Developments in asthma incidence and prevalence in Alberta between 1995 and 2015

Abstract

Background Asthma is a chronic respiratory disease characterized by reversible bronchoconstriction and airway inflammation. According to Statistics Canada in 2014, 8.1% of Canadians aged 12 and older reported having asthma diagnosed by a health care professional. Therefore, in 2014 there were an estimated 274,661 persons with asthma in Alberta. Most epidemiological studies estimate prevalence and incidence using survey-based data, which has limitations. The Ontario Asthma Surveillance Information System (OASIS) group has developed and validated an algorithm for epidemiologic asthma studies using provincial health databases. In Alberta, there are some studies using provincial databases, but most are restricted to emergency department visits and do not represent the entire asthma population. Using the validated asthma definition for epidemiologic studies, we performed an analysis of the Alberta Health administrative databases to investigate and report province-wide asthma prevalence, incidence and mortality in Alberta from 1995 to 2015. Methods Data from administrative databases, provided by Alberta Health, was analyzed to determine age and sex specific prevalence, incidence and mortality of the asthma population. The population cohort was all individuals residing in the province of Alberta, ages 0 to 99 from 1995–2015. Kendall’s Tau coefficient test was used to ascertain whether the observed trends were statistically significant. Results Between 1995 and 2015, the age-standardized incidence of asthma decreased by more than 50% in both males and females. Prevalence, however, increased threefold over the 20 years (for both genders) from 3.9 to 12.3% (Tau = 1.00, p < 0.0001) in females and from 3.5 to 11.6% (Tau = 1.00, p < 0.0001) in males. Thus, in 2015 there were 496,927 people with asthma in Alberta. All-cause mortality in the asthma population decreased over time, in both females (Tau = − 0.71, p < 0.0001) and males (Tau = − 0.69, p = 0.0001). For the last several years, all-cause mortality was higher in those with asthma. There were ~ 7 deaths/1000 in the population with asthma versus ~ 5 deaths/1000 in those without asthma. Conclusions The incidence of asthma decreased in both females and males while prevalence continued to increase, although at a slower rate than previously. All-cause mortality in asthma patients was higher than in those without asthma, but both decreased over time.

Facilitators and barriers to the implementation of the Primary Care Asthma Paediatric Pathway: a qualitative analysis

“…Trial registration number This study was registered at clinicaltrials. gov on 25 June 2015; the registration number is: NCT02481037, https://clinicaltrials.gov/ct2/show/ NCT02481037?term=andrew+cave&cond=Asthma+in+ Children&cntry=CA&city=Edmonton&draw=2&rank=1 BACKGROUND An estimated 11%-15% of Canada's children have asthma; [1][2][3] and over half of these children experience poor disease control demonstrated by emergency department visits, hospital admissions, missed school days and low quality of life ratings. [3][4][5][6][7][8][9] Because of the significant burden of paediatric asthma, high quality, evidence-based national and international guidelines have been widely disseminated, including guidelines specific to primary care providers [10][11][12] However, the consistency of evidenced-based asthma care is variable, with less than 2% of clinicians able to provide all of the recommended care suggested by the guidelines and less than 5%…”