Clinical Features of Patients With Progressive Supranuclear Palsy in an US Insurance Claims Database

Area of Science:

• Neurology
• Epidemiology
• Public Health

Background:

• Progressive supranuclear palsy (PSP) is a rare neurodegenerative movement disorder with limited epidemiological data.
• Understanding PSP epidemiology is crucial for public health planning and resource allocation.

Purpose of the Study:

• To estimate the age-adjusted prevalence of progressive supranuclear palsy (PSP) in the US.
• To describe antecedent diagnoses and clinical features in PSP patients up to five years prior to their first diagnostic code.

Main Methods:

• A nested case-control study utilized large US insurance databases (IBM MarketScan).
• Progressive supranuclear palsy (PSP) cases were identified using ICD-9/10 codes; controls were matched by demographics and enrollment.
• Prevalence was estimated for 2016, and antecedent diagnoses were analyzed within five years before the index date.

Main Results:

• The age-adjusted prevalence of diagnosed progressive supranuclear palsy (PSP) was 2.95 per 100,000 in 2016.
• Common pre-index diagnoses in PSP cases included gait abnormalities (79.3%), joint pain (54.9%), Parkinson's disease (54.6%), fatigue (49.8%), and cerebrovascular disease (45.6%).
• These symptoms were significantly more prevalent in PSP cases compared to controls.

Conclusions:

• The diagnosed prevalence of progressive supranuclear palsy (PSP) is lower than previously reported in some studies.
• Suggestive clinical features often appear years before a PSP diagnosis, highlighting a significant diagnostic delay.
• Identifying early clinical indicators could enable predictive models for earlier progressive supranuclear palsy (PSP) detection and intervention.