Objective Confirmation of Asthma Diagnosis Often Missing in Primary Care, Study Suggests

The estimated prevalence of suspected or confirmed asthma based on electronic health record (EHR) data in a Canadian primary care practice was nearly 10%. For the majority (75%) of cases, however, no objective confirmation of the diagnosis was recorded, according to findings of a study presented at ATS 2022, the annual meeting of the American Thoracic Society, May 13-18, 2022, in San Francisco, CA.

Concern prompting the current study, investigators write, is that limited use of objective measures to confirm clinical suspicions of asthma may contribute to both misdiagnosis of the disease and suboptimal care. The purpose of this research, they note, was to collect data in a primary care practice setting that will support development of a primary care sentinel surveillance, benchmarking, and quality improvement (QI) system for asthma.

A clinical chart abstractor randomly selected and conducted a manual audit of 776 patient charts of adults aged ≥18 years with a visit within the last 5 years from the Queen's Family Health Team EHR in Kingston, Ontario, Canada. By consensus, the lead investigators selected 96 data points relevant to asthma diagnosis and management which the abstractor used to classify charts into 1 of 3 categories:

• Not asthma
• Suspected asthma: a compatible clinical history without pulmonary function tests (PFTs) consistent with asthma or a specialist diagnosis.
• Confirmed asthma: a compatible clinical history plus PFTs confirming asthma, or a specialist diagnosis.

To achieve consensus on the category assignments made by the chart abstractor, a family physician and a respirologist then reviewed all charts designated as suspected or confirmed asthma.

After excluding 33 charts deemed as patients inactive in the practice or without a visit within 5 years, 743 charts were evaluated. Mean age of patients included was 50.3 years and 56% were women.

Of the 743 charts, 83 (11.2%) mentioned asthma in a diagnosis. Of those, according to the study abstract, 11 (1.5%) were classified as not asthma, 54 (7.3%) as suspected asthma, and 18 (2.4%) as confirmed asthma.

Of the 83 charts that mentioned asthma in a diagnosis, 35 (42%) had no documentation of a method used to confirm a diagnosis of asthma. Of the 54 charts classified as suspected asthma, at least one objective measure was documented in 25 (43%) of them but the results recorded were not diagnostic of asthma.

In the absence of objective confirmation of an asthma diagnosis, either because tests were not performed or results not documented, 75% of cases in a primary care practice identified as suspected or confirmed asthma were deemed suspected.

The authors emphasize in their conclusion that diagnostic accuracy and patient outcomes could be improved by incorporating elements and algorithms into EHRs that identify suspected but unconfirmed asthma, prompting additional assessment. Surveillance systems designed for benchmarking and QI, they add, should be designed to make that differentiation.

Reference: Moloney M, Barber D, Morra A, et al. Determining the prevalence of asthma in a primary care EMR: suspected or confirmed? Am J Resp Crit Care Med. 2022;205.