Here's the latest one from the PREDICT-PD team... this shows that intermediate markers (smell loss, subjective RBD and slowed finger tapping) persist in the higher risk group over three years of follow-up... but most interestingly higher baseline risk scores are associated with new diagnoses of PD at three years of follow-up. This is the strongest indicator yet that the PREDICT-PD algorithm is working...
Mov Disord. 2017 Jan 16. doi: 10.1002/mds.26898. [Epub ahead of print]
Noyce AJ, R'Bibo L, Peress L, Bestwick JP, Adams-Carr KL, Mencacci NE, Hawkes CH, Masters JM, Wood N, Hardy J, Giovannoni G, Lees AJ, Schrag A.
http://onlinelibrary.wiley.com/doi/10.1002/mds.26898/abstract
BACKGROUND:
A number of early features can precede the diagnosis of Parkinson's disease (PD).
OBJECTIVE:
To test an online, evidence-based algorithm to identify risk indicators of PD in the UK population.
METHODS:
Participants aged 60 to 80 years without PD completed an online survey and keyboard-tapping task annually over 3 years, and underwent smell tests and genotyping for glucocerebrosidase (GBA) and leucine-rich repeat kinase 2 (LRRK2) mutations. Risk scores were calculated based on the results of a systematic review of risk factors and early features of PD, and individuals were grouped into higher (above 15th centile), medium, and lower risk groups (below 85th centile). Previously defined indicators of increased risk of PD ("intermediate markers"), including smell loss, rapid eye movement-sleep behavior disorder, and finger-tapping speed, and incident PD were used as outcomes. The correlation of risk scores with intermediate markers and movement of individuals between risk groups was assessed each year and prospectively. Exploratory Cox regression analyses with incident PD as the dependent variable were performed.
RESULTS:
A total of 1323 participants were recruited at baseline and >79% completed assessments each year. Annual risk scores were correlated with intermediate markers of PD each year and baseline scores were correlated with intermediate markers during follow-up (all P values < 0.001). Incident PD diagnoses during follow-up were significantly associated with baseline risk score (hazard ratio = 4.39, P = .045). GBA variants or G2019S LRRK2 mutations were found in 47 participants, and the predictive power for incident PD was improved by the addition of genetic variants to risk scores.
CONCLUSIONS:
The online PREDICT-PD algorithm is a unique and simple method to identify indicators of PD risk.
I wonder if these predictives have been overtaken by developments in finding the origins of PD in the gut.
ReplyDeleteIn particular I wonder about the lady who showed she could smell PD on clothing and whether this has resulted in discovery of the aromatic substances concerned. That would be a simple test for the likelihood of eventual diagnosis if it could be put on a stick or some form of automated test.
The prospect of prediction by any reliable means allows for use of gut modifying treatments such as Parkinson's Improvement Programme prior to symptoms becoming so obvious as to lead to conventional diagnosis. Simple, safe treatments with no side effects could regress the condition at a 'pro-dromal' stage. Such treatment has been shown to regress symptoms post-diagnosis so it would be sensible to bring them forward. Maybe your next project Alastair?