Abstract: Objective Intradialytic hypotension (IDH) is one of the most common complications in hemodialysis. The purpose of this study was to predict the risk of IDH in hemodialysis patients by constructing a nomogram model.  Methods  The hemodialysis patients in Sichuan Provincial People's Hospital from 2014 to 2020 was included in this study. Their basic information, laboratory examinations and dialysis treatment records were collected. A multivariate logistic regression model was designed, and the nomogram model was constructed using R language program to predict the risk of IDH. The receiver operating characteristic curve (ROC) and calibration curves were used to investigate and evaluate the discrimination and calibration of the model, while the decision curve analysis was used to evaluate its clinical validity.  Results  A total of 3,906 patients and 314,534 dialysis records were included. After regression analysis, age (OR=1.016, 95% CI 1.015~1.017, P＜0.001), gender (male OR=1.280, 95% CI：1.268~1.282, P＜0.001), pre-dialysis systolic blood pressure (＜90mmHg OR=7.242, 95% CI：6.376~8.156, P＜0.001;>140mmHg OR=2.656, 95% CI：2.345~2.996, P＜0.001), pre-dialysis diastolic blood pressure (＜60mmHg OR=3.772, 95% CI：3.596~3.883, P＜0.001;    ＞90mmHg OR=1.741, 95% CI：1.707~1.783, P＜0.001), heart rate (＜60/min OR=2.314, 95% CI：2.173~2.461, P＜0.001; >100/min OR=1.456, 95% CI：1.397~1.514, P＜0.001), preliminary ultrafiltration volume (OR=1.350, 95% CI：1.336~1.362, P＜0.001), hemoglobin (OR=1.001, 95% CI：1.001~1.002, P＜0.001) and blood calcium (＜2.25mmol/L OR=1.270, 95% CI：1.211~1.339, P＜0.001; ＞2.75mmol/L OR=1.087, 95% CI 1.068~1.102, P＜0.001) were identified and input into the nomogram. The nomogram shows better discrimination. The area under the receiver operating characteristic (ROC) curve of the training set is 0.729 (95% CI 0.727~0.732), and the internal verification C-index is 0.730; the area under the ROC curve of the test set is 0.727 (95% CI 0.724~0.731). The calibration curve of IDH probability shows the consistency between the predicted probability of nomogram and the actual probability.  Conclusion  The nomogram model constructed in this study can be used to identify the patients with high-risk of IDH and to help clinicians make personalized diagnosis and treatment interventions for IDH, indicating that this nomogram model may have clinical utilities.

Key words: emodialysis, Intradialytic hypotension, Nomogram