Background: The most accurate knowledge about progressive supranuclear palsy (PSP) comes from small sample studies that preclude precise estimation of the proportion of PSP patients affected with various symptoms and the examination of factors predicting survival time.
Objective: To describe the course of PSP in a large clinically diagnosed sample of PSP patients and to identify factors predicting survival time.
Methods: We surveyed the caregivers of 318 living and 119 deceased patients with progressive supranuclear palsy. The main outcome measures were a principal symptom severity questionnaire and a signs and symptoms questionnaire.
Results: The estimated age of PSP symptom onset depends critically on how symptom onset is defined, with estimates differing by as much as 1.5 years. Men and women were represented equally (51.6% versus 48.4%) in the living sample, but men formed 61.8% of the deceased sample. Men were diagnosed later than women following symptom onset (33.4 versus 24.1 months) and died earlier following the diagnosis (37.0 versus 47.6 months). Motor and visual symptoms appeared first, followed by emotional and personality problems, cognitive impairment, and sleep changes. Whereas motor symptoms eventually affected almost every patient, emotional/personality and cognitive symptoms did not. The early onset, presence of falls, slowness, and inability to move eyes downward early in the development of the disease predicted survival time.
Conclusion: PSP is a rapidly progressive disease dominated by motor symptoms, and it affects men more frequently than women.