Clinical prognostic factors in progressive supranuclear palsy: Implications for clinical trials.

Background: Progressive supranuclear palsy (PSP) is a rare neurodegenerative disease with diverse clinical phenotypes, prompting the development of new diagnostic criteria known as the MDS-PSP classification. However, little is known about the prognostic value of this classification in order to better stratify patients for the clinical trials.

Objective: To assess the impact of the different clinical phenotypes according to the MDS-PSP classification on prognosis using the clinical milestones of death, severe dysphagia, institutionalization, and need for walking aid.

Methods: A prospective cohort of 205 PSP patients from Lille University Hospital was analyzed retrospectively. Patients were classified into different MSD-PSP phenotypes according to their clinical presentation after 3 years of follow-up. The milestones of death, severe dysphagia, institutionalization, and need for walking aid were recorded, and a survival analysis was performed to describe the prognosis of each disease presentation.

Results: Median survival time was 6.4 (interquartile range (IQR): 4.8-8.6) years and mean diagnostic delay from symptom onset was 38.1 ± 22.5 months. PSP Richardson Syndrome (PSP-RS) had a poorer survival rate and a higher occurrence of severe dysphagia and need for walking aid compared to PSP variants such as PSP Parkinsonism (PSP-P), PSP postural instability without ocular motor dysfunction (PSP-PI), and other rare phenotypes.

Conclusions: PSP-RS has a less favorable prognosis compared to PSP variants stratified according to the MDS-PSP classification. This classification could assist in selecting patients for clinical trials and help design outcomes that account for the disease heterogeneity.