Construction And Validation Of A Risk Prediction Model For Skeletal Muscle Dysfunction In Patients With Stable Chronic Obstructive Pulmonary Disease

Objective :1.To investigate the status of skeletal muscle dysfunction(SMD)in patients with stable COPD,and to explore the risk factors affecting skeletal muscle dysfunction in patients with stable COPD.2.The risk prediction model of skeletal muscle dysfunction in patients with stable COPD was constructed to provide a basis for medical staff to develop a screening tool for skeletal muscle dysfunction in patients with stable COPD.Methods :1.Research on the evaluation content of risk factors of skeletal muscle dysfunction in patients with stable COPD :(1)Literature review,extraction and analysis of risk factors,preliminary design of risk factors of skeletal muscle dysfunction in patients with stable COPD;(2)The expert group meeting in the hospital was organized to determine the final draft of the collection table of risk factors for skeletal muscle dysfunction in patients with stable COPD.At the same time,the general data questionnaire of patients designed by the researchers was used to collect the relevant data of the patients participating in the study.2.Construction and verification of a risk prediction model for skeletal muscle dysfunction in patients with stable COPD : A total of 360 patients with stable COPD who met the inclusion and exclusion criteria in a tertiary hospital in Zhengzhou,Henan Province from December 2021 to June 2022 were selected by convenient sampling method.The data set was divided into a modeling set(n = 252)and a validation set(n = 108)by random number table method and 7 : 3 principle.The risk prediction model of skeletal muscle dysfunction in patients with stable COPD was established by using the data of the modeling set :the general data and risk factors of the patients were collected after admission,and the body composition analysis was performed before discharge to determine whether the patients had skeletal muscle dysfunction.The patients were divided into skeletal muscle dysfunction group(50 cases)and non-skeletal muscle dysfunction group(202 cases).The risk factors of skeletal muscle dysfunction in patients with stable COPD were preliminarily screened by univariate analysis.The risk factors with statistical differences in the results were included in binary logistic regression analysis to construct a risk prediction model for skeletal muscle dysfunction in patients with stable COPD.The R(R4.1.1)software package and rms package were used to draw a nomogram for visual display.Finally,the validation group(n = 108)was selected to verify the discrimination and calibration of the model.ROC curve was drawn,and the area under the ROC curve was used to evaluate the discrimination of the model.Hosmer-Lemeshow chi-square test was used,and P >0.05 was considered to be no statistically significant difference.Combined with the calibration curve,the calibration of the model was tested to verify whether there was a significant difference between the predicted results of the skeletal muscle dysfunction risk prediction model and the actual results in patients with stable COPD.Results :1.The collection table of risk factors of skeletal muscle dysfunction in patients with stable COPD :After literature review and expert group meeting,the collection table of risk factors of skeletal muscle dysfunction in patients with stable COPD was formed,which mainly includes four dimensions : social demographic data,disease related data,life behavior related data and psychological related data.2.Construction and evaluation of risk prediction model for skeletal muscle dysfunction in patients with stable COPD : A total of 360 patients with stable COPD who met the inclusion and exclusion criteria were included in this study,and their data were collected,including 252 cases in the modeling group and108 cases in the verification group.The incidence of skeletal muscle dysfunction was 19.84 %(50 cases)and 23.14 %(25 cases),respectively.In the modeling group,five predictors were included in the binary logistic regression analysis,which were closely related to skeletal muscle dysfunction in patients with stable COPD,including age(OR = 2.569),airflow obstruction(OR = 6.019),activities of daily living(OR = 7.778),depression(OR = 0.432),and nutritional status(OR = 3.093).The discrimination and consistency of the established Logistic risk prediction model were tested.The Hosmer-Lemeshow test P =0.584,the area under the ROC curve was 0.835,the Youden index was 0.558,the sensitivity was 0.765,and the specificity was 0.770.The correct rate of practical application was 78.6 %.A total of 108 patients were included in the validation group of this study.25 patients developed SMD and 83 patients did not develop SMD.The risk prediction model predicted that 18 patients developed SMD and 90 patients did not develop SMD.Compared with the actual results,the sensitivity,specificity and accuracy of the prediction model were 83.3 %,75.9 % and 78.1 %,respectively.The area under the ROC curve(AUC)of the risk prediction model of skeletal muscle dysfunction in stable COPD patients in the validation group was0.858,95 % confidence interval was [ 0.7834,0.9379 ].The results of the Hosmer-Lemeshow chi-square test showed that the test P = 0.634,the sensitivity was 0.833,and the specificity was 0.759.The total accuracy of the model was 78.1 %.The calibration curve of the model shows that the predicted value is in good agreement with the measured value.Conclusion :Stable COPD patients are prone to skeletal muscle dysfunction,especially in older COPD patients.The scores of activities of daily living scale ≤ 40,depression,nutritional assessment scale < 8,and airflow obstruction(FEV1 % pred < 50 %)were independent risk factors for skeletal muscle dysfunction in patients with stable COPD.By quantifying the risk factors of skeletal muscle dysfunction in patients with stable COPD,a risk prediction model was constructed and a nomogram was drawn.The internal validation showed that the model had good predictive efficacy and high clinical applicability for the occurrence of skeletal muscle dysfunction in patients with stable COPD.It can provide reference for medical staff to identify and accurately intervene in high-risk groups as early as possible.