From: Clinical, economic, and humanistic burden of asthma in Canada: a systematic review
Reference/Study period | Data source | Study objective | Inclusion criteria | Asthma definition |
---|---|---|---|---|
Retrospective cohort studies | ||||
Sadatsafavi et al. 2010 [10] 1996 - 2000 | Administrative healthcare data | Determine direct medical costs of asthma-related healthcare in British Columbia | 5 to 55 years | Narrow: ICD-9 493.x Broad: visits for an asthma-related diagnosis; hospitalizations with asthma among the discharge diagnoses |
≥4 asthma prescriptions in 1 year | ||||
≥1 asthma hospitalization | ||||
≥2 physician visits for asthma | ||||
Blais et al. 2011 [18] 1998 - 2005 | RAMQ database, | Determine relationship between better use of LTRA and asthma exacerbations in children | 5-15 years | Moderate or severe asthma exacerbations - an ED visit for asthma, a hospital admission for asthma, or a dispensed short-course (14 days) prescription of oral corticosteroids |
Diagnosed asthma | ||||
Initiating (mono)therapy with ICS or LTRA | ||||
Rosychuk et al. 2010 [19] Apr 1999 to Mar 2005 | Provincial administrative healthcare databases | Describe the epidemiology of asthma presentations to EDs for 3 main regions in the province of Alberta | All people registered under the AHCIP at any time in a given year | ICD-9 code 493.x or ICD-10 code J45.x as the first or second diagnosis fields in the ACCS |
Crighton et al. 2001 [20] Apr 1, 1988 to Mar 31, 2000 | DAD database at CIHI, | Examine the seasonal patterns and trends of asthma hospitalizations in relation to age and gender | NR | ICD-9-CM code 493 |
Ungar et al. 2011 [21] Nov 1, 2000 to Mar 31, 2003 | Interview data linked to administrative healthcare data. | Identify factors associated with asthma exacerbation causing ED visits or hospitalizations related to health status, socioeconomic status (SES), and drug insurance | 1 to 18 years | Physician-diagnosed asthma; ICD-9 493 or ICD-10 J45 |
Disano et al. 2010 [22] 2003 - 2006 | DAD database from CIHI, INSQP Deprivation Index, Statistics Canada Community Profiles | Examine inequalities between SES groups with respect to rates of ACSC-hospitalizations | Acute care cases of 0 to 75 years; asthma in children for age <20 years | NR |
Blais et al. 2009 [18] 2002 - 2004 | RAMQ database | Compare the use of healthcare services between new users of budesonide/formoterol and F/S | Asthma patients aged 16 to 65 years ≥1 claim for combination therapy in 2002 or 2003 and no claims for combination therapy for ≥1 year prior to first claim | ICD-9 codes 493.0, 493.1, 493.9 |
Rowe et al. 2009 [23] 1 Apr 1999–31 Mar 2005 | ACCS and other provincial databases. | Describe the epidemiology of asthma presentations to EDs made by adults in the province of Alberta, Canada | Asthmatic individuals aged 18 years | ICD-9 493.x or ICD-10 J45.x |
To et al. 2008 [24] 1994 - 1998 | DAD database from CIHI, OHIP records, RPDB database | Describe the prevalence of asthma; all-cause mortality; physician visits and hospitalizations for asthma and all causes; and seasonal and geographical variation of healthcare utilization in children | Children aged 0 to 9 years | At least 1 asthma hospitalization or 2 asthma OHIP claims within 3 years |
Lemiere et al. 2007 [25] 2001 - 2004 | RAMQ database, WRA patients | Compare clinical characteristics and use of medical resources between subjects with OA, WEA, and WRA | NR | Physician-diagnosed asthma OA, WEA, and WRA |
To et al. 2007 [26] 1994 to 2006 | HMDB database from CIHI, OHIP records, RPDB database; | Examine and predict the persistence of childhood asthma | Children born in 1994 diagnosed with asthma before their 6th birthday, followed up until their 12th birthday | 1 asthma hospitalization or 2 asthma physician claims within 3 years prior to age 6 years (ICD-9 493 or ICD-10 J45). Persistent asthma - additional claims during follow-up Remission asthma - no additional claims |
Agha et al. 2007 [27] 1993 - 2001 | DAD database at CIHI, SES from the 1996 Census data | Examine socioeconomic disparities in ACS and non-ACS admissions among birth cohorts in a universal health insurance setting | Children born alive in Toronto during 1993–2001 | The most responsible diagnosis in the CIHI DAD DB |
Gershon et al. 2007 [2] 1994/95 to 2001/202 | DAD from CIHI, OHIP | Understand the burden of asthma | Asthma patients from ON, aged 0–39 years | 1 DAD hospitalization record or 2 OHIP claims for asthma in a 3-year period |
Lougheed et al. 2006 [28] 2001 - 2002 | CIHI | Assess regional differences in ED visit rates and hospitalizations for asthma | ED visits for asthma | ICD-10 code J45.x |
Dik et al. 2006 [29] 1985 - 1998 | Manitoba administrative healthcare data | Study 14-year trends in utilization of physician resources for asthma and compare them to trends for allergic rhinitis | NR | ICD-9-CM code 493 |
Sin et al. 2001 [30] FY 1992 - 1996 | CIHI, drug claims, physician billing, and mortality databases | Determine the impact of ICS on rehospitalization for asthma and all-cause mortality rates in elderly patients | Asthmatic patients, aged ≥65 years, who had been hospitalized with a most responsible diagnosis of asthma in the past 5 years | ICD-9 codes 493.0, 493.1, and 493.9 |
Prospective cohort studies | ||||
Rowe et al. 2010 [31] 2004 – 2005 | Interviews | Describe factors associated with admission to hospital for acute asthma after ED treatment | Patients aged 18 to 55 years diagnosed with asthma | Patient-reported |
Sin et al. 2003 [32] 1985, 1988 | AHCIP data, | Determine the relationship between SES and ED visits for asthma in a free access healthcare system. | Children born 1985 to 1988 followed for 10 years | ICD-9 code 493.x |
Ungar et al. 2001 [33] May - Oct 1995 | Telephone interviews at 1, 3, and 6 months, | Assess the cost of asthma care at the patient level in children from the perspectives of society, the Ontario Ministry of Health, and the patient. | Patients or caregivers filling prescriptions for bronchial inhalers | Probable asthma - a prescription for a bronchial inhaler medication in the last month (bronchodilator or corticosteroid) and reported experiencing shortness of breath, wheeze, or recurrent cough in the past |
Anis et al. 2000 [34] Sept 1, 1994 - Aug 31 1995 | Hospital ED, telephone interview for follow-up | Estimate the average direct cost of illness for 4 cardiorespiratory conditions | ED visitors who completed follow-up interviews | ED visit records |
Rowe et al. 2007 [23] 1996-1998 | Structured ED interview and telephone follow-up 2 weeks later | Compare ED asthma management and outcomesbetween Canada and US | Patients aged 2 to 54 years who presented with acute asthma in ED | NR |
Cross-sectional studies | ||||
Boulet et al. 2008 [35] April - August 2004, | Telephone survey | Assess the influence of current and former smoking on self-reported asthma control and healthcare use | Adults aged 18 to 54 years with physician-diagnosed asthma for ≥6 months | Patient-reported or physician-diagnosed asthma |
Klomp et al. 2008 [36] 2002/03 and 2003/04 | Health databases in Saskatchewan | Describe the quality of asthma care using a set of proposed quality indicators | Saskatchewan residents who had a valid health insurance number | Over 1-year period: ≥3 prescriptions for antiasthma drug or ≥2 physician claims (ICD-9 code 493) or ≥2 hospitalization claims (ICD-9 493.x or ICD-10 J45.x) or ≥1 claim for physician services or hospitalization for asthma plus ≥1 pharmacy claim for an antiasthma drug |
Iron et al. 2003 [37] 1994/1995 | CNPHS data, OHIP | Determine the association between demographics, access to care, SES, and need (comorbidities) with actual family physician costs | Survey respondents aged ≥25 years consenting to share HC# and responses with MOHLTC | Self-reported |
Anis et al. 2001 [38] 1995 | Ministry of Health administrative databases | Determine whether excessive use of SABA, in conjunction with underuse of ICS, would be a marker for poorly controlled asthma and excessive use of healthcare resources | Asthma patients aged 5 to 50 years for whom ≥1 prescription for a SABA was filled in 1995 | Patients filling SABA prescriptions; for hospitalizations, ICD-9 code 08 (diseases of the respiratory system) |
Baibergenova et al. 2005 [39] April 1, 2001 to March 31, 2004 | Examine the pattern and strength of seasonal fluctuations in ED visits due to asthma | Asthma patients with ED visits for asthma or status asthmaticus | ICD-9 code 493.x or ICD-10 J45.0–J45.9 | |
Lynd et al. 2004 [40] NR | Survey | Assess the association between SES and SABA use, controlling for asthma severity | Asthmatic patients aged 19 to 50 years residing in the Greater Vancouver Regional District of British Columbia | NR |
Case–control study | ||||
Suissa et al. 2002 [41] 1975 - 1997 | Saskatchewan Health DB | Assess whether regular use of ICS prevents asthma hospitalizations | Source cohort: subjects aged 5–44 years receiving ≥3 prescriptions of an antiasthma medication in any 1-year period Full cohort: all subjects with ≥1 year follow-up, irrespective of whether they were admitted to hospital for asthma during the baseline year | Primary discharge diagnosis of asthma (ICD-9 codes 493.0, 493.1, or 493.9) |
Health economic analysis | ||||
Seung et al. 2005 [42] 2004 | NACRS at CIHI, OCCI, MOHLTC billing | Determine the use of urgent care resources and annual costs for the uncontrolled asthmatic population in Canada | NR | ICD-9 Code 493 |