Easy Trick to Distinguish PSP from PD

Tim Rittman, a clinical research fellow in neurology in the UK, recently posted to The PSP Association’s blog about his recent paper on using cognitive testing to differentiate Parkinson’s Disease (PD) and progressive supranuclear palsy (PSP).  Here’s a link to his blog post:


The full post is copied below.



Tim Rittman
Post to The PSP Association’s Blog

I’m pleased the JNNP have published my paper on cognitive testing in Parkinson’s disease (PD) and two rarer but important diseases that can be confused, Progressive Supranuclear Palsy (PSP) and Corticobasal Degeneration (CBD), though a little surprised no one had done the study before now. The headlines are:

  • a short test of verbal fluency distinguishes extremely well between Parkinson’s disease and Progressive Supranuclear Palsy
  • it’s not so useful for distinguishing Parkinson’s disease from Corticobasal Degeneration, or between Progressive Supranuclear Palsy and Corticobasal Degeneration
  • the ACE-R test changes over time in Parkinson’s and Corticobasal Degeneration, but not so much in Progressive Supranuclear Palsy

If you want more details, either read the paper or get in touch! Even though it’s not the main chunk of my thesis, I enjoyed writing this paper. It gets to the heart of a challenging clinical problem (and deals with the fun part of being a neurologist!), that of making the correct diagnosis in similar diseases. It uses relatively simple tools, in the Revised Addenbrooke’s Cognitive Examination and verbal fluency scores, so should apply to most clinic or hospital situations.

Parkinson’s can be a tough disease to deal with, but usually responds well to treatment for many years. Giving a diagnosis of PSP or CBD has much great implications for patients and relatives in terms of the lack or treatment response, shorter prognosis, and challenging cognitive and motor symptoms.

To those who know PSP and CBD well, there is nothing particularly surprising in our results, although the high significance levels and good performance of the tests will hopefully give some confidence in existing knowledge. My hope is this will raise awareness among those less familiar with the disorders, and enable earlier recognition of PSP and CBD. JNNP has a wide readership among clinicians, so I’m really pleased they’ve published it. I may be optimistic, but if anyone finds the paper useful because they’re struggling with differential diagnosis, then I’d love to hear from you!