Risk factors of FEV1/FVC decline in COPD patients

<bold>Background:</bold> Factors influencing the decline in forced expiratory volume in one second (FEV₁)/forced vital capacity (FVC) for chronic obstructive pulmonary disease (COPD) progression remain uncertain. We aimed to identify risk factors associated with rapid FEV₁/FVC decline in patients with COPD. <bold>Methods:</bold> This multi-centre observational study monitored eligible patients with symptoms, spirometric tests, and treatment patterns over 3 years. The annualized percentage change in the FEV₁/FVC ratio from baseline was computed, and rapid FEV₁/FVC decliners were defined as the quartile of patients exhibiting the highest annualized percentage decline in FEV₁/FVC. <bold>Results:</bold> Among 1,725 patients, 435 exhibited rapid FEV₁/FVC decline, with an annual change of -2.5 (interquartile range = -3.5–-2.0) %p. Rapid FEV₁/FVC decliners exhibited lower body mass index (BMI), higher smoking rates, elevated post-bronchodilator FEV₁, higher post-bronchodilator FEV₁/FVC, and a lower prevalence of STAR (STaging of Airflow obstruction by Ratio) stage IV. Rapid FEV₁/FVC decline was not linked to the annual exacerbation rate, but there was an association between symptom deterioration and FEV₁ decline. In multivariable analyses, low BMI, current smoking, increased modified Medical Research Council dyspnoea score, low post-bronchodilator FEV₁, low STAR stage, high forced mid-expiratory flow (FEF_25-75%), accelerated FEV₁ decline, and non-change to dual bronchodilator were identified as independent risk factors for rapid FEV₁/FVC decline. <bold>Conclusion:</bold> Identifying risk factors associated with rapid FEV₁/FVC decline may assist physician in managing COPD progression.