PSP: SOME ANSWERS
Lawrence I. Golbe, MD
Professor of Neurology, Rutgers Robert Wood Johnson Medical School Director of Clinical Affairs and Scientific Advisory Board Chairman, CurePSP
What is progressive supranuclear palsy( PSP)?
Of the approximately 15,000-20,000 people in the United States with progressive supranuclear palsy( PSP), few, if any, had ever heard of the disease before their diagnosis. In fact, most patients with PSP report that their family doctors knew nothing about it until a neurologist made the diagnosis. As of now, three of every four people with a diagnosis of PSP could have been diagnosed earlier, if their doctor had suspected it and performed the appropriate examination. However, it is appearing in medical journals more and more often, which will help doctors become familiar with PSP. This chapter should help patients and their families do the same.
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Why has no one heard of PSP?
PSP is rare: No one even realized it existed until 1963, when several patients were first described at a national neurology research convention and the disease was given its name. In retrospect, at least 12 cases of PSP had appeared in the medical literature between 1909 and 1962, but because of its resemblance to Parkinson’ s, it wasn’ t recognized as a distinct disease. The brain under the microscope is almost identical to that of“ post-encephalitic parkinsonism,” a common condition in the early 20th century but now nearly extinct, which also made for erroneous diagnoses during that era.
Although PSP is slightly more common than the well-known amyotrophic lateral sclerosis( called ALS, or Lou Gehrig’ s disease in the U. S. and motor neuron disease elsewhere), ALS is easier to diagnose than PSP and often affects much younger people. Each year an average of 1.1 people per 100,000 are newly diagnosed with PSP; five or six people per 100,000 are living with the disease. These figures are nearly identical wherever they have been carefully measured, which is in only three countries— the U. K., the U. S., and Japan.
What are the common types of PSP and their early symptoms?
PSP is occasionally referred to as Steele-Richardson-Olszewski syndrome, after the three physicians who first described the disease in 1963. The most common form is Richardson’ s syndrome, after Dr. J. C. Richardson, who only recently retired from a career in neurology research. About half of everyone with PSP has the Richardson’ s syndrome type. The most common first symptom, which occurs, on average, when a person is in her or his 60s, is loss of balance while walking. This may take the form of unexplained falls or of a stiffness and awkwardness in a person’ s gait that can resemble Parkinson’ s disease. Sometimes the falls are described by patients as attacks of dizziness. This often prompts the doctor to suspect an inner ear problem or hardening of the arteries supplying the brain.
The second most common form of PSP is called PSP-parkinsonism. Its early stages more closely resemble those of Parkinson’ s disease, with less emphasis on balance problems and behavior changes and more on tremor. These typically have a better early response to antiparkinson drugs than is typical for PSP. PSP-parkinsonism comprises about a quarter of all PSP.