The Clinical Characteristics and Related Factors of Psychosis Associated with Parkinson’s Disease
|Course||Department of Neurology|
|Keywords||Parkinson’ s disease psychosis levodopa equivalent doses sleep disorder|
Background:Parkinson’s disease (PD) is a fairly common neurological degenerative diseases, characterized by motor dysfunction, such as resting tremor, rigidity, akinesia, and postural instability. Pathological examination shows that dopaminergic cells are lost and Lewy bodies formed in the substantia nigra and some other subcortical nuclei. With the development of research on PD, attention is now focused on the non-motor symptoms, including sweating, constipation, cognitive impairment, depression, anxiety, and psychotic symptoms. It is believed that the psychotic symptoms will remain after they appear, and that the psychotic symptoms can increase the burden on caregivers, and hospitalization and mortality rates. Thus, investigating the mechanism, related factors, and treatment of PD-associated psychosis is very important. According to the diagnostic criteria established by the US National Institute of Neurological Disorders and Stroke and the National Institute of Mental Health (NINDS/NIMH) in 2007, psychosis associated with PD (PDPsy) is composed of illusions, false sense of presence, hallucinations and delusions, which occur with a chronic and progressive course. To date, research based on this criteria is rare in China or abroad. It is necessary to study the prevalence and clinical features of PDPsy in Chinese PD patients, to simultaneously assess the degree of motor symptoms, and of cognitive, emotional, and sleep disorders, and to identify the factors related to PDPsy.Objectives:To describe the clinical features of psychosis associated with Parkinson’s disease,to assess its prevalence, and to ascertain whether it is correlated with age, sex, education, onset age of PD, duration of PD, severity of motor dysfunction, type or dose of PD medications, cognitive level, emotional symptoms, sleep disorders, or other factors.Methods:Eight-two PD patients recruited consecutively in the neurological clinic of Beijing Hospital, all of whom met the inclusion criteria for this research, made up the study group. Sixty-nine age-gender-, and education-matched healthy subjects made up the control group.The PD patients were asked if they experienced any psychotic symptoms that met the NINDS/NIMH criteria. At the same time, onset age, phenomena experienced, frequency, duration, and triggering and releasing factors, and level of insight were recorded. The Brief Psychiatric Rating Scale (BPRS) and Neuropsychiatric Inventory (NPI) were used to detect other psychotic symptoms. The control group was also interviewed and tested.Beside psychotic symptoms, for the study group, a clinical picture consisting of age at PD onset, type and dose of PD medications, and REM sleep behavior disorder (RBD) were also recorded. Unified Parkinson’s Disease Rating Scale (UPDRS, parts II and III) and Hoehn-Yahr staging were used for the evaluation of the severity of motor dysfunction, HAMD for emotional state, MoCA for cognition, and SCOPA-SLEEP for quality of sleep.Data were analyzed using SAS 9.12. Patient age, gender, and education level were compared between the study group and the control group. The t-test was used for continuous variables (age) and the chi-square test for categorical variables (gender and education level). The chi-square test was also used to compare the prevalence of psychosis between the two groups.To determine PDPsy-related factors among PD patients, the relationships between PDPsy and the clinical pictures in PD patients were assessed using univariate and multivariate analyses. In univariate analyses, the t-test was used for continuous variables and the chi-square test for categorical variables and a logistic model was used for multivariate analysis. A general linear model was used to compare age and PD duration at onset of PDPsy for different psychotic symptoms. To determine factors related to the number of psychotic symptoms, multivariate analysis was performed using a Poisson model. A p value< 0.05 was considered as significantly different.Results:The prevalence of psychosis was 36.59%(30/82) in PD patients and 2.90%(2/69) in the control group. The difference between the two groups was statistically significant.Thirty PD patients fit the NINDS/NIMH criteria for PD psychosis. Of these,18 (22.0%),12 (14.6%),24 (29.3%), and 6 (7.3%) patients experienced illusions, false sense of presence, hallucinations and delusions, respectively.The BPRS and NPI scores for PD patients with psychosis (PDP group) were higher than scores for PD patients without psychosis (PDNP group). There was a significant difference in BPRS, but not NPI, scores between the two groups.Univariate analysis showed that age, levodopa equivalent dosage, SCOPA-SLEEP scores, and prevalence of RBD were significantly higher in the PDP group than in the PDNP group. Multivariate analysis showed that comparing to age group 81-85, the risk decrease in the group 51-60, but doesn’t change significantly in the group 61-70 or 71-80; Hoehn-Yahr staging is a protective factor, while sleep disorder is a risk factor.Age and PD duration at onset of PDPsy have no significantly difference among different psychotic symptoms.The PD patients with more psychotic symptoms were older, with higher SCOPA-SLEEP scores. The differences were statistically significant.Conclusions:1. The prevalence of psychosis was 36.59% in PD patients, much higher than in healthy controls.2. The symptomatology of PDPsy has unique characteristics.3. PDPsy is correlated with older age, larger levodopa equivalent doses, higher SCOPA-SLEEP scores, and prevalence of RBD.4. A larger number of psychotic symptoms was correlated with older age and higher SCOPA-SLEEP scores.