Simple, Low-cost Tests May Help Identify Undiagnosed COPD in China
Low-cost screening involving a questionnaire and a breathing test may help identify patients with undiagnosed chronic obstructive pulmonary disease (COPD), a study conducted in China has found.
Among the combinations tested, the Chinese symptom-based questionnaire (C-SBQ) combined with microspirometry — a test that measures how much air a patient can breathe out in one forced breath — provided the best way of spotting those in need of treatment for COPD.
“COPD develops slowly, resulting in delays in symptom recognition and high rates of underdiagnosis,” Peymané Adab, MD, professor at the University of Birmingham’s Institute of Applied Health Research, and one of the study authors, said in a university press release.
“Simple screening tests can help identify undiagnosed COPD within China’s primary care network — the first step in providing people with early treatment and potentially saving lives and reducing the burden on the country’s healthcare system,” Adab added.
The study, “Accuracy and cost-effectiveness of different screening strategies for identifying undiagnosed COPD among primary care patients (≥40 years) in China: a cross-sectional screening test accuracy study: findings from the Breathe Well group,” was published in the journal BMJ Open.
COPD is common but may go undiagnosed in its early stages. This means that without proper treatment, patients may see their symptoms worsen before they seek medical attention.
For this reason, early diagnosis is being made a priority in many countries, including China, where national policies recommend screening for COPD, but do not specify which screening tests to use.
To know which tests are best to identify undiagnosed COPD patients, a team of international researchers recruited people from urban and rural community health centers in four regions of China. As noted by the researchers, this strategy should help increase the extent to which study findings might be applicable to other settings.
The study included 2,445 people who were recruited from February to December 2019. The mean average age of the participants was 59.8 years, and 956 (39.1%) were men.
All completed four different questionnaires covering demographics, smoking status, medical diagnoses, respiratory symptoms, and quality of life. They also took two different tests to measure airflow obstruction: microspirometry and peak flow. Spirometry was used as a reference.
Of the 2,445 people, 88 (3.6%) had a previous diagnosis of COPD and 333 (13.6%) had spirometry-confirmed airflow obstruction.
Although “spirometry is required for clinical diagnosis, it is not widely available in primary care settings in China,” the researchers wrote. “Screening could reduce the numbers needing spirometry referral.”
Microspirometry and peak flow were more sensitive and specific at diagnosing COPD than questionnaires, the most accurate of which was C-SBQ.
The combination of C-SBQ and microspirometry increased sensitivity, with an incremental cost of 385 yuan (about $60) per additional case identified, compared with peak flow.
“Further work is needed to fully assess clinical efficiency and cost-effectiveness, but this simple combination of questionnaire and breathing test is a promising, low cost option to be used across China to provide early diagnosis of COPD,” said Rachel Jordan, PhD, at the University of Birmingham’s Institute of Applied Health Research, and also an author of the study.
Primary care doctors are often the first medical professionals to see patients with early-stage COPD. Implementing a screening test “to identify undiagnosed COPD within the primary care setting in China is possible,” the researchers wrote, adding that “a combination of C-SBQ and microspirometry is the most sensitive and cost-effective.”