Four more poster presentations from the PSP/CBD conference in London in October. Keep in mind that this work has not yet been peer-reviewed by a journal. It has merely been screened by CurePSP and the PSP Association of the UK.

• “Strategy adherence” is a measure of the degree to which one is consistent in going about a complicated cognitive pen-and-paper task.  Researchers administered the measure every 3 months for a year to people with PSP or PD and also to healthy controls of similar ages.  Each visit also included two more conventional cognitive measures – the Mini Mental Status Exam and the Montreal Cognitive Assessment.  Over the year, they found — in PSP but not in PD nor controls –a very clear and progressive problem with strategy adherence, but not in the conventional tests.  This provides a statistically sensitive test by which to assess disease-slowing ability of experimental drugs for PSP. (Maksymilian Brzezicki, et al, Oxford University, UK)
• A new gene contributing modestly to the cause of PSP has been found.  It’s called C4A and is involved in the complement cascade, an important part of the immune system.  Ten other genes had been previously found to contribute similarly modest degrees of causation to PSP.  One additional gene influences PSP onset age.  Even if the effects of all 10 causative genes are totaled, most of the cause of PSP remains unexplained.  The current leading theory is that some outside influence is also necessary.  In fact, it may take multiple genes from this list plus multiple outside factors – plus a dose of randomness. (Kurt Farrell, et al, Icahn School of Medicine at Mt. Sinai, New York, NY)
• Neurofilament light chain (NfL) is a protein in spinal fluid and blood that is elevated in PSP and several other brain degenerations.  Its role as a diagnostic test for PSP remains uncertain, but it does seem to correlate well with rate of symptom progression.  In this report, patients with PSP-Richardson’s syndrome, a rapidly-progressing form of PSP, had higher NfL levels in spinal fluid but only borderline-higher levels in blood, relative to patients with more slowly progressing forms of the disease.  Furthermore, the correlation between spinal fluid and blood levels was only modest.  The conclusion is that levels of NfL in spinal fluid, but so far not in blood, could prove valuable as a prognostic test in PSP. (M. Fernandez, et al University of Barcelona, Spain)
• The PSP Rating Scale (PSPRS) is nearly universally used as the primary outcome measure in clinical treatment trials.  It progresses in a statistically reliable way over a 1-year timespan,but has been criticized for relying in large part on the neurological exam rather than mostly on patient-reported symptoms.  The PSP Quality of Life Scale (PSP-QoL), on the other hand, relies entirely on patient/caregiver-reported data but has been found in the past not to progress in a sufficiently robust fashion.  Now, researchers have directly compared the two using data from a 124-week, completed, negative drug trial. They found only a modest but still statistically significant correlation between the two, with a correlation coefficient of 0.325 (perfect correlation is 1.0) and conclude that the PSP QoL could provide an adequate outcome measure for PSP trials in the future if this result is confirmed. (Jay Iyer, et al, Harvard Medical School)