Undiagnosed, Overdiagnosed COPD Common in Primary Health Care

Undiagnosed and overdiagnosed chronic obstructive pulmonary disease (COPD) are common in primary health care (PHC) settings when COPD is defined with use of postbronchodilator airflow obstruction, according to systematic review and meta-analysis findings published in BMJ Open Respiratory Research.

Investigators sought to quantify COPD underdiagnosis and overdiagnosis in PHC settings where postbronchodilator airflow obstruction was used to establish a diagnosis of COPD.

The researchers systematically searched the Medline (OVID) and Embase electronic databases through January 4, 2022, for relevant studies published in English. The search yielded 21 cross-sectional prevalence studies with 3959 cases of spirometry-defined COPD, with all studies reporting data on undiagnosed COPD, and 9 articles also providing data on COPD overdiagnosis. In addition, 5 COPD case series were found that reported on 7381 confirmed COPD cases in 10,142 patients; these provided data relating only to COPD overdiagnosis. Most of the studies (n=23) recruited adults aged at least 40 years of age, with an average mean age of 59.1 years (95% CI, 47.9-68.5; range, 46.8-72 years).

The 21 cross-sectional studies had a variable baseline prevalence of spirometry-defined COPD, and the proportion of spirometry-defined COPD undiagnosed in this population varied substantially by risk category (I² = 97.1%). In 3 adequately sized studies of individuals who smoked and showed COPD symptoms, 14% to 26% of patients had spirometry-confirmed COPD that was not documented in their health records. Moreover, this problem was greater among those who smoked and had only a clinician diagnosis of chronic bronchitis (25.6%; 95% CI, 23.2%-28.1%), such that a concurrent COPD diagnosis was not documented in a quarter of medical records.

In studies involving individuals who smoked who had spirometric evidence of COPD, regardless of symptoms, but did not have a COPD diagnosis, the pooled prevalence estimate was 16% (95% CI, 14%-18%). The investigators further found that in patients receiving inhaled therapies for obstructive lung diseases, COPD and/or fixed airflow obstruction in patients with asthma was undiagnosed in 25% of patients (95% CI, 22%-28%).

Among 8 heterogeneous cross-sectional studies of adequate sample size, 6 found that 26% to 52% of patients did not have postbronchodilator airflow obstruction on spirometry, despite a probable intent to manage COPD.

The baseline prevalence of spirometry-confirmed COPD varied between 50% and 75% in the adequately powered COPD case series. Among these patients, 25% to 50% had no evidence of airflow obstruction on postbronchodilator spirometry and would be considered overdiagnosed.

In citing study limitations, the researchers noted that excluding articles published in languages other than English at the title/abstract phase could have limited the generalizability of their findings. In addition, the studies were not directly assessed for publication bias and in all but 2 studies, the age spectrum of COPD was not considered.

“This review highlights that underdiagnosis and overdiagnosis of COPD is a complex and multifaceted problem, and the magnitude of this issue is expected to worsen given even further reductions in spirometry use post-COVID-19,” stated the investigators. “There is an underlying need for greater awareness and action by both at-risk patients and health care providers about reporting and documenting symptoms and then objectively investigating for a potential COPD diagnosis.”

Disclosure: Some of the study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

This article originally appeared on Pulmonology Advisor