Objectives-Disturbances of cognition and emotion are common in patients wit
h Parkinson's disease. Most previous studies of psychopathology in Parkinso
n's disease have focused on a single psychiatric diagnosis or condition. Th
e objective of this study was to describe the range of neuropsychiatric sym
ptoms in a representative sample of patients with Parkinson's disease.
Methods-The sample of 139 patients was drawn from an epidemiological study
of Parkinson's disease in Rogaland county, Norway, and represented 93% of t
hose who had survived during the 4 years since the initial assessment. The
diagnosis of Parkinson's disease was based on published criteria. Neuropsyc
hiatric symptoms were assessed using the neuropsychiatric inventory, a care
giver based structured interview, which assesses severity and frequency of
10 psychiatric symptoms present during the past month.
Results-At least one psychiatric symptom was reported in 61% of the sample.
The most common behaviours were depression (38%) and hallucinations (27%),
and the least common symptoms were euphoria and disinhibition. The highest
mean scores were found for depression, apathy, and hallucinations. Factor
analysis showed that hallucinations, delusions, and irritability clustered
into one factor, and apathy and anxiety constituted another factor. Psychia
tric symptoms were more common among patients living in nursing homes compa
red with home dwelling patients, and correlated with stage of disease and c
ognitive impairment, but not with age or duration of disease. No relation t
o left or right sided parkinsonism was found.
Conclusion-This study emphasises the importance of psychiatric symptoms in
Parkinson's disease, which were present in most patients. Clinicians should
focus on the emotional and cognitive disturbances in addition to the motor
manifestations of the disease.