Clinical characteristics and risk factors of depression in prodromal Parkinson's disease

Depression is a highly prevalent non-motor symptom in Parkinson's disease (PD) that can manifest several years prior to the clinical diagnosis of PD. The study was aimed to investigate the clinical characteristics and related risk factors of depression in prodromal PD (pPD) subjects.

A total of 47 pPD participants from community population of East China and 39 healthy controls (HCs) were enrolled in the study. The pPD people were divided into two groups (pPD with depression and pPD without depression) according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-V) criteria. The severity of depression was assessed via the 24-item Hamilton Depression Rating Scale (HAMD-24), and the clinical features of depression were assessed by calculating seven factors of the HAMD-24. Comparisons between the two pPD subgroups were conducted to evaluate the clinical characteristics of depression in the prodromal phase of PD. Risk factors for depression in prodromal PD were analyzed by multivariate Logistic regression analysis.

The prevalence of depression in prodromal PD was 25.53%. pPD group with depression (dpPD) had significantly less years of education and higher HAMD overall scores, Hamilton Anxiety Rating Scale (HAMA) scores, PD non-motor questionnaire scores compared with pPD without depression (ndpPD). The dpPD group obtained significantly higher scores than the ndpPD group across several domains, including anxiety/somatization, cognitive impairment, day/night changes, retardation, and despair. Multivariate Logistic regression analysis showed that anxiety was an independent risk factor for depression in pPD.

Depression is common in prodromal PD and exhibit a multifaceted nature. pPD subjects with depression are vulnerable to comorbid with other non-motor symptoms. Anxiety is an established risk factor for ndPD, which indicates the critical value of early mood management in early disease intervention.