A Predicted FEV1/FVC Model Based on a Simple Respiratory Questionnaire for Early Diagnosis of COPD in Shimane Cohort, Japan.

PURPOSE: Early detection of chronic obstructive pulmonary disease (COPD) remains challenging in primary care settings where spirometry is not always available. We aimed to develop a simple questionnaire-based approach to estimate the forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) ratio for COPD screening.

PATIENTS AND

METHODS

This was a single-center retrospective observational study based on the Shimane cohort. From 2008 to 2014, respiratory questionnaires and spirometry were performed during health check-ups of individuals aged ≥40 years. Among 2230 participants who underwent spirometry, 727 current or former smokers without a history of bronchial asthma were included for model development. Multiple regression analysis was used to identify questionnaire items associated with FEV1/FVC and to construct a simplified estimation model.

RESULTS

Four variables-age, smoking intensity, exertional dyspnea, and paroxysmal dyspnea-were independently associated with FEV1/FVC and were incorporated into the model. The model demonstrated modest explanatory power (R2 = 0.136), with no significant lack-of-fit (F = 1.152). Based on these variables, a simple four-item model enabled estimation of FEV1/FVC and identification of individuals at risk for airflow limitation.

CONCLUSION

We developed a simple questionnaire-based model to estimate FEV1/FVC using four easily obtainable variables. Although the model is exploratory and requires external validation, it may serve as a practical screening tool to identify individuals at risk for COPD in settings where spirometry is not readily available.