Aerobic and resistance training do not influence plasma carnosinase content or activity in type 2 diabetes.

A particular allele of the carnosinase gene (CNDP1) is associated with reduced plasma carnosinase activity and reduced risk for nephropathy in diabetic patients. On the one hand, animal and human data suggest that hyperglycemia increases plasma carnosinase activity. On the other hand, we recently reported lower carnosinase activity levels in elite athletes involved in high-intensity exercise compared with untrained controls. Therefore, this study investigates whether exercise training and the consequent reduction in hyperglycemia can suppress carnosinase activity and content in adults with type 2 diabetes. Plasma samples were taken from 243 males and females with type 2 diabetes (mean age = 54.3 yr, SD = 7.1) without major microvascular complications before and after a 6-mo exercise training program [4 groups: sedentary control (n = 61), aerobic exercise (n = 59), resistance exercise (n = 63), and combined exercise training (n = 60)]. Plasma carnosinase content and activity, hemoglobin (Hb) A1c, lipid profile, and blood pressure were measured. A 6-mo exercise training intervention, irrespective of training modality, did not decrease plasma carnosinase content or activity in type 2 diabetic patients. Plasma carnosinase content and activity showed a high interindividual but very low intraindividual variability over the 6-mo period. Age and sex, but not Hb A1c, were significantly related to the activity or content of this enzyme. It can be concluded that the beneficial effects of exercise training on the incidence of diabetic complications are probably not related to a lowering effect on plasma carnosinase content or activity.

The Sedentary Time and Activity Reporting Questionnaire (STAR-Q): reliability and validity against doubly labeled water and 7-day activity diaries.

We determined measurement properties of the Sedentary Time and Activity Reporting Questionnaire (STAR-Q), which was designed to estimate past-month activity energy expenditure (AEE). STAR-Q validity and reliability were assessed in 102 adults in Alberta, Canada (2009-2011), who completed 14-day doubly labeled water (DLW) protocols, 7-day activity diaries on day 15, and the STAR-Q on day 14 and again at 3 and 6 months. Three-month reliability was substantial for total energy expenditure (TEE) and AEE (intraclass correlation coefficients of 0.84 and 0.73, respectively), while 6-month reliability was moderate. STAR-Q-derived TEE and AEE were moderately correlated with DLW estimates (Spearman's ρs of 0.53 and 0.40, respectively; P < 0.001), and on average, the STAR-Q overestimated TEE and AEE (median differences were 367 kcal/day and 293 kcal/day, respectively). Body mass index-, age-, sex-, and season-adjusted concordance correlation coefficients (CCCs) were 0.24 (95% confidence interval (CI): 0.07, 0.36) and 0.21 (95% CI: 0.11, 0.32) for STAR-Q-derived versus DLW-derived TEE and AEE, respectively. Agreement between the diaries and STAR-Q (metabolic equivalent-hours/day) was strongest for occupational sedentary time (adjusted CCC = 0.76, 95% CI: 0.64, 0.85) and overall strenuous activity (adjusted CCC = 0.64, 95% CI: 0.49, 0.76). The STAR-Q demonstrated substantial validity for estimating occupational sedentary time and strenuous activity and fair validity for ranking individuals by AEE.

Development and testing of a past year measure of sedentary behavior: the SIT-Q.

BACKGROUND: Most sedentary behavior measures focus on occupational or leisure-time sitting. Our aim was to develop a comprehensive measure of adult sedentary behavior and establish its measurement properties. METHOD: The SIT-Q was developed through expert review (n = 7), cognitive interviewing (n = 11) and pilot testing (n = 34). A convenience sample of 82 adults from Calgary, Alberta, Canada, participated in the measurement property study. Test-retest reliability was assessed by intraclass correlation coefficients (ICCs) comparing two administrations of the SIT-Q conducted one month apart. Convergent validity was established using Spearman's rho, by comparing the SIT-Q estimates of sedentary behaviour with values derived from a 7-Day Activity Diary. RESULTS: The SIT-Q exhibited good face validity and acceptability during pilot testing. Within the measurement property study, the ICCs for test-retest reliability ranged from 0.31 for leisure-time computer use to 0.86 for occupational sitting. Total daily sitting demonstrated substantial correlation (ICC = 0.65, 95% CI: 0.49, 0.78). In terms of convergent validity, correlations varied from 0.19 for sitting during meals to 0.76 for occupational sitting. For total daily sitting, estimates derived from the SIT-Q and 7 Day Activity Diaries were moderately correlated (ρ = 0.53, p < 0.01). CONCLUSION: The SIT-Q has acceptable measurement properties for use in epidemiologic studies.

Does metformin modify the effect on glycaemic control of aerobic exercise, resistance exercise or both?

AIMS/HYPOTHESIS: Some previous studies suggested that metformin might attenuate the effects of exercise on glycaemia or fitness. We therefore examined whether metformin use influenced changes in glycaemic control, fitness, body weight or waist circumference resulting from aerobic and/or resistance training in people with type 2 diabetes participating in an exercise intervention trial. METHODS: After a 4 week run-in period, participants from the Diabetes Aerobic and Resistance Exercise (DARE) trial were randomly assigned to 22 weeks of aerobic training alone, resistance training alone, combined aerobic and resistance exercise training or a waiting-list control group. Of the 251 randomised, 143 participants reported using metformin throughout the entire study period and 82 reported not using metformin at all. RESULTS: Compared with control, aerobic training led to a significant reduction in HbA1c in the metformin users (-0.57%, 95% CI -1.05, -0.10; -6.3 mmol/mol, 95% CI -11.5, -1.1) but not in the non-metformin users (-0.17, 95% CI -0.78, 0.43; -1.9 mmol/mol, 95% CI -8.5, 4.7). However, there were no significant differences in the changes in HbA1c (or fasting glucose) between metformin users and non-users in any of the exercise groups compared with control (p> 0.32 for all metformin by group by time interactions). Similarly, metformin did not affect changes in indicators of aerobic fitness, strength and body weight or waist circumference (p ≥ 0.15 for all metformin by group by time interactions). CONCLUSIONS/INTERPRETATION: Contrary to our hypothesis and to previous short-term studies, metformin did not significantly attenuate the benefits of exercise on glycaemic control or fitness.

The Resistance Exercise in Already Active Diabetic Individuals (READI) Randomized Clinical Trial.

CONTEXT: Resistance exercise training (strength training) and aerobic exercise training are both recommended for people with type 1 diabetes, but it is unknown whether adding resistance exercise provides incremental benefits in people with this condition who already perform aerobic exercise regularly. OBJECTIVE: This work aimed to evaluate the incremental effect of resistance training on glycated hemoglobin A1c (HbA1c), fitness, body composition, and cardiometabolic risk factors in aerobically active people with type 1 diabetes. METHODS: The Resistance Exercise in Already-active Diabetic Individuals (READI) trial (NCT00410436) was a 4-center, randomized, parallel-group trial. After a 5-week run-in period with diabetes management optimization, 131 aerobically active individuals with type 1 diabetes were randomly assigned to resistance exercise (n = 71, intervention-INT) or control (n = 60, CON) for 22 additional weeks. Both groups maintained their aerobic activities and were provided dietary counseling throughout. Exercise training was 3 times per week at community-based facilities. The primary outcome was HbA1c, and secondary outcomes included fitness (peak oxygen consumption, muscle strength), body composition (anthropometrics, dual-energy x-ray absorptiometry, computed tomography), and cardiometabolic risk markers (lipids, apolipoproteins). Assessors were blinded to group allocation. RESULTS: There were no significant differences in HbA1c change between INT and CON. Declines in HbA1c (INT: 7.75 ± 0.10% [61.2 ± 1.1 mmol/mol] to 7.55 ± 0.10% [59 ± 1.1 mmol/mol]; CON: 7.70 ± 0.11% [60.7 ± 1.2 mmol/mol] to 7.57 ± 0.11% [59.6 ± 1.3 mmol/mol]; intergroup difference in change -0.07 [95% CI, -0.31 to 0.18]). Waist circumference decreased more in INT than CON after 6 months (P = .02). Muscular strength increased more in INT than in CON (P < .001). There were no intergroup differences in hypoglycemia or any other variables. CONCLUSION: Adding resistance training did not affect glycemia, but it increased strength and reduced waist circumference, in aerobically active individuals with type 1 diabetes.

Age and androgen-deprivation therapy on exercise outcomes in men with prostate cancer.

PURPOSE: The purpose of this study is to examine the effects of age (≤ 65 years or >65 years) and androgen-deprivation therapy (ADT, presence or absence) as factors that may predict changes in body composition and fitness following a 24-week exercise program in prostate cancer patients. METHODS: One hundred twenty-one men were randomly allocated to either: (1) aerobic exercise (AE), (2) resistance exercise (RE), or (3) usual care (UC). Body composition was assessed by DXA. Aerobic fitness was assessed through a maximal treadmill test. Muscular strength was assessed by leg extension and bench press using the eight-repetition maximum test. Responses were compared between younger (≤ 65 years) and older (> 65 years) patients with or without ADT. RESULTS: There did not appear to be an interaction between age and ADT on body composition or fitness, nor were there any significant changes in body composition for participants ≤ 65 years. In participants aged >65 years, lean mass decreased in AE (p = 0.013) and UC (p = 0.006), but was preserved in RE. In participants receiving ADT, there was a decrease in lean mass in AE (p = 0.003) and UC (p < 0.001) but not in RE. The non-ADT group did not show any changes in body composition but did show improvements in muscular fitness following resistance training (p < 0.001). CONCLUSION: Changes in body composition and physical fitness following a 24-week exercise program in men with prostate cancer are not influenced by age and/or ADT. Resistance training appears to attenuate the age-related decrease in lean mass and increase in body fat in older patients with prostate cancer and those receiving ADT.

Characterization of intensive care unit acquired hyponatremia and hypernatremia following cardiac surgery.

PURPOSE: Although intensive care unit (ICU) acquired sodium disturbances are common in critically ill patients, few studies have examined sodium disturbances in patients following cardiac surgery. The objective of this study was to describe the epidemiology of ICU-acquired hyponatremia and hypernatremia in patients following cardiac surgery. METHODS: We identified 6,727 adults (> or =18 yr) who were admitted consecutively to a regional cardiovascular intensive care unit (CVICU) from January 1, 2000 to December 31, 2006 and were documented as having normal serum sodium levels (133 to 145 mmol.L(-1)) during the first day of ICU admission. ICU-acquired hyponatremia and hypernatremia were defined as a change in serum sodium concentration to <133 mmol.L(-1) or >145 mmol.L(-1), respectively, following ICU day one. RESULTS: A first episode of ICU-acquired hyponatremia and hypernatremia developed in 785 (12%) and 242 (4%) patients, respectively, (95% confidence interval [CI] 11-12% and 95% CI 3-4%, respectively), with a respective incidence density of 4.2 and 1.3 patients per 100 days of ICU admission (95% CI 4.0-4.5 and 95% CI 1.2-1.5). The incidence of ICU-acquired sodium disturbances varied according to the patients' demographic and clinical variables for both hyponatremia (age, diabetes, Acute Physiology and Chronic Health Evaluation [APACHE II] score, mechanical ventilation, length of ICU stay, serum glucose level, and serum potassium level) and hypernatremia (APACHE II score, mechanical ventilation, length of hospital stay prior to ICU admission, length of ICU stay, serum glucose level, and serum potassium level). Compared with patients with normal serum sodium levels, hospital mortality was increased in patients with ICU-acquired hyponatremia (1.6% vs 10%, respectively; P < 0.001) and ICU-acquired hypernatremia (1.6% vs 14%, respectively; P < 0.001). CONCLUSION: ICU-acquired hyponatremia and hypernatremia are common complications in critically ill patients following cardiac surgery. They are associated with patient demographic and clinical characteristics and an increased risk of hospital mortality.

Tracheostomy tube malposition in patients admitted to a respiratory acute care unit following prolonged ventilation.

BACKGROUND: Tracheostomy tube malposition is a barrier to weaning from mechanical ventilation. We determined the incidence of tracheostomy tube malposition, identified the associated risk factors, and examined the effect of malposition on clinical outcomes. METHODS: We performed a retrospective study on 403 consecutive patients with a tracheostomy who had been admitted to an acute care unit specializing in weaning from mechanical ventilation between July 1, 2002, and December 31, 2005. Bronchoscopy reports were reviewed for evidence of tracheostomy tube malposition (ie, > 50% occlusion of lumen by tissue). The main outcome parameters were the incidence of tracheostomy tube malposition; demographic, clinical, and tracheostomy-related factors associated with malposition; clinical response to correct the malposition; the duration of mechanical ventilation; the length of hospital stay; and mortality. RESULTS: Malpositioned tracheostomy tubes were identified in 40 of 403 patients (10%). The subspecialty of the surgical service physicians who performed the tracheostomy was most strongly associated with malposition. Thoracic and general surgeons were equally likely to have their patients associated with a malpositioned tracheostomy tube, while other subspecialty surgeons were more likely (odds ratio, 6.42; 95% confidence interval, 1.82 to 22.68; p = 0.004). Malpositioned tracheostomy tubes were changed in 80% of cases. Malposition was associated with prolonged mechanical ventilation posttracheostomy (median duration, 25 vs 15 d; p = 0.009), but not with increased hospital length of stay or mortality. CONCLUSION: Tracheostomy tube malposition appears to be a common and important complication in patients who are being weaned from mechanical ventilation. Surgical expertise may be an important factor that impacts this complication.

The epidemiology of intensive care unit-acquired hyponatraemia and hypernatraemia in medical-surgical intensive care units.

INTRODUCTION: Although sodium disturbances are common in hospitalised patients, few studies have specifically investigated the epidemiology of sodium disturbances in the intensive care unit (ICU). The objectives of this study were to describe the incidence of ICU-acquired hyponatraemia and hypernatraemia and assess their effects on outcome in the ICU. METHODS: We identified 8142 consecutive adults (18 years of age or older) admitted to three medical-surgical ICUs between 1 January 2000 and 31 December 2006 who were documented to have normal serum sodium levels (133 to 145 mmol/L) during the first day of ICU admission. ICU acquired hyponatraemia and hypernatraemia were respectively defined as a change in serum sodium concentration to below 133 mmol/L or above 145 mmol/L following day one in the ICU. RESULTS: A first episode of ICU-acquired hyponatraemia developed in 917 (11%) patients and hypernatraemia in 2157 (26%) patients with an incidence density of 3.1 and 7.4 per 100 days of ICU admission, respectively, during 29,142 ICU admission days. The incidence of both ICU-acquired hyponatraemia (age, admission diagnosis, Acute Physiology and Chronic Health Evaluation (APACHE) II score, length of ICU stay, level of consciousness, serum glucose level, body temperature, serum potassium level) and ICU-acquired hypernatraemia (baseline creatinine, APACHE II score, mechanical ventilation, length of ICU stay, body temperature, serum potassium level, level of care) varied according to patients' characteristics. Compared with patients with normal serum sodium levels, hospital mortality was increased in patients with ICU-acquired hyponatraemia (16% versus 28%, p < 0.001) and ICU-acquired hypernatraemia (16% versus 34%, p < 0.001). CONCLUSIONS: ICU-acquired hyponatraemia and hypernatraemia are common in critically ill patients and are associated with increased risk of hospital mortality.

Health-related quality of life after cardiac surgery.

Health-related quality of life (HRQOL) assessments are designed to reflect a patient's perspective of how a disease has affected their overall health status. Patient-centered outcomes are of value both for risk assessment and as an outcome measure. Strategies for analyzing HRQOL data are inconsistent primarily because the data frequently do not meet underlying assumptions of traditional methods for statistical analyses and require a careful analytic approach.

Estimating the current and future cancer burden in Canada: methodological framework of the Canadian population attributable risk of cancer (ComPARe) study.

INTRODUCTION: The Canadian Population Attributable Risk of Cancer project aims to quantify the number and proportion of cancer cases incident in Canada, now and projected to 2042, that could be prevented through changes in the prevalence of modifiable exposures associated with cancer. The broad risk factor categories of interest include tobacco, diet, energy imbalance, infectious diseases, hormonal therapies and environmental factors such as air pollution and residential radon. METHODS AND ANALYSIS: Using a national network, we will use population-attributable risks (PAR) and potential impact fractions (PIF) to model both attributable (current) and avoidable (future) cancers. The latency periods and the temporal relationships between exposures and cancer diagnoses will be accounted for in the analyses. For PAR estimates, historical exposure prevalence data and the most recent provincial and national cancer incidence data will be used. For PIF estimates, we will model alternative or 'counterfactual' distributions of cancer risk factor exposures to assess how cancer incidence could be reduced under different scenarios of population exposure, projecting incidence to 2042. DISSEMINATION: The framework provided can be readily extended and applied to other populations or jurisdictions outside of Canada. An embedded knowledge translation and exchange component of this study with our Canadian Cancer Society partners will ensure that these findings are translated to cancer programmes and policies aimed at population-based cancer risk reduction strategies.

Cancer incidence attributable to insufficient fibre consumption in Alberta in 2012.

BACKGROUND: Insufficient fibre consumption has been associated with a increased risk of colorectal cancer. The purpose of this study was to estimate the proportion and absolute number of cancers in Alberta that could be attributed to insufficient fibre consumption in 2012. METHODS: The number and proportion of colorectal cancers in Alberta attributable to insufficient fibre consumption were estimated using the population attributable risk. Relative risks were obtained from the World Cancer Research Fund's 2011 Continuous Update Project on colorectal cancer, and the prevalence of insufficient fibre consumption (< 23 g/d) was estimated using dietary data from Alberta's Tomorrow Project. Age- and sex-specific colorectal cancer incidence data for 2012 were obtained from the Alberta Cancer Registry. RESULTS: Between 66% and 67% of men and between 73% and 78% of women reported a diet with insufficient fibre consumption. Population attributable risk estimates for colorectal cancer were marginally higher in men, ranging from 6.3% to 6.8% across age groups, whereas in women they ranged from 5.0% to 5.5%. Overall, 6.0% of colorectal cancers or 0.7% of all cancers in Alberta in 2012 were estimated to be attributable to insufficient fibre consumption. INTERPRETATION: Insufficient fibre consumption accounted for 6.0% of colorectal cancers in Alberta in 2012. Increasing fibre consumption in Alberta has the potential to reduce to the future burden of colorectal cancer in the province.

Cancer incidence attributable to inadequate physical activity in Alberta in 2012.

BACKGROUND: Physical inactivity has been consistently associated with increased risk of colorectal, endometrial, breast (in postmenopausal women), prostate, lung and ovarian cancers. The objective of the current analysis was to estimate the proportion and absolute number of site-specific cancer cases attributable to inadequate physical activity in Alberta in 2012. METHODS: We used population attributable risks to estimate the proportion of each site-specific cancer attributable to inactivity. Relative risk estimates were obtained from the epidemiological literature, and prevalence estimates were calculated with the use of data from the Canadian Community Health Survey cycle 2.1 (2003). Respondents who acquired 1.5-2.9 kcal/kg per day and less than 1.5 kcal/kg per day of physical activity were classified as moderately active and inactive, respectively, and both levels were considered inadequate for mitigating cancer risks. We obtained age-, sex- and site-specific cancer incidence data from the Alberta Cancer Registry for 2012. RESULTS: About 59%-75% of men and 69%-78% of women did not engage in adequate physical activity. Overall, 13.8% of cancers across all associated cancers were estimated to be attributable to inadequate physical activity, representing 7.2% of all cancers diagnosed in Alberta in 2012. Suboptimal levels of physical activity had a greater impact among women: the proportion of all associated cancers attributable to inadequate physical activity was 18.3% for women and 9.9% for men. INTERPRETATION: A substantial proportion of cancer cases diagnosed in Alberta were estimated to be attributable to inadequate physical activity. With the high prevalence of physical inactivity among adults in the province, developing strategies to increase physical activity levels could have a notable impact on reducing future cancer burden in Alberta.

Cancer incidence attributable to excess body weight in Alberta in 2012.

BACKGROUND: Excess body weight has been consistently associated with colorectal, breast, endometrial, esophageal, gall bladder, pancreatic and kidney cancers. The objective of this analysis was to estimate the proportion of total and site-specific cancers attributable to excess body weight in adults in Alberta in 2012. METHODS: We estimated the proportions of attributable cancers using population attributable risk. Risk estimates were obtained from recent meta-analyses, and exposure prevalence estimates were obtained from the Canadian Community Health Survey. People with a body mass index of 25.00-29.99 kg/m2 and of 30 kg/m2 or more were categorized as overweight and obese, respectively. RESULTS: About 14%-47% of men and 9%-35% of women in Alberta were classified as either overweight or obese; the proportion increased with increasing age for both sexes. We estimate that roughly 17% and 12% of obesity-related cancers among men and women, respectively, could be attributed to excess body weight in Alberta in 2012. The heaviest absolute burden in terms of number of cases was seen for breast cancer among women and for colorectal cancer among men. Overall, about 5% of all cancers in adults in Alberta in 2012 were estimated to be attributable to excess body weight in 2000-2003. INTERPRETATION: Excess body weight contributes to a substantial proportion of cases of cancers associated with overweight and obesity annually in Alberta. Strategies to improve energy imbalance and reduce the proportion of obese and overweight Albertans may have a notable impact on cancer incidence in the future.

Lung cancer incidence attributable to residential radon exposure in Alberta in 2012.

BACKGROUND: Radon is carcinogenic, and exposure to radon has been shown to increase the risk of lung cancer. The objective of this study was to quantify the proportion and number of lung cancer cases in Alberta in 2012 that could be attributed to residential radon exposure. METHODS: We estimated the population attributable risk of lung cancer for residential radon using radon exposure data from the Cross-Canada Survey of Radon Concentrations in Homes from 2009-2011 and data on all-cause and lung cancer mortality from Statistics Canada from 2008-2012. We used cancer incidence data from the Alberta Cancer Registry for 2012 to estimate the total number of lung cancers attributable to residential radon exposure. Estimates were also stratified by sex and smoking status. RESULTS: The mean geometric residential radon level in Alberta in 2011 was 71.0 Bq/m3 (geometric standard deviation 2.14). Overall, an estimated 16.6% (95% confidence interval 9.4%-29.8%) of lung cancers were attributable to radon exposure, corresponding to 324 excess attributable cancer cases. The estimated population attributable risk of lung cancer due to radon exposure was higher among those who had never smoked (24.8%) than among ever smokers (15.6%). However, since only about 10% of cases of lung cancer occur in nonsmokers, the estimated total number of excess cases was higher for ever smokers (274) than for never smokers (48). INTERPRETATION: With about 17% of lung cancer cases in Alberta in 2012 attributable to residential radon exposure, exposure reduction has the potential to substantially reduce Alberta's lung cancer burden. As such, home radon testing and remediation techniques represent important cancer prevention strategies.

Cancer incidence attributable to lifestyle and environmental factors in Alberta in 2012: summary of results.

BACKGROUND: Estimates of the proportion of cancer cases that can be attributed to modifiable risk factors are not available for Canada and, more specifically, Alberta. The purpose of this study was to estimate the total proportion of cancer cases in Alberta in 2012 that could be attributed to a set of 24 modifiable lifestyle and environmental risk factors. METHODS: We estimated summary population attributable risk estimates for 24 risk factors (smoking [both passive and active], overweight and obesity, inadequate physical activity, diet [inadequate fruit and vegetable consumption, inadequate fibre intake, excess red and processed meat consumption, salt consumption, inadequate calcium and vitamin D intake], alcohol, hormones [oral contraceptives and hormone therapy], infections [Epstein-Barr virus, hepatitis B and C viruses, human papillomavirus, Helicobacter pylori], air pollution, natural and artificial ultraviolet radiation, radon and water disinfection by-products) by combining population attributable risk estimates for each of the 24 factors that had been previously estimated. To account for the possibility that individual cancer cases were the result of a combination of multiple risk factors, we subtracted the population attributable risk for the first factor from 100% and then applied the population attributable risk for the second factor to the remaining proportion that was not attributable to the first factor. We repeated this process in sequential order for all relevant exposures. RESULTS: Overall, an estimated 40.8% of cancer cases in Alberta in 2012 were attributable to modifiable lifestyle and environmental risk factors. The largest proportion of cancers were estimated to be attributable to tobacco smoking, physical inactivity and excess body weight. The summary population attributable risk estimate was slightly higher among women (42.4%) than among men (38.7%). INTERPRETATION: About 41% of cancer cases in Alberta may be attributable to known modifiable lifestyle and environmental risk factors. Reducing the prevalence of these factors in the Alberta population has the potential to substantially reduce the provincial cancer burden.

Cancer incidence attributable to air pollution in Alberta in 2012.

BACKGROUND: The International Agency for Research on Cancer has classified outdoor air pollution (fine particulate matter [PM2.5]) as a Group 1 lung carcinogen in humans. We aimed to estimate the proportion of lung cancer cases attributable to PM2.5 exposure in Alberta in 2012. METHODS: Annual average concentrations of PM2.5 in 2011 for 22 communities across Alberta were extracted from the Clean Air Strategic Alliance Data Warehouse and were population-weighted across the province. Using 7.5 µg/m3 and 3.18 µg/m3 as the annual average theoretical minimum risk concentrations of PM2.5, we estimated the proportion of the population above this cut-off to determine the population attributable risk of lung cancer due to PM2.5 exposure. RESULTS: The mean population-weighted concentration of PM2.5 for Alberta in 2011 was 10.03 µg/m3. We estimated relative risks of 1.02 and 1.06 for theoretical minimum risk PM2.5 concentration thresholds of 7.5 µg/m3 and 3.18 µg/m3, respectively. About 1.87%-5.69% of incident lung cancer cases in Alberta were estimated to be attributable to PM2.5 exposure. INTERPRETATION: Our estimate of attributable burden is low compared to that reported in studies in other areas of the world owing to the relatively low levels of PM2.5 recorded in Alberta. Reducing PM2.5 emissions in Alberta should continue to be a priority to help decrease the burden of lung cancer in the population.

Impact of prosthesis-patient size on functional recovery after aortic valve replacement.

BACKGROUND: Prosthesis-patient size mismatch results when an implanted prosthetic aortic valve is of insufficient size for a patient's body surface area. The relation between prosthesis-patient size and functional capacity and adverse postoperative outcome is inconsistent. Our objectives were to examine the impact of valve replacement, continuous prosthesis-patient size, and other factors on functional recovery after aortic valve replacement (AVR) with the Duke Activity Status Index (DASI). METHODS AND RESULTS: From June 15, 1995, through May 14, 1998, 1108 patients underwent AVR after completing a DASI survey. Of these, 1014 completed a postoperative DASI survey at an average of 8.3 months postoperatively. Logistic ordinal regression was used to examine the influence of demographic variables, comorbidities, baseline DASI scores, indexed valve orifice area, standardized orifice size, and postoperative morbid events on postoperative DASI. There was overall improvement in postoperative functional recovery reflected by median preoperative and postoperative DASI scores of 29 and 46, P<0.001, respectively. Neither indexed orifice area, P=0.94, nor standardized orifice size, P=0.96, was associated with functional recovery. Female sex, increasing age, elevated serum creatinine, increased central venous pressure, and red blood cell transfusion were factors associated with poor postoperative functional recovery. CONCLUSIONS: A majority of patients report improvement in functional quality of life early after AVR. Similar functional recovery was demonstrated for patients along the full spectrum of valve sizes indexed to body size, even for values considered to represent severe mismatch for patient size. Factors other than prosthesis-patient size influence functional quality of life early after AVR.

Barriers and facilitators of Canadian quality and safety teams: a mixed-methods study exploring the views of health care leaders.

BACKGROUND: Health care organizations are utilizing quality and safety (QS) teams as a mechanism to optimize care. However, there is a lack of evidence-informed best practices for creating and sustaining successful QS teams. This study aimed to understand what health care leaders viewed as barriers and facilitators to establishing/implementing and measuring the impact of Canadian acute care QS teams. METHODS: Organizational senior leaders (SLs) and QS team leaders (TLs) participated. A mixed-methods sequential explanatory design included surveys (n=249) and interviews (n=89). Chi-squared and Fisher's exact tests were used to compare categorical variables for region, organization size, and leader position. Interviews were digitally recorded and transcribed for constant comparison analysis. RESULTS: Five qualitative themes overlapped with quantitative data: (1) resources, time, and capacity; (2) data availability and information technology; (3) leadership; (4) organizational plan and culture; and (5) team composition and processes. Leaders from larger organizations more often reported that clear objectives and physician champions facilitated QS teams (p<0.01). Fewer Eastern respondents viewed board/senior leadership as a facilitator (p<0.001), and fewer Ontario respondents viewed geography as a barrier to measurement (p<0.001). TLs and SLs differed on several factors, including time to meet with the team, data availability, leadership, and culture. CONCLUSION: QS teams need strong, committed leaders who align initiatives to strategic directions of the organization, foster a quality culture, and provide tools teams require for their work. There are excellent opportunities to create synergy across the country to address each organization's quality agenda.

Cancer incidence attributable to tobacco in Alberta, Canada, in 2012.

BACKGROUND: Strong and consistent epidemiologic evidence shows that tobacco smoking causes cancers at various sites. The purpose of this study was to quantify the proportion and total number of site-specific cancers in Alberta attributable to tobacco exposure. METHODS: The proportion of incident cancer cases attributable to active and passive tobacco exposure in Alberta was estimated with population attributable risks. Data from the Canadian Community Health Survey (CCHS) for 2000-2007 were used to estimate prevalence of active (current or former smoker) and passive (second-hand smoke) tobacco exposure in Alberta. RESULTS: According to the 2000/01 CCHS, 29.1% and 38.6% of Albertans were estimated to be current and former smokers, respectively. According to the 2003 CCHS, 23.7% of Albertans who had never smoked reported regular second-hand exposure to tobacco. Population attributable risk estimates for tobacco-related cancer sites ranged from about 4% for ovarian cancer to 74% for laryngeal cancer. About 5% of incident lung cancers in men and women who never smoked could be attributed to passive tobacco exposure. Overall, 37.0% of tobacco-related cancers in Alberta (or 15.7% of all cancers) were estimated to be attributable to active tobacco smoking in 2012. INTERPRETATION: A notable proportion of cancers associated with tobacco use were estimated to be attributable to active smoking in Alberta. Strategies to reduce the prevalence of active tobacco smoking in Alberta could have a considerable impact on future cancer incidence.