Progressive supranuclear palsy (PSP) is art unusual neurodegenerative
disorder that superficially resembles Parkinson's disease (PD). It is
characterized by gaze palsy, bulbar signs, parkinsonian signs, and men
tal changes. While mental changes are a frequent finding, they have, w
ith the exception of dementia, been poorly defined, In this study, 19
patients with PSP were evaluated psychiatrically and compared with 42
patients with PD. Fifty-two percent of the patients had some degree of
dementia, as measured by the Mini-Mental State Exam. Eight (42%) of t
he PSP patients had other psychiatric diagnoses, mostly relatively mil
d depression or anxiety, though two patients had more severe depressio
n. Six (32%) patients had pathologic laughing or crying, and four of t
hese had a psychiatric diagnosis other than dementia. The PSP patients
did not differ from the PD patients on measures of depression or anxi
ety and did not have a greater rate of formal psychiatric diagnoses. T
his study confirms previous reports of dementia as a common feature of
PSP. It further suggests that psychiatric disturbances, while common,
are generally relatively mild, though more serious psychiatric illnes
s may be seen.