Abstract: BACKGROUND: Understanding the characteristics of lung tissue repair and risk factors in patients with chronic obstructive pulmonary disease is crucial for improving disease management and enhancing patient quality of life. Existing clinical indicators cannot accurately quantify the tissue repair potential and disease progression risk in patients with a history of frequent hospitalizations.
OBJECTIVE: To conduct a risk prediction model analysis of lung tissue repair mechanisms in chronic obstructive pulmonary disease based on computer simulation and case validation, thereby promoting lung tissue repair/regeneration in patients with chronic obstructive pulmonary disease, reducing the frequency of hospitalizations, and improving the quality of life.
METHODS: Medical records from 200 patients with chronic obstructive pulmonary disease hospitalized at Beijing Jingmei Group General Hospital for from 2022-10-01 to 2023-10-01 were collected. Patients were grouped based on the number of hospitalizations for chronic obstructive pulmonary disease within 1 year after discharge: 100 patients hospitalized ≥ 2 times within 1 year were classified as the frequent hospitalization group, while 100 patients hospitalized < 2 times within 1 year were classified as the non-frequent hospitalization group. General clinical data, pulmonary function, blood gas analysis, and hematological indicators were collected and compared between the two groups. Variables with P < 0.05 were progressively incorporated into a multivariate logistic regression model to identify risk factors for re-admission within 1 year after discharge. The area under the receiver operating characteristic curve was used to evaluate the predictive performance of the clinical risk factor model for re-admission within 1 year.
RESULTS AND CONCLUSION: (1) Pulmonary function: Significant differences were observed between the two groups in the following parameters (P < 0.05): percentage of forced expiratory volume in one second relative to predicted value, forced vital capacity, percentage of forced vital capacity relative to predicted value, ratio of forced expiratory volume in one second to forced vital capacity, residual volume/total lung capacity ratio, pulmonary diffusion capacity for carbon monoxide, and carbon monoxide diffusion capacity per unit alveolar volume. (2) Blood gas analysis: Significant differences were observed between the two groups in terms of partial pressure of oxygen, partial pressure of carbon dioxide, oxygen saturation, and type of respiratory failure (P < 0.05). (3) Hematological indicators: Significant differences were observed between the two groups in terms of absolute neutrophil count, D-dimer levels, absolute lymphocyte count, neutrophil percentage, and red cell distribution width (P < 0.05). However, no significant differences were found between the two groups in terms of eosinophil percentage, fibrinogen levels, and absolute eosinophil count (P > 0.05). (4) Logistic regression analysis revealed that the percentage of forced expiratory volume in the first second relative to the predicted value [odds ratio (OR)=1.01, 95% confidence interval (CI): 1.004-1.017, P=0.011], carbon monoxide diffusion capacity (OR=2.28, 95% CI: 1.270-3.025, P=0.004), type I respiratory failure (OR=3.15, 95% CI: 2.414-5.947, P=0.001), type II respiratory failure (OR=7.03, 95% CI: 1.688-8.604, P=0.001), and red cell distribution width (OR=1.50, 95% CI: 0.65-3.44, P < 0.0001) were risk factors for frequent hospitalizations in patients with chronic obstructive pulmonary disease. (5) Analysis of the area under the receiver operating characteristic curve revealed that when the forced expiratory volume in 1 second was below 52.9% of predicted value, the risk of frequent hospitalizations increased in patients with chronic obstructive pulmonary disease. When the carbon monoxide diffusion capacity was below 4 mmol/(min·kPa), the risk of frequent hospitalizations increased in patients with chronic obstructive pulmonary disease; the risk of frequent hospitalizations increased in chronic obstructive pulmonary disease patients with type I respiratory failure. When the red cell distribution width exceeded 14.5%, the risk of frequent hospitalizations increased in patients with chronic obstructive pulmonary disease. (6) Logistic regression modeling and receiver operating characteristic curve analysis revealed that severe impairment of diffusion capacity, concomitant respiratory failure, and elevated red cell distribution width are major risk factors for frequent hospitalizations in patients with chronic obstructive pulmonary disease. Early identification and timely intervention targeting these factors are crucial for enhancing lung tissue repair potential, predicting disease progression risk, and improving quality of life in such patients.

Key words: chronic obstructive pulmonary disease, frequent hospitalization, risk factors, pulmonary function, diffusion capacity