Measuring quality of life in progressive supranuclear palsy: The PSP-QoL

Introduction Progressive supranuclear palsy (PSP) is a neurodegenerative disorder causing parkinsonism, visual dysfunction, and balance impairment, as well as cognitive impairment and psychiatric complications. These problems, together with the emotional and social consequences of having a progressively disabling disease with shortened life expectancy, have an enormous impact on patients' health-related quality of life (HRQoL). PSP was first delineated as a distinct disorder, separate from Parkinson's disease, in 1962. It is sometimes referred to as Steele–Richardson–Olszewski syndrome after the scientists who originally described the condition. It is estimated that the disease has a prevalence of 6 per 100,000, similar to that of motor neuron disease, with the average age of onset being in the seventh decade. Mean survival from the onset of symptoms is approximately 6 years. To date, there has been little validation of any HR-QoL generic instruments in this patient group. In one small-scale study, some limited evidence for the appropriateness of the European Quality of Life Five Dimensions (EQ-5D) in this patient group was found, but less support was found for the 36-Item Short-Form Health Survey (SF-36), which some patients indicated did not cover areas of relevance to them. The Parkinson's Disease Questionnaire (PDQ-39) has been assessed for its suitability in this patient group, but it was found to lack some aspects of quality of life that are important to patients with PSP.