Progression from Asthma to Chronic Obstructive Pulmonary Disease. Is Air Pollution a Risk Factor?

RATIONALE: Individuals with asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS), have more rapid decline in lung function, more frequent exacerbations, and poorer quality of life than those with asthma or COPD alone. Air pollution exposure is a known risk factor for asthma and COPD; however, its role in ACOS is not as well understood. OBJECTIVES: To determine if individuals with asthma exposed to higher levels of air pollution have an increased risk of ACOS. METHODS: Individuals who resided in Ontario, Canada, aged 18 years or older in 1996 with incident asthma between 1996 and 2009 who participated in the Canadian Community Health Survey were identified and followed until 2014 to determine the development of ACOS. Data on exposures to fine particulate matter (PM2.5) and ozone (O3) were obtained from fixed monitoring sites. Associations between air pollutants and ACOS were evaluated using Cox regression models. MEASUREMENTS AND MAIN RESULTS: Of the 6,040 adults with incident asthma who completed the Canadian Community Health Survey, 630 were identified as ACOS cases. Compared with those without ACOS, the ACOS population had later onset of asthma, higher proportion of mortality, and more frequent emergency department visits before COPD diagnosis. The adjusted hazard ratios of ACOS and cumulative exposures to PM2.5 (per 10 µg/m(3)) and O3 (per 10 ppb) were 2.78 (95% confidence interval, 1.62-4.78) and 1.31 (95% confidence interval, 0.71-2.39), respectively. CONCLUSIONS: Individuals exposed to higher levels of air pollution had nearly threefold greater odds of developing ACOS. Minimizing exposure to high levels of air pollution may decrease the risk of ACOS.

Estimating Toronto's health services use for the 2015 Pan American and Parapan American Games.

AIMS: Ambient air temperature may exacerbate the burden of chronic diseases on Ontario's healthcare system during mass gathering events. This study aimed to estimate the impact of increasing temperature in July and August on health services use for chronic conditions in Ontario's Golden Horseshoe region during the 2015 Pan American and Parapan American Games, using environmental and health administrative data from previous years. METHOD: Negative binomial regression was used to calculate incidence risk ratios for same-day health services use (hospitalisations, emergency department visits, physician office visits) for all causes, asthma, asthma-related conditions, diabetes and hypertension associated with unit increases in daily maximum temperature from 1 May to 31 August in 2008-2010. Sensitivity analysis was performed to estimate the added burden of an increased population size, in order to model an influx of visitors during the Games. RESULTS: In July and August, on days with daily maximum temperatures of 35 °C compared to 25 °C, we estimated seeing 7,827 more physician office visits for all causes in Ontario's Golden Horseshoe region. The estimated relative increase in physician office visits for diabetes due to temperature alone was 8.4%. With an estimated 10% increase in population, the increase in physician office visits for all causes tripled to an estimated 23,590. CONCLUSION: Temperature was identified as a potential contributor to greater health services use during the Games, particularly for those living with diabetes. These results highlight the importance of strategic delivery of health services during mass gathering events, and suggest a role for educating at-risk individuals on prevention behaviours, particularly on very hot days.

Quality of asthma care under different primary care models in Canada: a population-based study.

BACKGROUND: Previous research has shown variations in quality of care and patient outcomes under different primary care models. The objective of this study was to use previously validated, evidence-based performance indicators to measure quality of asthma care over time and to compare quality of care between different primary care models. METHODS: Data were obtained for years 2006 to 2010 from the Ontario Asthma Surveillance Information System, which uses health administrative databases to track individuals with asthma living in the province of Ontario, Canada. Individuals with asthma (n=1,813,922) were divided into groups based on the practice model of their primary care provider (i.e., fee-for-service, blended fee-for-service, blended capitation). Quality of asthma care was measured using six validated, evidence-based asthma care performance indicators. RESULTS: All of the asthma performance indicators improved over time within each of the primary care models. Compared to the traditional fee-for-service model, the blended fee-for-service and blended capitation models had higher use of spirometry for asthma diagnosis and monitoring, higher rates of inhaled corticosteroid prescription, and lower outpatient claims. Emergency department visits were lowest in the blended fee-for-service group. CONCLUSIONS: Quality of asthma care improved over time within each of the primary care models. However, the amount by which they improved differed between the models. The newer primary care models (i.e., blended fee-for-service, blended capitation) appear to provide better quality of asthma care compared to the traditional fee-for-service model.