Construction And Validation Of A Prediction Model For Cognitive Frailty In Elderly Patients With Chronic Obstructive Pulmonary Disease

Objective:1.To investigate the status and risk factors of cognitive frailty in elderly patients with Chronic Obstructive Pulmonary Disease（COPD）.2.To develop and verify a prediction model for predict the risk of cognitive frailty in elderly patients with COPD,and to provide reference for clinic to predict the risk of cognitive frailty in elderly COPD patients and take effective nursing care.Methods:A total of 386 elderly patients with COPD hospitalized in the respiratory department and geriatric department of a tertiary hospital in Shanxi Province from May 2020 to March2021 were selected as the traning set subjects by convenience sampling method.The investigation was performed by general information questionnaire,Frailty Phenotype（FP）,Montreal Cognitive Assessment（Mo CA）,Clinical Dementia Rating（CDR）,Short From Mini Nutritional Assessment（MNA-SF）,and Geriatric Depression Scale-15（GDS-15）.Univariate analysis and multivariate Logistic regression were used to analyze the independent risk factors of cognitive frailty in elderly COPD patients.A risk prediction model was established according to the weight of influencing factors,and nomogram was drawn by R software.From April to July 2021,158 elderly COPD patients from the same hospital were recruited for external validation.The ROC curve,calibration curve and Hosmer-Lemeshow test were used to validate the prediction performance and accuracy of the risk prediction model by bootstrap internal verification and external verification.Results:1.The morbidity of cognitive frailty in the training set was 31.9%（123/386）,the morbidity of cognitive frailty in the validation set was 35.4%（56/158）.2.The results of univariate analysis showed that there were statistically significant difference in age,smoking status,whether or not daily intellectual activity,frequency of physical exercise,whether or not comorbidity,duration of disease,GOLD,Pa O₂and Pa CO₂（P<0.05）.3.The multivariate Logistic regression analysis showed that age≥70,non-daily intellectual activity,comorbidity,duration of disease≥5 years,GOLD>Ⅰand Pa CO₂>50mm Hg（1 mm Hg=0.133 k Pa）were independent risk factors of cognitive frailty in elderly COPD patients.4.The prediction model for cognitive frailty in elderly patients with COPD w as constructed,and nomogram was drawn.5.The H-L test P=0.328,the AUC was 0.813,the sensitivity,specificity and accuracy of model prediction were 0.764,0.703 and 0.723 respectively.The Youden index was 0.481,the corresponding truncation value was 0.253,with the sensitivity of 0.846,the specificity of 0.635,and the prediction accuracy was 0.702.While the external validation H-L test P=0.468,the AUC was 0.886 with the sensitivity of 0.732 and the specificity of0.824.Calibration curves show that the calibration curves fit well with ideal curves in both sets.Conclusion:1.The prevalence of cognitive frailty in elderly COPD patients is high.2.Age≥70,non-daily intellectual activity,comorbidity,duration of disease≥5 years,GOLD>Ⅰand Pa CO₂>50 mm Hg（1 mm Hg=0.133 k Pa）can increase the risk of cognitive frailty in elderly COPD patients.3.This risk prediction model has good predictive efficiency,which can provide reference for clinic to predict the risk of cognitive frailty in elderly COPD patients and take effective nursing care.