Predictive Value of Verbatim Parkinson's Disease Patient-Reported Symptoms of Postural Instability and Falling

J Parkinsons Dis. 2021;11(4):1957-1964. doi: 10.3233/JPD-212636.


Background: Postural instability is an intractable sign of Parkinson's disease, associated with poor disease prognosis, fall risk, and decreased quality of life.

Objective: 1) Characterize verbatim reports of postural instability and associated symptoms (gait disorder, balance, falling, freezing, and posture), 2) compare reports with responses to three pre-specified questions from Part II of the Movement Disorder Society Unified Parkinson Disease Rating Scale (MDS-UPDRS), and 3) examine postural instability symptoms and MDS-UPDRS responses as predictors of future falls.

Methods: Fox Insight research participants reported their problems attributed to PD in their own words using the Parkinson Disease Patient Reports of Problems (PD-PROP). Natural language processing, clinical curation, and data mining techniques were applied to classify text into problem domains and clinically-curated symptoms. Baseline postural instability symptoms were mapped to MDS-UPDRS questions 2.11-2.13. T-tests and chi-square tests were used to compare postural instability reporters and non-reporters, and Cochran-Armitage trend tests were used to evaluate associations between PD-PROP and MDS-UPDRS responses; survival methods were utilized to evaluate the predictive utility of PD-PROP and MDS-UPDRS responses in time-to-fall analyses.

Results: Of participants within 10 years of PD diagnosis, 9,692 (56.0%) reported postural instability symptoms referable to gait unsteadiness, balance, falling, freezing, or posture at baseline. Postural instability symptoms were significantly associated with patient-reported measures from the MDS-UPDRS questions. Balance problems reported on PD-PROP and MDS-UPDRS 2.11-2.13 measures were predictive of future falls.

Conclusion: Verbatim-reported problems captured by the PD-PROP and categorized by natural language processing and clinical curation and MDS-UPDRS responses predicted falls. The PD-PROP output was more granular than, and as informative as, the categorical responses.

Keywords: Clinical trials; disease progression; falling; observational research; patient-reported outcomes.

MeSH terms

  • Accidental Falls* / statistics & numerical data
  • Humans
  • Parkinson Disease* / physiopathology
  • Patient Reported Outcome Measures
  • Postural Balance* / physiology
  • Predictive Value of Tests