Development and validation of an interpretable multi-task prediction model based on heart rate variability for discriminating depression, anxiety and psychiatric comorbidities: a machine learning-driven retrospective study.

objectiveDepression and anxiety are significant global public health, their comorbidity share similar clinical symptoms with heterogeneous progression patterns for patients. The early and accurate prediction of anxiety, depression, and comorbidity of anxiety and depression is essential for timely discrimination of high-risk patients, individual treatment strategies, and hierarchical management. This study aimed to develop and validate an interpretable, multi-task prediction model using heart rate variability (HRV) for discriminating anxiety alone, depression alone, and comorbid patients with psychiatric disorders.

methodsPatients diagnosed with anxiety or depression by trained psychiatrists were retrospectively enrolled from the Department of Psychiatry, the Affiliated Hospital of Southwest Medical University, between March 2024 and April 2025. The Synthetic Minority Over-sampling Technique (SMOTE) was applied to address class imbalance, and the Recursive feature elimination (RFE) was used for feature selection. Six machine-learning algorithms, including logistic regression (LR), support vector machine (SVM), random forest (RF), extreme gradient boosting (XGBoost), k-nearest neighbor (KNN), and naïve Bayes (NB), were adopt to develop multi-task prediction models for discriminating psychiatric comorbidities. Model performances were evaluated by receiver operating characteristic (ROC) curves, accuracy, sensitivity, specificity, F1 score, and Matthews correlation coefficient (MCC). The SHapley Additive exPlanation (SHAP) method was used to visualize the feature contributions and interpret the best model.

resultsA total of 546 patients, 114 with anxiety group(20.88%), 100 with depression group (18.32%), and 332 with comorbidity of anxiety and depression (60.81%), were included in this study. The ML-based models were developed for each task using the eleven contributing features. Among the six ML models, the XGBoost achieved the best performance across all tasks. In the validation set, this model achieved the AUCs of 0.8341 (95% confidence interval [CI]:0.761–0.907) for the task of anxiety versus comorbidity of anxiety and depression, and 0.8458(95% CI:0.775–0.917) for the task of depression versus comorbidity of anxiety and depression, respectively. The clinical utility was evaluated using Decision curve analysis (DCA) and calibration curves.

conclusionThe proposed model has potential clinical application prospects and may assist clinicians to improve the accuracy and efficiency of diagnosis, and thereby facilitating timely appropriate intervention measures for patients with psychiatric disorders. CLINICAL TRIAL NUMBER: Not applicable.