The longitudinal impact of depression on disability in Parkinson disease

Gregory M. Pontone, Catherine C. Bakker, Shaojie Chen, Zoltan Mari, Laura Marsh, Peter V. Rabins, James R. Williams, Susan S. Bassett

Research output: Contribution to journalArticlepeer-review

29 Scopus citations


Objective Depression in Parkinson disease (PD) is a common problem that worsens quality of life and causes disability. However, little is known about the longitudinal impact of depression on disability in PD. This study examined the association between disability and DSM-IV-TR depression status across six years. Methods Longitudinal cohort study with assessments at study entry, year two, four, and six conducted in the Morris K. Udall Parkinson Disease Research Center. Recruitment totaled 137 adult men and women with idiopathic PD in which up to six years of data on demographic, motor, and non-motor variables was collected. Movement disorder specialists used the structured interview for DSM-IV-TR depressive disorders and the Northwestern Disability Scale to assess depression and disability. A generalized linear mixed model was fitted with Northwestern Disability Scale score as the dependent variable to determine the effect of baseline depression status on disability. Results A total of 43 participants were depressed at baseline compared to 94 without depression. Depressed participants were more likely to be female, were less educated, were less likely to take dopamine agonists, and more likely to have motor fluctuations. Controlling for these variables, symptomatic depression predicted greater disability compared to both never depressed (p = 0.0133) and remitted depression (p = 0.0009). Disability associated with symptomatic depression at baseline was greater over the entire six-year period compared to participants with remitted depressive episodes or who were never depressed. Conclusions Persisting depression is associated with a long-term adverse impact on daily functioning in PD. Adequate treatment or spontaneous remission of depression improves ADL function.

Original languageEnglish (US)
Pages (from-to)458-465
Number of pages8
JournalInternational journal of geriatric psychiatry
Issue number5
StatePublished - May 1 2016


  • Parkinson disease
  • depression
  • disability
  • longitudinal
  • nonmotor

ASJC Scopus subject areas

  • Geriatrics and Gerontology
  • Psychiatry and Mental health


Dive into the research topics of 'The longitudinal impact of depression on disability in Parkinson disease'. Together they form a unique fingerprint.

Cite this