CONSTRUCTION AND EFFICACY OF A NOMOGRAM PREDICTION MODEL FOR HIGH RISK OF ACUTE PULMONARY EMBOLISM BASED ON CLINICAL AND BIOCHEMICAL INDEXES

Guixia Peng^*, Zhixu Chen, Huagen Zhang

Department of Respiratory Intensive Care, Meizhou People's Hospital, Meizhou 514031, Guangdong Province, China

Objective: To establish a nomogram model for predicting the high risk of acute pulmonary embolism (APE) based on clinical and biochemical indexes. 

Methods: 262 patients with acute exacerbation of chronic obstructive pulmonary disease in the respiratory department of our hospital from May 2017 to May 2020 were selected as the research subjects; 80 patients with acute pulmonary embolism formed the experimental group, and the remaining 182 patients formed the control group. The clinical data and laboratory examination indexes within 24 hours of admission were collected, and the risk factors of acute pulmonary embolism in patients with chronic obstructive pulmonary disease were analyzed by multivariate logistic regression analysis. The nomogram model for predicting acute pulmonary embolism in patients with chronic obstructive pulmonary disease was constructed with the RMS software package in R version 3.5.2, and an ROC curve analysis model was used to diagnose the critical value. 

Results: There were no significant differences in gender, hypertension, chronic kidney disease, or WBC level between the two groups (P>.05). The experimental group contained a significantly greater proportion of patients ≥ 65 years old, smokers, and patients with diabetes and coronary heart disease than the control group (P<.05). The levels of Hb, RDW, NLR, PLR, CRP, SCR, D-D, IMA, HMGB1, and ACA in the experimental group were significantly lower than those in the control group (P<.05). Multivariate logistic regression analysis showed that age ≥65 years old, NLR ≥3.5, CRP ≥2.2 mg/dl, D-D ≥1.3 mg/L, IMA ≥26.4 μg/L, HMGB1 ≥2.58 μg/L, and ACA ≥1.5 μg/L were independent risk factors for acute pulmonary embolism in patients with chronic obstructive pulmonary disease (P<.05). These factors were used in the model as predictors of acute pulmonary embolism. ROC curve analysis showed that the area under the curve of the nomogram model was .861 (95% CI = .718-.925). 

Conclusion: Age ≥65 years old, NLR ≥3.5, CRP ≥2.2 mg/dl, D-D ≥1.3 mg/L, IMA ≥26.4 μg/L, HMGB1 ≥2.58 μg/L, and ACA ≥1.5 μg/L are independent risk factors of acute pulmonary embolism in patients with chronic obstructive pulmonary disease.