Investigating dopamine's role in depression among older adults

Dopaminergic Dysfunction in Late-Life Depression

Phase 2 Interventional Vanderbilt University Medical Center · NCT04469959

This study is testing whether giving L-Dopa can improve thinking and movement in older adults with depression by looking at how dopamine works in their brains.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment100 (estimated)
Ages60 Years and up
SexAll
SponsorVanderbilt University Medical Center Academic / other
Locations2 sites (Pittsburgh, Pennsylvania and 1 other locations)
Trial IDNCT04469959 on ClinicalTrials.gov

What this trial studies

This study examines the relationship between dopaminergic dysfunction and late-life depression (LLD) in older adults. It aims to understand how aging and inflammation affect dopamine signaling, which may contribute to cognitive decline and mobility issues. The study will enroll 100 elderly participants with LLD and 70 never-depressed elders to assess dopamine-dependent behaviors using advanced imaging techniques and neuropsychological evaluations. Participants will receive either L-Dopa or a placebo to evaluate the impact on their cognitive and motor functions.

Who should consider this trial

Good fit: Ideal candidates are elderly individuals aged 60 and above with a diagnosis of major depressive disorder and evidence of dopaminergic dysfunction.

Not a fit: Patients with primary neurological disorders or other significant psychiatric conditions may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to new treatment strategies that improve cognitive and motor functions in older adults suffering from depression.

How similar studies have performed: While this approach is novel in its comprehensive examination of dopamine's role in LLD, similar studies have shown promise in understanding the neurobiological underpinnings of depression.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Age ≥ 60 years
2. Diagnostic and Statistical Manual-5 (DSM5) diagnosis of Major Depressive Disorder, Persistent Depressive Disorder, or Depression Not Otherwise Specified (NOS)
3. MADRS score ≥ 15
4. Decreased processing speed (0.5 SD below age-adjusted norms on the WAIS-IV Coding task or Trail Making Test, Part A) or decreased motor speed (gait speed/average walking speed on 15' course ≤ 1m/s, or 0.5 SD below age-, gender- and education-adjusted norms on the grooved pegboard test)
5. Capable of providing informed consent and adhering to study procedures

Exclusion Criteria:

1. Diagnosis of substance abuse or dependence (excluding Tobacco Use Disorder) in the past 12 months
2. Other psychiatric disorders including a history of psychosis, psychotic disorder, mania, or bipolar disorder. Other comorbid psychiatric disorders are allowable if the depressive disorder diagnosis is considered to be the primary problem
3. Primary neurological disorder, including dementia, stroke, Parkinson's disease, epilepsy, etc
4. SBT \> 10
5. MADRS suicide item \> 4 or other indication of acute suicidality
6. History of inpatient psychiatric hospitalization in the last year;
7. History of suicidal ideation in the last 6 months, operationalized as a 'yes' response to item 4 or 5 in the "Suicidal Ideation" section of the Columbia-Suicide Severity Rating Scale (CSSRS)
8. Any suicidal behavior in the last year (operationalized as a 'yes' response to any item in the "Suicidal Behavior" section of the CSSRS, including actual interrupted, aborted, or preparatory acts)
9. Current or recent (within the past 2 weeks) treatment with antipsychotics or mood stabilizers, or use of antidepressants where washout is not advisable
10. History of hypersensitivity, allergy, or intolerance to Carbidopa/levodopa
11. Any physical or intellectual disability adversely affecting ability to complete assessments
12. Unstable medical illness
13. Mobility limiting osteoarthritis of any lower extremity joints, symptomatic lumbar spine disease, or history of joint replacement / spine surgery that limits mobility
14. Diagnosis of HIV
15. History of significant radioactivity exposure (nuclear medicine studies or occupational exposure).

Where this trial is running

Pittsburgh, Pennsylvania and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Late Life DepressionCognitive DeclineDepressive Disorder, Treatment-ResistantLevodopaGait ImpairmentAntiparkinson agentElderlyDepressive Disorder, major
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.