Clinical features of progressive supranuclear palsy in 105 Chinese patients

OBJECTIVE: To thoroughly investigate clinical characteristics of progressive supranuclear palsy (PSP) in a Chinese population. METHODS: Computer-based online searches through China National Knowledge Infrastructure and Weipu Periodical Database were performed to collect case reports of PSP published between 1980 and 2009. Clinical characteristics were analyzed. RESULTS: A total of 58 studies comprising 105 patients (76 males and 29 females) were included. All cases were sporadic and free of family history. The mean age at onset was 60.6 +/- 9.1 years, and the mean course from onset of symptoms to diagnosis was 3.4 +/- 2.4 years. The male-to-female ratio was approximately 3: 1. Onset was characterized by akinetic-rigid features and accounted for 34.3% of all cases, followed by early postural instability (25.5%), pseudobulbar palsy (9.8%), cognitive impairment (9.8%), and vertical supranuclear ophthalmoplegia (7.8%). With disease progression, vertical supranuclear ophthalmoplegia was reported in 95.1% of cases, followed by akinetic-rigid features (83.3%), pseudobulbar palsy (82.4%), axial dystonia (75.5%), cognitive impairment (72.5%), and early postural instability (69.6%). A total of 70.5% of patients exhibited abnormal electroencephalograms, and 21.4% exhibited mild abnormalities in cerebrospinal fluid. Brain CT scanning results of 37 patients showed 37.8% with midbrain and concurrent cerebral hemisphere atrophy, and 5.4% and 24.3% with midbrain and cerebral hemisphere atrophy, respectively. Brain MRI scanning results of 55 patients revealed a total of 16.4% patients with midbrain atrophy, 23.6% with midbrain and concurrent cerebral hemisphere atrophy, 32.7% with cerebral hemisphere atrophy, and 11% with brainstem atrophy. The percentage of midbrain atrophy revealed by MRI was greater than by CT. All 11 patients subjected to Mini-Mental State Examination scored < 23. A total of 10 patients underwent brain electrophysiological examination, and 80% presented with abnormalities of cerebral-evoked potential. A total of 33.3% patients presented with neurogenic damage of anal sphincter electromyography. Nine cases were neuropathologically diagnosed, and all displayed tau-positive argyrophilic globous neurofibrillary tangles, tuft-shaped astrocytes, and coiled bodies. Gene diagnosis was not performed. A total of 40 patients were misdiagnosed, including 23 (58%) as Parkinson's disease and seven (18%) as Parkinsonism; 44 patients were treated by madopar, artane, or amantadine, and only seven (16%) improved in movement. No patients exhibited improved eye movement. Of 4 patients treated with madopar and dopa agonists, 2 improved in movement. In addition, movement improved in 3 patients treated with madopar and monoamine oxidase B. CONCLUSION: PSP is a sporadic disease that often strikes middle or elderly individuals. There are no significant differences in age of onset between male and female patients, although disease progression is more rapid in female patients, likely because the time from symptom onset to disease diagnosis in females is less than in male. Akinetic-rigid features and early postural instability are the most common symptoms of onset. With disease progression, the incidence of vertical supranuclear ophthalmoplegia and akinetic-rigid features increases. MRI is a common, sensitive, and noninvasive supplemental test. However, PSP is frequently misdiagnosed as Parkinson's disease or Parkinsonism during the early stage, and anti-Parkinson treatments remain ineffective.