Modified and simplified clinically important deterioration: multidimensional indices of short-term disease trajectory to predict future exacerbations in patients with chronic obstructive pulmonary disease.

BACKGROUND AND AIMS: Various prediction indices based on the single time point observation have been proposed in chronic obstructive pulmonary disease (COPD), but little was known about disease trajectory as a predictor of future exacerbations. Our study explored the association between disease trajectory and future exacerbations, and validated the predictive value of the modified and simplified short-term clinically important deterioration (CID). METHODS: This study was a multicenter, prospective observational study. Patients with COPD were recruited into our study and followed up for 18 months. The modified CID (CID-C) was defined as a decrease of 100 mL in forced expiratory volume in 1 second (FEV1), or suffering exacerbations, or increase of 2 units in COPD Assessment Test (CAT) during the first 6 months follow-up. Simplified CID was defined when excluding CAT from the CID-C model. RESULTS: A total of 127 patients were enrolled in our final analysis. Compared with patients without exacerbations during the period of the 6th to the 18th month, patients with exacerbations were more likely to have frequent short-term exacerbations in the first 6 months (2.14 versus 0.21, p < 0.001). The short-term exacerbations were the best predictor for future exacerbations [odds ratio (OR): 13.25; 95% confidence interval: 5.62-34.67; p < 0.001], followed by the history of exacerbation before study entry, short-term changes in FEV1 and CAT. CID-C and Simplified CID were both significantly associated with exacerbations (OR: 7.14 and 9.74, both p < 0.001). The receiver operating characteristic curves showed that the Simplified CID had slightly better predictive capacity for future exacerbation than CID-C (0.754 versus 0.695, p = 0.02). CONCLUSION: Disease trajectory, including both the CID-C and the Simplified CID had significant predictive value for future exacerbations.The reviews of this paper are available via the supplemental material section.

Characteristics of Patients with Chronic Obstructive Pulmonary Disease Exposed to Different Environmental Risk Factors: A Large Cross-Sectional Study.

Purpose: Tobacco smoking, biomass smoke, and occupational exposure are the main risk factors for chronic obstructive pulmonary disease (COPD). The present study analyzes data on exposure to these factors in a cohort of patients with COPD and assesses their differences in demographic and clinical characteristics. Patients and Methods: The cross-sectional observational study was conducted from November 2016 to December 2019. Inclusion criteria were patients aged over 40 years old with post-bronchodilator forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) <0.7. At baseline, demographic features and exposure history were recorded. Moreover, respiratory symptoms were assessed by the COPD Assessment Test (CAT) and modified Medical Research Council scale (mMRC). A generalized linear mixed model was used to adjust for potential confounders. Results: A total of 5183 patients with COPD were included in the final analysis. The results demonstrate that exposure to tobacco combined with other risk factors resulted in significantly higher CAT scores (16.0 ± 6.7 vs 15.3 ± 6.3, P = 0.003) and more severe dyspnea (patients with mMRC ≥ 2, 71.5% vs 61.6%, P < 0.001) than exposure to tobacco alone. In addition, COPD patients with biomass smoke exposure alone had higher CAT scores than patients with only tobacco or occupational exposure (17.5 ± 6.3 vs 15.3 ± 6.3, and 15.2 ± 6.3, respectively, P < 0.05 for each comparison) and were more likely to be female and older. In addition, COPD patients who suffered from occupational exposure developed more severe dyspnea than those exposed to tobacco alone (70.8% vs 61.6%, P < 0.05), as did those exposed to biomass smoke alone (74.2% vs 61.6%, P < 0.05). This difference remained strong even after adjustment for potential confounders. Conclusion: There are significant demographic and clinical differences among COPD patients with tobacco smoking, biomass smoke, and occupational exposures.