Objective：To explore the predictive value of neutrophil-to-lymphocyte ratio（NLR）and prognostic nutritional index（PNI） in predicting depression in patients with Parkinson’s disease（PD），and to construct and verify a nomogram prediction model for the risk of PD patients with depression. Methods：182 PD patients treated at the the Affiliated Huai’an No.1 People’s Hospital of Nanjing Medical University were continuously collected as the PD group. According to the hamilton depression rating scale（HAMD）-24 score， the patients with PD were divided into two groups：PD without depression group and PD with depression group. At the same time，175 healthy individuals undergoing physical examinations were selected as the healthy control group. The differences in clinical data between groups were compared，and a multivariate logistic regression analysis was used to explore the influencing factors of depression in PD patients with depression，and based on this，a personalized nomogram model for predicting the risk of depression in PD patients was constructed and validated. Results：Compared with the healthy control group，patients with PD showed lower PNI but higher NLR （P < 0.05）. Compared with PD patients without depression，PD patients with depression showed higher levels of NLR，levodopa equivalant dose（LED），Hoehn-Yahr stage，course of disease，and part Ⅲ of the unified parkinson’s disease rating scale（UPDRS-Ⅲ）； but lower level of PNI（P < 0.05）. The results of multivariate logistic regression analysis showed that NLR，LED and UPDRS-Ⅲ were independent risk factors for PD patients with depression；while PNI was an independent protective factor for PD patients with depression. Based on the results of multivariate logistic regression analysis，a individualized nomogram model was constructed to predict the risk of depression in PD patients. The area under the ROC curve（AUC）of the nomogram model was 0.835（95%CI：0.776- 0.893，P < 0.01）. The Hosmer-Lemeshow test showed χ2 =11.576（P > 0.05）. Conclusion：The individualized nomogram model based on PNI，NLR，LED and UPDRS-Ⅲ can effectively predict the risk of depression in PD patients and has certain clinical application value.
