Progressive Supranuclear Palsy Health Article

Definition

Progressive supranuclear palsy (PSP) is a rare degenerative disorder that causes serious and permanent deficits in movement and cognitive function.

Description

Progressive supranuclear palsy is also known as Steele-Richardson-Olszewski syndrome, reflecting the names of persons who discovered the syndrome. PSP is a neurodegenerative disease (symptoms worsen with time) first described as a distinct disorder in 1964. Characteristics of PSP include slow movement and stiffness, which are also seen similarly in Parkinson's Disease (PD). Persons affected by PSP tend to have more postural imbalance with falls than patients with PD. Additionally tremor is usually absent in PSP patients, while those with PD have tremor. PSP is an uncommon disorder and initially it may be difficult to clinically distinguish between PSP and PD. PSP usually begins to produce symptoms in the sixth decade (50–59 years of age) of life and the disorder progressively worsens more quickly than PD. Patients with PSP typically become disabled within five to ten years after diagnosis (PD has a slower progression and typically persons can become disabled 20 years after onset). PSP is the most common Parkinson-like or Parkinson-plus disease.

Demographics

The estimated prevalence (number of existing cases) among persons older than 55 years is approximately seven per 100,000 persons. Studies indicate that there may be a slightly higher male prevalence (1.53), than female prevalence (1.23) per 100,000. In Perth, Australia, the incidence (number of new cases) is estimated at three to four per million cases. The incidence rate for ages 50-99 is 5.3 per 100,000. The peak incidence (the peak age range for new cases) is in the early sixties. PSP is not thought to be genetically transmitted in families, but there are some reported cases of inherited transmission. Survey research (using a questionnaire) in 1996 revealed that patients with PSP were less likely than controls to have completed 12 years of education, which suggests that education level is a marker for direct risk factors which can include chemical exposure or nutritional problems. In 1999 a high prevalence of PSP was found in Guadeloupe (French West Indies) which is related to ingestion of certain teas that are forms of custard apple (called "soursop" and "sweetsop").