Less than half of patients newly diagnosed with asthma receive pulmonary function testing

Canadian asthma guidelines specify that asthma diagnoses should be based on both symptoms and pulmonary function testing. But new research done at the Institute for Clinical Evaluative Sciences (ICES) shows that less than half (42.7 per cent) of Ontarians newly diagnosed with asthma between 1996 and 2007 received pulmonary function testing to confirm their diagnosis.

“Making a proper diagnosis is the first step to ensuring that people with asthma get the care they need to stay healthy. It also ensures that those without asthma are not mistakenly told they have and are treated for the disease,” says Dr. Andrea Gershon, lead author, ICES scientist, and respirologist and scientist at Sunnybrook Health Sciences Centre.

Asthma is a common chronic respiratory condition. Pulmonary function testing has been empirically shown to improve asthma diagnosis and treatment and rule out other diseases, such as chronic obstructive pulmonary disease (COPD), that can present like asthma. Lack of testing increases the chance of misdiagnosis and missing other diseases in the population.

A retrospective cohort study of all individuals aged seven and older with newly diagnosed asthma and living in Ontario between 1996 and 2007 found that:

• Only 42.7 per cent of the 465,866 Ontarians newly diagnosed with asthma received pulmonary function testing to confirm their diagnosis.
• Younger children, the elderly and those of lower socioeconomic status were less likely to receive testing.
• Individuals who had seen a medical specialist were more likely to receive testing.

“Further study is needed to determine why more people with asthma do not receive pulmonary function testing and how we can increase use of this important test,” says Gershon.

Authors: Andrea Gershon, J. Charles Victor, Jun Guan, Shawn D. Aaron, Teresa To.

The study “Pulmonary function testing in the diagnosis of asthma: a population study” is in the May 2012 edition of Chest.

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.

FOR FURTHER INFORMATION CONTACT:

• Deborah Creatura
• Communications, ICES
• [email protected]
• (o) 416-480-4780