Objective: To explore the incidence of depression in movement disorders and associated factors.
Methods: A total of 121 Parkinson's disease (PD) patients from August 2010 to June 2011 and 62 ET patients from July 2009 to June 2010 were recruited. All of them were outpatients of our hospital. PD patients received the unified Parkinson's disease rating scale (UPDRS) -motor examination and a modified Hoehn and Yahr scale to stage the severity of their disorders while 62 essential tremor (ET) patients were evaluated with tremor rating scale for tremor-motor examination (items 1 - 15 of rating scale). All participants completed Hamilton depression rating scale (24 items) to measure the presence and degree of symptoms of depression.
Results: It was found that 56.2% of PD patients and 53.2% of ET patients were depressed (HAMD score of 8 or higher). Among them, the rates of mild depression were 38.9% and 35.5%, moderate depression 15.7% and 17.7% and severe depression 1.7% and 0% in PD and ET patients respectively. No significant differences existed between each group. The factor scores of cognitive impairment were 1.81 ± 1.86 and 1.04 ± 1.07 in PD and ET patients while those of sense of despair were 2.95 ± 1.97 and 4.09 ± 2.08 in each group. The differences had statistical significance in two factor scores of two groups (P < 0.05). No differences in anxiety/somatization, lose weight, day-and-night changes, block and sleep disorders between two groups. For PD patients, the motor score of UPDRS-III was positively correlated with total HAMD score (r = 0.511, P < 0.01). Similarly, for ET patients, tremor rating scale for tremor-motor subscale score and HAMD score were positively correlated (r = 0.828, P < 0.01).
Conclusion: As two common movement disorders, PD and ET have a high incidence of depression. The severity of depression is similar in two groups. There is no significant intra-group difference in severity and frequency of depression. The most common symptoms are anxiety somatization, anhedonia, working difficulty, slowness and sleep disturbance. The depression and motor symptoms are positively correlated. Like the non-motor symptoms in PD, we should also pay attention to the non-motor symptoms in ET.