Abstract Introduction Based on our multicenter cluster randomized controlled trial, the Quality Improvement Program (QIP, NCT05638646), we found that quality standard (QS) implementation can significantly delay composite clinically important deterioration (CID) in high-risk chronic obstructive pulmonary disease (COPD) patients. However, the impacts of COPD Assessment Test (CAT) score and GOLD grade on this association remain unclear. Methods The analysis included data from 989 COPD patients with frequent exacerbations in the QIP study (from April 2023 to June 2025), who were recruited from 40 hospitals across five regions (east, north, west, south, and central) in China. The primary outcome was time to CID, which was defined as any of trough FEV1 decline ≥ 100 mL, CAT score increasing ≥ 2, and one moderate/severe exacerbation. Patients were stratified into the following groups: GOLD grade 1-2 and GOLD grade 3-4, or CAT 20 and CAT ≥20. Multivariable Cox regression model was used to evaluate the association between QS implementation and incident CID. Results According to baseline post-bronchodilator spirometry, 549 (56.8%) patients were categorized as GOLD grade 1-2 and 417 (43.2%) as GOLD grade 3-4. In patients with GOLD grade 1-2, QS implementation prolonged the median time to CID by 9.6 weeks (median: 26.3 weeks, 95% CI: 23.6-37.1 in QS group vs. median: 16.7 weeks, 95% CI: 13.9-23.4 in control group; P = 0.01) and reduced the 48-week CID risk by 43% (HR: 0.57, 95% CI: 0.42-0.78; P 0.01). This benefit was attenuated in the patients with GOLD grade 3-4. Here, the QS group showed a non-significant trend toward longer median time to CID (median: 25.1 weeks, 95% CI: 23.6-36.9 in QS group vs. median: 23.6 weeks 96% CI: 16.7-24.4 in control group; P = 0.06), and the associated risk reduction was smaller (HR: 0.67, 95% CI: 0.47-0.96; P = 0.03). Based on baseline CAT score, 696 (70.4%) patients were categorized as CAT 20 and 293 (29.6%) as CAT ≥20. QS implementation reduced the 48-week CID risk by 41% (HR: 0.59, 95% CI: 0.43-0.81; P 0.01) in the CAT 20 group, and 36% (HR: 0.64, 95% CI: 0.46-0.89; P 0.01) in the CAT ≥20 group. Conclusions The benefits of QS in delaying CID and reducing its risk were more pronounced among patients with lower CAT scores and earlier GOLD grades. These findings highlight the values of guideline-directed management and therapy in early-stage COPD. This abstract is funded by: AstraZeneca China
Dandan et al. (Fri,) studied this question.