The air quality health index and asthma morbidity: a population-based study.

BACKGROUND: Exposure to air pollution has been linked to the exacerbation of respiratory diseases. The Air Quality Health Index (AQHI), developed in Canada, is a new health risk scale for reporting air quality and advising risk reduction actions. OBJECTIVE: We used the AQHI to estimate the impact of air quality on asthma morbidity, adjusting for potential confounders. METHODS: Daily air pollutant measures were obtained from 14 regional monitoring stations in Ontario. Daily counts of asthma-attributed hospitalizations, emergency department (ED) visits, and outpatient visits were obtained from a provincial registry of 1.5 million patients with asthma. Poisson regression was used to estimate health services rate ratios (RRs) as a measure of association between the AQHI or individual pollutants and health services use. We adjusted for age, sex, season, year, and region of residence. RESULTS: The AQHI values were significantly associated with increased use of asthma health services on the same day and on the 2 following days, depending on the specific outcome assessed. A 1-unit increase in the AQHI was associated with a 5.6% increase in asthma outpatient visits (RR = 1.056; 95% CI: 1.053, 1.058) and a 2.1% increase in the rate of hospitalization (RR = 1.021; 95% CI: 1.014, 1.028) on the same day and with a 1.3% increase in the rate of ED visits (RR = 1.013; 95% CI: 1.010, 1.017) after a 2-day lag. CONCLUSIONS: The AQHI values were significantly associated with the use of asthma-related health services. Timely AQHI health risk advisories with integrated risk reduction messages may reduce morbidity associated with air pollution in patients with asthma.

Results from a community-based program evaluating the effect of changing smoking status on asthma symptom control.

BACKGROUND: Cigarette smoking has been associated with accelerated decline in lung function, increased health services use and asthma severity in patients with asthma. Previous studies have provided insight into how smoking cessation improves lung function among asthma patients, however, fail to provide measurable asthma symptom-specific outcomes after smoking cessation. The objective of this study was to measure the effect of changing smoking status on asthma symptom control and health services use in adults with asthma. METHODS: The study was conducted in eight primary care practices across Ontario, Canada participating in a community-based, participatory, and evidence-based Asthma Care Program. Patients aged 18 to 55 identified with physician-diagnosed mild to moderate asthma were recruited. In addition to receiving clinical asthma care, participants were administered a questionnaire at baseline and 12-month follow-up visits to collect information on demographics, smoking status, asthma symptoms and routine health services use. The effect of changing smoking status on asthma symptom control was compared between smoking groups using Chi-square and Fisher's exact tests where appropriate. Mixed effect models were used to measure the impact of the change in smoking status on asthma symptom and health services use while adjusting for covariates. RESULTS: This study included 519 patients with asthma; 11% of baseline smokers quit smoking while 4% of baseline non-smokers started smoking by follow-up. Individuals who quit smoking had 80% lower odds of having tightness in the chest (Odds ratio (OR) = 0.21, 95% CI: 0.06, 0.82) and 76% lower odds of night-time symptoms (OR = 0.24, 95% CI: 0.07, 0.85) compared to smokers who continued to smoke. Compared to those who remained non-smokers, those who had not been smoking at baseline but self-reported as current smoker at follow-up had significantly higher odds of chest tightness (OR = 1.36, 95% CI: 1.10, 1.70), night-time symptoms (OR = 1.55, 95% CI: 1.09, 2.20), having an asthma attack in the last six months (OR = 1.43, 95% CI: 1.17, 1.75) and visiting a walk-in clinic for asthma (OR = 4.57, 95% CI: 1.44, 14.49). CONCLUSIONS: This study provides practitioners measurable and clinically important findings that associate smoking cessation with improved asthma control. Health practitioners and asthma programs can use powerful education messages to emphasize the benefits of smoking cessation as a priority to current smokers.

Is large birth weight associated with asthma risk in early childhood?

OBJECTIVE: To determine the association between large birth weight and the risk of developing asthma in early childhood. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

Feasibility of a provincial voluntary reporting system for work-related asthma in Ontario.

OBJECTIVE: The Ontario Work-Related Asthma Surveillance System: Physician Reporting (OWRAS) Network was established in 2007 to estimate the prevalence of work-related asthma (WRA) in Ontario, and to test the feasibility of collecting data for cases of WRA from physicians voluntarily. METHODS: More than 300 respirologists, occupational medicine physicians, allergists and primary care providers in Ontario were invited to participate in monthly reporting of WRA cases by telephone, postal service or e-mail. RESULTS: Since 2007, 49 physicians have registered with the OWRAS Network and, to date, have reported 34 cases of occupational asthma and 49 cases of work-exacerbated asthma. Highly reactive chemicals were the most frequently reported suspected causative agent of the 108 suspected exposures reported. CONCLUSION: Despite the challenge of enlisting a representative sample of physicians in Ontario willing to report, the OWRAS Network has shown that it is feasible to implement a voluntary reporting system for WRA; however, its long-term sustainability is currently unknown.

Evidence-based performance indicators of primary care for asthma: a modified RAND Appropriateness Method.

PURPOSE: To develop evidence-based performance indicators that measure the quality of primary care for asthma. DATA SOURCES: Cochrane Database of Systematic Reviews, MEDLINE, EMBASE and CINAHL for peer-reviewed articles published in 1998-2008 and five national/global asthma management guidelines. STUDY SELECTION: Articles with a focus on current asthma performance indicators recognized or used in community and primary care settings. Data extraction Modified RAND Appropriateness METHOD: was used. The work described herein was conducted in Canada in 2008. Five clinician experts conducted the systematic literature review. Asthma-specific performance indicators were developed and the strength of supporting evidence summarized. A survey was created and mailed to 17 expert panellists of various disciplines, asking them to rate each indicator using a 9-point Likert scale. Percentage distribution of the Likert scores were generated and given to the panellists before a face-to-face meeting, which was held to assess consensus. At the meeting, they ranked all indicators based on their reliability, validity, availability and feasibility. RESULTS: Literature search yielded 1228 articles, of which 135 were used to generate 45 performance indicators in five domains: access to care, clinical effectiveness, patient centeredness, system integration and coordination and patient safety. The top five ranked indicators were: Asthma Education from Certified Asthma Educator, Pulmonary Function Monitoring, Asthma Control Monitoring, Controller Medication Use and Asthma Control. CONCLUSION: The top 15 ranked indicators are recommended for implementation in primary care to measure asthma care delivery, respiratory health outcomes and establish benchmarks for optimal health service delivery over time and across populations.

Can children with spina bifida and muscular dystrophy participate in their own health status evaluations?

BACKGROUND: The outcomes movement has emphasized the importance of the patient in evaluating treatment outcome. However, concern has been raised about the ability of children, particularly those with multisystem disease, to evaluate their disability. PURPOSE: To determine whether children with spina bifida and muscular dystrophy and their parents agree when asked about the relative difficulty of daily activities and the severity of symptoms experienced by the child. METHODS: First, a list of symptoms and activity restrictions was generated from the literature, clinicians, and interviews with families with spina bifida and muscular dystrophy. Second, another group of parents and children with spina bifida (with hip dislocation or scoliosis) and with muscular dystrophy (with scoliosis), including those before and after surgery, independently rated the severity and importance of their objective and subjective complaints. RESULTS: The correlation between parents and their children was high for both objective (median Spearman's = 0.70; standard deviation [SD] = ±0.17; range = -0.05-1.00) and subjective (median Spearman's = 0.76; SD = ±0.14; range = 0.13-1.00) complaints, with an overall excellent level of agreement (Kappa = 0.75; 95% confidence interval [CI]: 0.73, 0.76). CONCLUSION: Children with spina bifida and muscular dystrophy are capable of understanding and assessing their disability.

What is the lifetime risk of physician-diagnosed asthma in Ontario, Canada?

RATIONALE: Asthma is the most common chronic respiratory disease in Canada. The estimates of risk of developing asthma may help researchers and health planners set research agendas, predict the burden of asthma on society, and target the at-risk population for asthma prevention, management, and control. OBJECTIVES: To estimate the lifetime risk of physician-diagnosed asthma. METHODS: All individuals aged 0-79 years living in Ontario, Canada on April 1, 1996 who had not been diagnosed with asthma were monitored for 11 years until March 31, 2007. They were censored when they were diagnosed with asthma, turned age 80 years, or died. The lifetime risk (from birth to age 79 yr) of physician-diagnosed asthma was calculated by a modified survival analysis technique. Results were stratified by sex, rurality, and neighborhood income. MEASUREMENTS AND MAIN RESULTS: Overall, the lifetime risk of physician-diagnosed asthma was 33.9%. Whereas the overall lifetime risk was higher in females (35.0 vs. 32.9%; P < 0.001), the cumulative risk was higher in males in early years. The lifetime risk was higher in individuals living in urban areas (34.5 vs. 30.1%; P < 0.001) or low-income neighborhoods (35.0% in the lowest income quintile vs. 32.2% in the highest; P < 0.001). CONCLUSIONS: Our estimated overall lifetime risk indicates that one of every three individuals in Ontario, Canada has physician-diagnosed asthma during one's lifetime.

How much do health care providers value a community-based asthma care program? A survey to collect their opinions on the utilities of and barriers to its uptake.

BACKGROUND: A comprehensive asthma care program (ACP) based on Canadian Asthma Consensus Guidelines was implemented in 8 primary care sites in Ontario, Canada. A survey was distributed to health care providers' (HCPs) to collect their opinions on the utilities of and barriers to the uptake of the ACP. METHODS: A 39-item self-administered survey was mailed to 184 HCPs and support staff involved in delivering the ACP at the end of implementation. The items were presented in mixed formats with most items requiring responses on a five-point Likert scale. Distributions of responses were analyzed and compared across types of HCPs and sites. RESULTS: Of the 184 surveys distributed, 108 (59%) were returned, and of that, 83 were completed by HCPs who had clinical contact with the patients. Overall, 95% of the HCPs considered the ACP useful for improving asthma care management. Most HCPs favored using the asthma care map (72%), believed it decreased uncertainties and variations in patient management (91%), and considered it a convenient and reliable source of information (86%). The most commonly reported barrier was time required to complete the asthma care map. Over half of the HCPs reported challenges to using spirometry, while almost 40% identified barriers to using the asthma action plan. CONCLUSION: Contrary to the notion that physicians believe that guidelines foster cookbook medicine, our study showed that HCPs believed that the ACP offered an effective and reliable approach for enhancing asthma care and management in primary care.

Can a community evidence-based asthma care program improve clinical outcomes?: a longitudinal study.

RATIONALE: Asthma is associated with significant morbidity. Previous studies highlight significant variations in asthma management approaches within primary care settings where the adoption of published asthma guidelines is typically suboptimal. OBJECTIVE: To determine whether the implementation of an evidence-based asthma care program in community primary care settings leads to improved clinical outcomes in asthma patients. METHODS, MEASUREMENTS, AND MAIN RESULTS: A community-based participatory research project was implemented at 8 primary care practices across Ontario, Canada, consisting of elements based on the Canadian Asthma Consensus Guidelines (asthma care map, program standards, management flow chart and action plan). A total of 1408 patients aged 2-55 years participated. Conditional logistic regression analyses were used to calculate the odds ratios (OR) comparing baseline to follow-up while adjusting for age, gender, socioeconomic status and other covariates. At 12-month follow-up, there were statistically significant reductions in self-reported asthma exacerbations from 77.8% to 54.5% [OR = 0.35; 95% confidence interval (CI): 0.28-0.43]; emergency room visits due to asthma from 9.9% to 5.5% (OR = 0.47; 95% CI: 0.32-0.62); school absenteeism in children from 19.9% to 10.2% (OR = 0.37; 95% CI: 0.25-0.54); productivity loss in adults from 12.0% to 10.3% (OR = 0.49; 95% CI: 0.34-0.71); uncontrolled daytime asthma symptoms from 62.4% to 41.4% (OR = 0.34; 95% CI: 0.27-0.42); and uncontrolled nighttime asthma symptoms from 46.4% to 25.4% (OR = 0.29; 95% CI: 0.23-0.37). CONCLUSIONS: Development and implementation of a community-based primary care asthma care program led to risk reductions in exacerbations, symptoms, urgent health service use and productivity loss related to asthma.