OBJECTIVES : Progressive Supranuclear Palsy (PSP) is a neurodegenerative movement disorder characterised by a progressive parkinsonism with early postural instability, falls, and supranuclear gaze palsy. Although acknowledged to be rare, the prevalence of PSP is not well quantified and published studies have reported outwardly heterogeneous estimates. We sought to estimate the prevalence across the EU, Japan and USA by synthesising and standardising published evidence.

METHODS : A literature review for studies that reported on the incidence, prevalence or epidemiology of PSP syndrome was performed. Prevalence ratios were estimated from the data reported in each study. Where possible, estimates were standardised to the EU, Japanese and USA populations in 2018.

RESULTS : Among the seven studies that reported the prevalence of PSP in Europe, estimates ranged from 0.02–0.83 cases per 10,000 population. Age–sex standardisation to the EU28 population yielded an adjusted estimate of 0.64 cases per 10,000, equivalent to 33,000 people living with PSP in Europe. Four Japanese studies were identified that had used standard case ascertainment methods which, when standardised to the 2018 Japanese population, yielded a prevalence of 0.7–3.0 per 10,000 population. Only two studies were identified that reported on the prevalence of clinically diagnosed PSP in the USA (0.14 and 2.95 cases per 10,000) and the results may not be generalisable to the total US population due to the data sources and methods used. Standardising estimates from Europe to the USA population yielded an estimated prevalence of 0.6 per 10,000 or around 20,000 people living with PSP in the USA in 2018.

CONCLUSIONS : Published studies demonstrate that PSP is a rare disease that meets the prevalence criteria for orphan disease designation in the EU, Japan and USA.