A Study of the Effect of Deep Brain Stimulation on Constipation and Anosmia in Parkinson Disease


Sponsor Protocol Number: 15-005903

About this study

The purpose of this study is to investigate the effects of subthalamic nucleus and globus pallidus interna deep brain stimulation on bowel symptoms and the ability to smell things in patients with Parkinson disease and constipation.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria

  • Have Parkinson's Disease, and recruited from Deep Brain Stimulating Clinic during work-up for deep brain stimulation
  • UK Parkinson’s Disease Society Brain Bank Clinical diagnostic criteria for PD with medication-resistant motor fluctuations, dyskinesia or tremor
  • A history of symptoms of chronic constipation for 12 months
  • Symptoms of chronic constipation as defined by Rome criteria
  • Stable medication history defined as no changes in regimen for at least 3 weeks prior to the baseline period

Exclusion Criteria

  • Significant cognitive impairment, as defined by Litvan consensus criteria for PD with impairment ≥ 2 SD below the mean on two or more tests within a comprehensive neuropsychological evaluation  
  • Another likely cause for constipation (e.g. colon cancer, untreated hypothyroidism, opioids)
    • Anticholinergic medications used to treat PD will not be considered as exclusion criteria
  • Another cause for impaired olfaction (e.g. head injury, active sinusitis, active smoker)

More information


Publications are currently not available

Mayo Clinic Footer