Examining Ketamine Effects on Depression, Neuroplasticity, and Inflammation in Veterans With Parkinson's Disease
Parkinson's disease (PD) is a devastating illness that has a growing impact on Veterans. One of the most disabling symptoms is depression, which is common in PD and linked to poor quality of life and higher risk of suicide. Unfortunately, there is a lack of effective treatments for depression in PD. Ketamine, which has rapid and potent antidepressant effects, is a potential option but has not been tested in Veterans with PD. Studies in rodents show that ketamine may not only improve depression in PD, it may target two of the underlying drivers of the disease: (1) reduced neuroplasticity, or the brain's ability to adapt and remodel itself; and (2) elevated inflammation. The investigators are conducting a randomized, placebo-controlled study to examine if a dose of intravenous (IV) ketamine improves depression in Veterans with PD. The investigators will also examine ketamine's effects on neuroplasticity and inflammation, which will help us understand how ketamine works in PD and if it can be a useful treatment for Veterans with the disease. This study will lay groundwork for a larger clinical trial across multiple VA sites.
• Able to understand and provide written informed consent.
• Is a United States Veteran.
• Between 40-80 years old at the time of informed consent
• Have neurologist-diagnosed idiopathic Parkinson's disease (PD) for at least six months prior to enrollment
• History of inadequate response to at least one trial of antidepressant medication
• On a stable regimen of all medications for at least 2 months prior to enrollment and have no planned medication changes during the period of active participation.
• Commit to attend all in-person and remote study visits and participate in all data collection procedures.
• Have a score \>/=20 on the Montgomery-Asberg Depression Rating Scale (MADRS), consistent with moderate or greater depressive symptom severity, at Baseline.
• If already engaged in psychotherapy or other non-pharmacologic treatments for depression, agree to maintain consistent engagement throughout the period of active study participation.
⁃ If not engaged in psychotherapy or other non-pharmacologic treatments for depression, agree to avoid starting a new course of treatment for the period of active study participation.
⁃ Agree to abstain from cannabis for a minimum of 72 hours prior to assessments on Day - 1 and to remain abstinent through assessments on Day 0
⁃ If a regular user of tobacco or nicotine, agree to maintain a consistent pattern of use throughout the period of active study participation; if an infrequent/occasional user, agree to abstain throughout the period of active study participation
⁃ For people who can become pregnant or trying to conceive: agree to use highly effective contraception from entry into the trial through Day 7 assessments