Capturing ambulatory activity decline in Parkinson's disease

J Neurol Phys Ther. 2012 Jun;36(2):51-7. doi: 10.1097/NPT.0b013e318254ba7a.


Background and purpose: Relatively little is known about the natural evolution of physical activity-related participation restrictions associated with Parkinson's disease (PD). We examined this issue prospectively, using continuous monitoring technology to capture the free-living ambulatory activity of persons with PD engaging in life situations. We specifically sought (1) to explore natural, long-term changes in daily ambulatory activity and (2) to compare the responsiveness of ambulatory activity parameters to clinical measures of gait and disease severity.

Methods: Thirty-three persons with PD participated (Hoehn and Yahr range of 1-3). Participants wore a step activity monitor for up to 7 days at baseline and again at 1-year follow-up. Mean daily values were calculated for parameters indicative of amount, intensity, frequency, and duration of ambulatory activity. Clinical measures included the Unified Parkinson Disease Rating Scale, the 6-Minute Walk, and Maximal Gait Speed. Parametric tests for paired samples were used to investigate changes in ambulatory activity parameters and clinical measures.

Results: Participants had significant declines in the amount and intensity of daily ambulatory activity but not in its frequency and duration (P < 0.007). Declines occurred in the absence of changes in clinical measures of gait or disease severity. The greatest 1-year decline occurred in the number of daily minutes participants spent engaging in at least moderate-intensity ambulatory activity.

Conclusion: Continuous monitoring of ambulatory activity beyond mere step counts may serve as a distinct and important means of quantifying declining ambulatory behavior associated with disease progression or improved ambulatory behavior resulting from rehabilitation and medical and/or surgical interventions in persons with PD.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Activities of Daily Living*
  • Aged
  • Female
  • Follow-Up Studies
  • Gait / physiology*
  • Humans
  • Male
  • Middle Aged
  • Monitoring, Ambulatory / instrumentation
  • Monitoring, Ambulatory / methods*
  • Parkinson Disease / diagnosis*
  • Parkinson Disease / physiopathology
  • Prospective Studies
  • Psychiatric Status Rating Scales
  • Severity of Illness Index
  • Walking / physiology