Clinical heterogeneity in progressive supranuclear palsy: Problems of clinical diagnostic criteria of NINDS-SPSP in a retrospective study of seven Japanese autopsy cases

Progressive supranuclear palsy (PSP) is known to display variable atypical clinical features. In the absence of clinical markers to diagnose PSP, neuropathological examination is the "gold standard" for diagnosis. We retrospectively investigated clinical features in seven autopsy-confirmed cases of PSP. Only three patients (42.9%) matched the clinical diagnostic criteria of PSP proposed by the National Institute of Neurological Disorders and Stroke and the Society for PSP (NINDS-SPSP) at the time of death. In addition, only one patient (14.3%) matched these criteria at the time of the initial symptoms. Such underdiagnosis of PSP was mainly caused by heterogeneity, variety of the timing, and presence of symptoms in exclusion criteria. The present study also demonstrated that the clinical features of PSP may change dramatically according to the disease stage. Target symptoms should be selected based on time and stage to optimize patient quality of life.