-XII), warm (IV-IX) and cold (X-III). The results are presented in the form of the excess risks associated with an increase in the interquartile range (IQR) for the pollutant. Chest pain: 2.4% (95% CI: 1.0-3.9) for CO, females, I-XII; 3.8% (95% CI: 0.0-7.8) for NO(2), males, IV-IX; 4.5% (95% CI: 0.9-8.3) for O(3) (1-day lagged), males, IV-IX; 2.8% (95% CI: 0.5-5.2), for PM(10), males, X-III; 2.0% (95% CI: 0.0-4.0), for SO(2), females, X-III; 2.1% (95% CI: 0.2-4.0) for PM(2.5), all, X-III. Weakness: 2.1% (95% CI: 0.4-3.7) for CO (2-day lagged), males, X-III; 3.4% (95% CI: 1.0-5.9) for NO(2) (2-day lagged), males, X-III; 2.4% (95% CI: 0.9-3.9) for SO(2), females, I-XII; 4.6% (95% CI: 1.0-8.2) for O(3) (1-day lagged), females, IV-IX. Obtained findings provide support for the hypothesis that ED visits for chest pain and weakness are associated with exposure to ambient air pollution.

• Emergency department visits for migraine and headache: a multi-city study.

  Authors: Mieczysław Szyszkowicz, Gilaad Kaplan, Eric Grafstein, Brian Rowe

  International journal of occupational medicine and environmental health. 10/2009;

  Objectives: We set out to examine associations between ambient air pollution concentrations and emergency department (ED) visits for migraine/headache in a multi-city study. Materials and Methods: WeObjectives: We set out to examine associations between ambient air pollution concentrations and emergency department (ED) visits for migraine/headache in a multi-city study. Materials and Methods: We designed a time-series study of 64 839 ED visits for migraine (ICD-9: 346) and of 68 495 ED visits for headache (ICD-9: 784) recorded at hospitals in five different cities in Canada. The data (days) were clustered according to the hierarchical structure (location, year, month, day of week). The generalised linear mixed models technique was applied to fit the logarithm of clustered daily counts of ED visits for migraine, and separately for headache, on the levels of air pollutants, after adjusting for meteorological conditions. The analysis was performed by sex (all, male, female) and for three different seasonal periods: whole (January-December), warm (April-September), and cold (October-March). Results: For female ED visits for migraine, positive associations were observed during the warm season for sulphur dioxide (SO2), and in the cold season for particulate matter (PM2.5) exposures lagged by 2-days. The percentage increase in daily visits was 4.0% (95% CI: 0.8-7.3) for SO2 mean level change of 4.6 ppb, and 4.6% (95% CI: 1.2,-8.1) for PM2.5 mean level change of 8.3 mug/m3. For male ED visits for headache, the largest association was obtained during the warm season for nitrogen dioxide (NO2), which was 13.5% (95% CI: 6.7-20.7) for same day exposure. Conclusions: Our findings support the associations between air pollutants and the number of ED visits for headache.

• Air pollution and emergency department visits for cardiac and respiratory conditions: a multi-city time-series analysis.

  Authors: David Stieb, Mieczyslaw Szyszkowicz, Brian Rowe, Judith Leech

  Environmental health : a global access science source. 07/2009; 8(1):25.

  ABSTRACT: BACKGROUND: Relatively few studies have been conducted of the association between air pollution and emergency department (ED) visits, and most of these have been based on a small number ofABSTRACT: BACKGROUND: Relatively few studies have been conducted of the association between air pollution and emergency department (ED) visits, and most of these have been based on a small number of visits, for a limited number of health conditions and pollutants, and only daily measures of exposure and response. METHODS: A time-series analysis was conducted on nearly 400,000 ED visits to 14 hospitals in seven Canadian cities during the 1990s and early 2000s. Associations were examined between carbon monoxide (CO), nitrogen dioxide (NO2), ozone (O3), sulfur dioxide (SO2), and particulate matter (PM10 and PM2.5), and visits for angina/myocardial infarction, heart failure, dysrhythmia/conduction disturbance, asthma, chronic obstructive pulmonary disease (COPD), and respiratory infections. Daily and 3-hourly visit counts were modeled as quasi-Poisson and analyses controlled for effects of temporal cycles, weather, day of week and holidays. RESULTS: 24-hour average concentrations of CO and NO2 lag 0 days exhibited the most consistent associations with cardiac conditions (2.1% (95% CI, 0.0-4.2%) and 2.6% (95% CI, 0.2-5.0%) increase in visits for myocardial infarction/angina per 0.7 ppm CO and 18.4 ppb NO2 respectively; 3.8% (95% CI, 0.7-6.9%) and 4.7% (95% CI, 1.2-8.4%) increase in visits for heart failure). Ozone (lag 2 days) was most consistently associated with respiratory visits (3.2% (95% CI, 0.3-6.2%), and 3.7% (95% CI, -0.5-7.9%) increases in asthma and COPD visits respectively per 18.4 ppb). Associations tended to be of greater magnitude during the warm season (April - September). In particular, the associations of PM10 and PM2.5 with asthma visits were respectively nearly three- and over fourfold larger vs. all year analyses (14.4% increase in visits, 95% CI, 0.2-30.7, per 20.6 ug/m3 PM10 and 7.6% increase in visits, 95% CI, 5.1-10.1, per 8.2 ug/m3 PM2.5). No consistent associations were observed between three hour average pollutant concentrations and same-day three hour averages of ED visits. CONCLUSIONS: In this large multicenter analysis, daily average concentrations of CO and NO2 exhibited the most consistent associations with ED visits for cardiac conditions, while ozone exhibited the most consistent associations with visits for respiratory conditions. PM10 and PM2.5 were strongly associated with asthma visits during the warm season.

• Ambient Sulphur Dioxide Exposure and Emergency Department Visits for Migraine in Vancouver, Canada.

  Authors: Mieczyslaw Szyszkowicz, Brian Rowe, Gilaad Kaplan

  International journal of occupational medicine and environmental health. 04/2009;

  Objectives: Ambient exposure to sulphur dioxide (SO2) has been previously associated with emergency department (ED) visits for migraine headaches. In the present study, the objective was to examineObjectives: Ambient exposure to sulphur dioxide (SO2) has been previously associated with emergency department (ED) visits for migraine headaches. In the present study, the objective was to examine the relationship between ED visits for migraine and ambient sulphur dioxide concentrations. Design and Methods: This was a time-series study of 1 059 ED visits for migraine (ICD-9: 346) recorded at a Vancouver hospital between 1999 and 2003 (1 520 days). Air pollution levels of SO2 were measured by fixed-site monitoring stations. The generalized linear mixed models technique was applied to regress daily counts of ED visits for migraine on the levels of the pollutant after adjusting for meteorological conditions: temperature and relative humidity. The analysis was stratified by season and gender. Results: Positive and statistically significant correlations were observed for SO2 exposure and ED visits for migraine for females during colder months (October-March). The percentage increase in daily visits was 16.8% (95% CI: 1.2-34.8) for a 4-day average (of daily mean concentrations) SO2 level, for an interquartile range (IQR) increase of 1.9 ppb. Conclusions: Our findings provide additional support for a consistent correlation between migraine headache and air pollution (SO2).

• Emergency department management of acute migraine in children in Canada: a practice variation study.

  Authors: Lawrence Richer, Lee Graham, Terry Klassen, Brian Rowe

  Headache. 05/2007; 47(5):703-10.

  OBJECTIVES: Evidence-based guidelines for the treatment of children with migraine are limited given the paucity of randomized controlled trials, especially in the emergency department (ED). OurOBJECTIVES: Evidence-based guidelines for the treatment of children with migraine are limited given the paucity of randomized controlled trials, especially in the emergency department (ED). Our objectives were to: (1) characterize the treatment of children with migraine in the ED; (2) determine whether treatment varies in pediatric versus mixed (pediatric and adult) EDs. METHODS: Children aged 5 to 17 years presenting to 4 regional emergency departments in Edmonton, Alberta, Canada during the 2003/2004 fiscal year with a diagnostic code of headache or migraine were selected. A standardized retrospective chart abstraction was performed and migraine or probable migraine cases were classified based on the International Classification of Headache Disorders II. RESULTS: Three hundred and eighty-two cases were identified of which 48.7% (n = 186/382) met sufficient criteria for migraine. No treatment was given in 44.2% (n = 169/382). Simple oral analgesics (23.3%; n = 89/182) and dopamine antagonists (metoclopramide and prochlorperazine; 20.7%; n = 79/182) were prescribed first-line most commonly. Opiate medications (5.5%), ketorolac (4.7%), dihydroergotamine (1%) were prescribed first-line infrequently. There was a significant difference in the management choices between pediatric and mixed adult/pediatric EDs (chi(2)= 19.695; df = 5; P= .001). The pediatric ED was more likely to prescribe a dopamine antagonist (12.9 vs 6.8%; P= .044) while the mixed adult/pediatric EDs were more likely to prescribe an opiate (28.1% vs 18.4%; P= .031). Children with migraine in all EDs were significantly more likely to receive drug therapy (68.3% vs 42.9%; P < .001) or a dopamine antagonist (32.3% vs 9.7%; P < .001). Polypharmacy (31.2%; n = 119/382) and neuroimaging (29.1%; n = 111/382) were common. Outcome was poorly documented overall. No adverse events were recorded. CONCLUSIONS: Significant variation in practice in the management of acute headaches in children was observed between mixed population and pediatric-only emergency physicians in the same city. Most children do not receive any drug therapy. Children presenting to the pediatric ED were significantly more likely to receive a dopamine antagonist while opiates were prescribed more commonly in the mixed ED. More clinical trials are required in children to clarify areas of clinical uncertainty on which evidence-based practice guidelines can be formed.

• Outdoor air pollution and emergency department visits for asthma among children and adults: A case-crossover study in northern Alberta, Canada

  Authors: Paul Villeneuve, Li Chen, Brian Rowe, Frances Coates

  Environmental Health: A Global Access Science Source. 01/2007;

  Abstract Background Recent studies have observed positive associations between outdoor air pollution and emergency department (ED) visits for asthma. However, few have examined the possibleAbstract Background Recent studies have observed positive associations between outdoor air pollution and emergency department (ED) visits for asthma. However, few have examined the possible confounding influence of aeroallergens, or reported findings among very young children. Methods A time stratified case-crossover design was used to examine 57,912 ED asthma visits among individuals two years of age and older in the census metropolitan area of Edmonton, Canada between April 1, 1992 and March 31, 2002. Daily air pollution levels for the entire region were estimated from three fixed-site monitoring stations. Similarly, daily levels of aeroallergens were estimated using rotational impaction sampling methods for the period between 1996 and 2002. Odds ratios and their corresponding 95% confidence intervals were estimated using conditional logistic regression with adjustment for temperature, relative humidity and seasonal epidemics of viral related respiratory disease. Results Positive associations for asthma visits with outdoor air pollution levels were observed between April and September, but were absent during the remainder of the year. Effects were strongest among young children. Namely, an increase in the interquartile range of the 5-day average for NO₂and CO levels between April and September was associated with a 50% and 48% increase, respectively, in the number of ED visits among children 2 – 4 years of age (p < 0.05). Strong associations were also observed with these pollutants among those 75 years of age and older. Ozone and particulate matter were also associated with asthma visits. Air pollution risk estimates were largely unchanged after adjustment for aeroallergen levels. Conclusion Our findings, taken together, suggest that exposure to ambient levels of air pollution is an important determinant of ED visits for asthma, particularly among young children and the elderly.

• Reviewer agreement trends from four years of electronic submissions of conference abstract

  Authors: Brian Rowe, Trevor Strome, Carol Spooner, Sandra Blitz, Eric Grafstein, Andrew Worster

  BMC Medical Research Methodology. 01/2006;

  Abstract Background The purpose of this study was to determine the inter-rater agreement between reviewers on the quality of abstract submissions to an annual national scientific meeting (CanadianAbstract Background The purpose of this study was to determine the inter-rater agreement between reviewers on the quality of abstract submissions to an annual national scientific meeting (Canadian Association of Emergency Physicians; CAEP) to identify factors associated with low agreement. Methods All abstracts were submitted using an on-line system and assessed by three volunteer CAEP reviewers blinded to the abstracts' source. Reviewers used an on-line form specific for each type of study design to score abstracts based on nine criteria, each contributing from two to six points toward the total (maximum 24). The final score was determined to be the mean of the three reviewers' scores using Intraclass Correlation Coefficient (ICC). Results 495 Abstracts were received electronically during the four-year period, 2001 – 2004, increasing from 94 abstracts in 2001 to 165 in 2004. The mean score for submitted abstracts over the four years was 14.4 (95% CI: 14.1–14.6). While there was no significant difference between mean total scores over the four years (p = 0.23), the ICC increased from fair (0.36; 95% CI: 0.24–0.49) to moderate (0.59; 95% CI: 0.50–0.68). Reviewers agreed less on individual criteria than on the total score in general, and less on subjective than objective criteria. Conclusion The correlation between reviewers' total scores suggests general recognition of "high quality" and "low quality" abstracts. Criteria based on the presence/absence of objective methodological parameters (i.e., blinding in a controlled clinical trial) resulted in higher inter-rater agreement than the more subjective and opinion-based criteria. In future abstract competitions, defining criteria more objectively so that reviewers can base their responses on empirical evidence may lead to increased consistency of scoring and, presumably, increased fairness to submitters.

• The use of noninvasive mechanical ventilation for the treatment of acute exacerbations of chronic obstructive pulmonary disease in Canada.

  Authors: Jennifer Drummond, Brian Rowe, Lawrence Cheung, Irvin Mayers

  Canadian respiratory journal : journal of the Canadian Thoracic Society. 05/2005; 12(3):129-33.

  BACKGROUND: Noninvasive mechanical ventilation (NIMV) is accepted as a life-saving treatment for patients presenting to the emergency department and other acute care settings with severeBACKGROUND: Noninvasive mechanical ventilation (NIMV) is accepted as a life-saving treatment for patients presenting to the emergency department and other acute care settings with severe exacerbations of chronic obstructive pulmonary disease (COPD). OBJECTIVES: It was hypothesized that there is marked national variability in the use of NIMV. Therefore, the use of NIMV for COPD exacerbations in urban centres across Canada was evaluated. METHODS: All Canadian hospitals affiliated with a university training program were surveyed, and a request for involvement in this survey was posted on the Canadian Society of Respiratory Therapy professional practice listserv. Survey information was received from all 33 sites (100%) that were contacted. RESULTS: Marked differences in the application of NIMV were identified across all regions in Canada, ranging from requiring extensive monitoring in the intensive care unit to application on a general internal medical unit with intermittent noninvasive blood pressure monitoring. There were sites that rarely used NIMV for COPD exacerbations and others where it was routine practice. CONCLUSIONS: NIMV is a life-saving treatment for acute exacerbations of COPD. Despite clear clinical evidence, its use has not penetrated throughout all the larger urban hospitals in Canada. This may be more problematic in sites without 24 h respiratory therapy support. There are barriers to the routine application of NIMV that can be overcome using established guidelines and available evidence.

• Systematic review: cardiac resynchronization in patients with symptomatic heart failure.

  Authors: Finlay A McAlister, Justin A Ezekowitz, Natasha Wiebe, Brian Rowe, Carol Spooner, Ellen Crumley, Lisa Hartling, Terry Klassen, William Abraham

  Annals of internal medicine. 10/2004; 141(5):381-90.

  BACKGROUND: Even with optimal pharmacotherapy, symptomatic heart failure is associated with substantial morbidity and mortality. PURPOSE: To determine the efficacy and safety of cardiacBACKGROUND: Even with optimal pharmacotherapy, symptomatic heart failure is associated with substantial morbidity and mortality. PURPOSE: To determine the efficacy and safety of cardiac resynchronization therapy in adults with advanced systolic heart failure. DATA SOURCES: The Cochrane Central Register of Controlled Trials (2002, volume 4), MEDLINE (1980-2003), EMBASE (1980-2003), other electronic databases, and U.S. Food and Drug Administration reports. We contacted primary study authors and device manufacturers, and we hand searched bibliographies of relevant papers and conference proceedings. STUDY SELECTION: Randomized, controlled clinical trials for efficacy and controlled trials plus prospective cohort studies for safety. DATA EXTRACTION: Two reviewers chose studies and extracted data independently; random-effects models were used for analyses. DATA SYNTHESIS: Nine trials were included in the efficacy review (3216 patients). All trial participants had reduced ejection fraction and prolonged QRS duration, and 85% had New York Heart Association (NYHA) class III or IV symptoms. Cardiac resynchronization therapy improved ejection fraction (weighted mean difference, 0.035 [95% CI, 0.015 to 0.055]), quality of life (weighted mean reduction in score on the Minnesota Living with Heart Failure Questionnaire, 7.6 points [CI, 3.8 to 11.5 points]), and function (58% vs. 37% of patients improved by at least 1 NYHA class). Heart failure hospitalizations were reduced by 32% (relative risk [RR], 0.68 [CI, 0.41 to 1.12]), with benefits most marked in patients with NYHA class III or IV symptoms at baseline (RR, 0.65 [CI, 0.48 to 0.88]; number needed to treat for benefit [NNT(B)], 12). All-cause mortality was reduced by 21% (RR, 0.79 [CI, 0.66 to 0.96]; NNT(B), 24), driven largely by reductions in death from progressive heart failure (RR, 0.60 [CI, 0.36 to 1.01]). Eighteen studies (total of 3701 patients with cardiac resynchronization devices) were included in the safety review. Implant success rate was 90% (CI, 89% to 91%), and 0.4% of patients died during implantation (CI, 0.2% to 0.7%). Over a median 6-month follow-up, leads dislodged in 9% of patients (CI, 7% to 10%) and mechanical malfunctions occurred in 7% (CI, 5% to 8%). LIMITATIONS: These trials enrolled only patients with heart failure with NYHA class III or IV symptoms despite medical therapy, a prolonged QRS duration, and reduced ejection fraction; in addition, experienced providers implanted the devices. Because all but one of these trials randomly assigned patients after device implantation, their results may overestimate the potential benefits of cardiac resynchronization. Finally, since few patients in these trials had bradyarrhythmias or atrial fibrillation, the role of cardiac resynchronization in such patients is uncertain. CONCLUSIONS: In selected patients with heart failure, cardiac resynchronization therapy improves functional and hemodynamic status, reduces heart failure hospitalizations, and reduces all-cause mortality.

• The inactivated trivalent split-virus influenza vaccine was safe in stable asthma.

  Authors: Brian Rowe

  ACP journal club. 137(1):18.