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International Parkinson and Movement Disorder Society
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Prodromal PD Calculator

Review: Update of the MDS research criteria for prodromal Parkinson's disease

Authors: Sebastian Heinzel PhD, Daniela Berg MD, Thomas Gasser MD, Honglei Chen MD, PhD, Chun Yao MSc, Ronald B. Postuma MD, MSc, and the MDS Task Force on the Definition of Parkinson's Disease.

First published: 14 August 2019

Early View

Daniela Berg and Ronald B. Postuma contributed equally to this article.

Relevant conflicts of interest/financial disclosures: None.

Funding agencies: None.

Members of the MDS Task Force on the Definition of Parkinson's Disease: Daniela Berg, Ronald B Postuma. Cochairs: Charles H Adler, Bastiaan Bloem, Piu Chan, Günther Deuschl, Bruno Dubois, Thomas Gasser, Christopher G Goetz, Glenda M Halliday, John Hardy, Anthony E Lang, Irene Litvan, Kenneth Marek, José Obeso, Wolfgang Oertel, C Warren Olanow, Werner Poewe, and Matthew Stern.


A Web-based Medical Calculator for Prodromal Risk in Parkinsonism

Authors: Sebastian Heinzel PhD, Daniela Berg MD, Thomas M. Gasser MD, Honglei Chen MD, Chun Yao MSc, Ronald B. Postuma MD, MSc
Architectured by: Chun Yao

Read Me

This online calculator was built for the purpose of clinical and research usage only. The results should be interpreted by experienced neurologist or movement disorder specialists as a reference for diagnosis. Note that the online calculator will not save or retrieve any information from your computer. Simply scroll down each box and choose whatever is appropriate. For specific symptoms and markers you find further information and instructions when you click on the link in the symptom/marker name. The results of the risk of prodromal PD will be calculated and displayed automatically. It is important to note that the online calculator will not save or retrieve any information from your computer.

Simply scroll down each box and choose whatever is appropriate. The results will be calcualted and displayed automatically.

*If the webpage is not working, please, refressh the page or allow the plugin. Sometimes, antivirus software may block unknown webpage functioning to protect your computer.

Prior Probability: (Auto-output Field)


Risk Markers:

1. Sex:
2. Regular Pesticide Exposure: (i.e., ≥100 episodes of non-occupational exposure)
3. Occupational Solvent Exposure:
4. Consume Caffeinated Bevarage: (i.e., <3 cups of coffee/6 cups of black tea per-week)
5. Smoking:
6. Family History of PD (first degree relative)?
7-1. Intermediate Strength Genetic Variants associated with PD GBA Mutation (for specific mutation subtypes see: Anheim 2012, Neurology) LRRK2 (p.G2019S) Mutation (Lee 2017, Mov Disord)
7-2. Polygenic Risk Score:
8. Documented Substantia Nigra Hyperechogenicity on Transcranial Ultrasound (i.e., SN+ corresponds to an uni- or bilateral hyperechogenic area in the SN (>90th percentile of the reference sample))
9. Medical Diagnosis of Type II Diabetes Mellitus
10. Physical Inactivity: (i.e., <1 hour/week of physical activity causing elevating in breath and heart rate/sweating)
11. Low Plasma Urate (Men)

Prodromal Markers:

(Auto-output Field)
A. Clinical Non-motor Markers: (Auto-output Field)
A-1.1 Polysomnograph-proven RBD:
A-1.2 Are you able to exclude differential diagnosis when screening for RBD? Results of screeening for RBD: (*Differential diagnosis and possible drug-induced/nacrolepsy-related dream enactment should be excluded)
A-2 Excessive Daytime Somnolence: (* Possible drug-induced or nacrolepsy-related RBD symptom should be excluded)
A-3 Olfactory Loss: (i.e., total score below age-and-sex-adjusted threshold in a quantitative olfactory test (e.g. Sniffin' Stick, UPSIT or B-SIT)
A-4 Constipation: (i.e., constipation requiring treatment more than once a week, or spontaneous bowel movement frequency less than every other day)
A-5 Urinary Dysfunction:
A-6 Severe Erectile Dysfunction:
A-7 Has a measurement of orthostatic hypotension been performed at the clinic? Orthostatic Hypotension:
A-8 Depression (with/without Anxiety): (Clinical diagnosis or reaching thresholds of at least moderate depression in depression inventories/questionnaires)
A-9 Global Cognitive Deficit: (i.e., diagnosed with mild cognitive impairment or score more than 1.5SD below the Age-and-sex-adjusted Norm)
B. Clinical Motor Markers: (Auto-output Field)
B-1 UPDRS III Total Score >3 or MDS UPDRS III Total Score >6 (Physician Examination): (*Excluding action tremor and potential confounds, such as arthritis)
B-2 Abnormal Quantitative Motor Testing (i.e., < Mean + 1SD): (Abnormalities of quantitative motor tests according to defined thresholds, with performance 1 standard deviation (SD) below age-adjusted normal values. The motor test must be clearly demonstrably abnormal in clinical PD, with specificity compared to controls of ≥80%. If multiple quantitative motor tests are performed, the individual must score below threshold on ≥50% of them. Uncertain or borderline test results should not be included (use evaluator judgment).)
C. Clinical Biomarkers: The specific marker (and evaluation technique of this marker) has a documented specificity >80% in at least 2 studies.
C-1 Clear Abnormality on Dopaminergic Imaging: (e.g., < 65% normal, 2SD below mean)

Scores and Diagnosis

Total LR Threshold Required for Probable Prodromal PD:
Total Estimated LR:
Estimated Probability (%):
Probable Prodromal PD:
Reference: Heinzel S, Berg D, Gasser T, et al. Update of the MDS Research Criteria for Prodromal PD. Mov Disord 2019
Disclaimer and Terms of Use

All use of the features provided on the website of the International Parkinson and Movement Disorder Society (MDS) are at the sole risk of the user. Any user of the Prodromal PD Calculator, or the information gained through use of the tool, hereby disclaims and releases MDS from and against any and all liability related to such use. Any user not agreeing to the foregoing shall not use, and does not have permission to use the tool.

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