Study Links Lung Function, Education, Area of Residence as Predictors of COPD Diagnostic Delay

A patient’s lung function, education level, and area of residence were identified as predictors for diagnostic delay of chronic obstructive pulmonary disease (COPD), potentially resulting in patients receiving diagnoses after their disease has progressed to a more severe level, according to a recent analysis.

The cross-sectional study, published in Scientific Reports, is the first study to assess factors contributing to diagnostic delays in patients with COPD in China, which has a high rate of senior citizens and a COPD population of almost 100,000.

Studies have shown that early diagnosis and intervention of COPD can help prevent disease progression, improve lung function, and reduce exacerbation frequency. There are several physician-, patient-, and disease-related factors that can affect the ability to diagnose COPD early, and many patients lack knowledge and awareness about the disease.

Additionally, the China Pulmonary Health study found that only 2.6% of patients with COPD using a pulmonary function test were aware they had COPD. A study from the Republic of Korea also found that among smokers, only 23.8% knew about COPD and only 30.5% had undergone a lung function test. A Danish study also found that 28% of smokers did not think COPD was a fatal disease.

The investigators recruited 530 patients with COPD aged 35 to 80 years who visited the respiratory outpatient department of the Second Xiangya Hospital, Central South University in Changsha, China, between July 2019 and February 2020. Data were collected by having the patients complete a series of questionnaires. After exclusion, 408 patients were included in the analysis.

Among the patients, 90.2% (n = 368) were male, and the mean age was 65 (range, 58-69) years. In the year prior to the study period, 41.7% (n = 170) had not had an acute exacerbation, 27.2% (n = 111) had 1 acute exacerbation, and 31.1% (n = 127) had 2 or more acute exacerbations. There were 135 (33.1%) patients who lived in cities and 273 (66.9%) patients who lived in rural areas.

For lung function, the average forced expiratory volume in 1 second (FEV1) predicted was 53.3%. For the first visit, 16.4% of patients chose to visit a first-level hospital, 29.9% of patients chose a second-level hospital, and 53.7% chose a third-level hospital.

The median duration of diagnostic delay was 230 (range, 50-720) days. During their first visit, 47.3% (n = 193) received a pulmonary function test and 52.7% (n = 215) did not. The investigators found that as the hospital level increased, the proportion of pulmonary function tests during a patient’s first visit increased as well (first level, 1.5%, n = 1; second level, 24.6%, n = 30; third level, 74.0%, n = 162; P < .001).

“The proportion of patients whose first diagnosis institution was a high-level hospital, who underwent pulmonary function tests, was much higher than that of patients who visited primary hospitals. Therefore, the classification of hospitals is more conducive to understanding the true status of patients’ lung function. In addition, this also illustrates the importance of propagating and popularising lung function tests in primary hospitals,” wrote the investigators.

The linear regression analysis revealed that FEV1 (P < .05), resident manner (P < .001), and education level (P <.001) were significant predictors of COPD diagnostic delay, with patients who had worse lung function, lived in rural areas, and had lower levels of education being more likely to experience delays. The latter was surprising to the investigators who hypothesized that patients with milder cases would experience less symptoms burden, potentially leading them to not seek medical treatment until the disease progresses.

They said that patients who live in rural areas have poorer access to medical resources. Additionally, patients with lower education levels may have less awareness of when to seek medical care.

Several limitations were identified in the study, including that generalizability is restricted because only outpatients from a single center were examined and that the relationship between knowledge level and diagnostic delay for COPD was not analyzed. The investigators said that future studies should examine other public and private hospitals and investigate how interventions targeting these predictors impact diagnostic delays.

Reference

Dai Z, Ma Y, Zhan Z, Chen P, Chen Y. Analysis of diagnostic delay and its influencing factors in patients with chronic obstructive pulmonary disease: A cross‐sectional study. Sci Rep. July 9, 2021; 11(14):213. doi: 10.1038/s41598-021-93499-9