Accuracy of clinical criteria for the diagnosis of progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome)

Abstract

We assessed the validity and interrater reliability of neurologists who, using four different sets of previously published criteria for the clinical diagnosis of progressive supranuclear palsy (PSP), also called Steele-Richardson-Olszewski syndrome, rated 105 autopsy-proven cases of PSP (n equals 24), Lewy body disease (n equals 29), corticobasal ganglionic degeneration (n equals 10), postencephalitic parkinsonism (n equals 7), multiple system atrophy (n equals 16), Pick9s disease (n equals 7), and other parkinsonian or dementia disorders (n equals 12). Cases were presented in random order to six neurologists. Information from each patient9s first and last visits to the medical center supplying the case was presented sequentially to the rater, and the rater9s diagnosis was compared with the neuropathologic diagnosis of each case. Interrater agreement for the diagnosis of PSP varied from substantial to near perfect, but none of the criteria had both high sensitivity and high predictive value. Because of these limitations, we used a logistic regression analysis to identify the variables from the data set that would best predict the diagnosis. This analysis identified vertical supranuclear palsy with downward gaze abnormalities and postural instability with unexplained falls as the best features for predicting the diagnosis. From the results of the regression analysis and the addition of exclusionary features, we propose optimal criteria for the clinical diagnosis of PSP. NEUROLOGY 1996;46: 922-930. TX.- In 1964, Steele, Richardson, and Olszewski described progressive supranuclear palsy (PSP), a brain neuro-degenerative disorder characterized by postural instability, parkinsonism, vertical supranuclear palsy, pseudobulbar palsy, and mild dementia. [1,2] However, the first clinical report on PSP [3,4] (also called Steele-Richardson-Olszewski syndrome) was published in 1904 and was soon followed by others. [5-7] When fully expressed, the clinical signs and symptoms of PSP are usually reliable for making the correct diagnosis, but cardinal signs, such as ophthalmoplegia, may be absent, or the only symptoms may be dementia or akinesia. [7-13] Neuropathologic examination remains the ``gold standard99 for the diagnosis of PSP. A clinical diagnosis can be mistakenly applied to pathologically determined diffuse Lewy body disease, corticobasal ganglionic degeneration (CBGD), cerebrovascular disease, Pick9s disease, or subcortical gliosis. [14-20] Conversely, neuropathologically confirmed PSP may be clinically mistaken for idiopathic Parkinson9s disease (PD), pallidonigroluysial atrophy, cerebrovascular disease, Alzheimer9s disease (AD), or CBGD. [20-26]