In a groundbreaking development, two recent studies suggest that intravenous (IV) ketamine may offer a new ray of hope for elderly patients suffering from treatment-resistant depression (TRD). This revelation is particularly significant given the previous unsuccessful attempts with intensive therapies and procedures in these patients.
Research on Ketamine Infusion for Geriatric Patients
Jonathan Kim, from Emory University and a key investigator in these studies, shares, “Despite undergoing intensive treatments and procedures, these patients had not experienced any improvement. Remarkably, after a 6-week regimen of ketamine infusion, we noticed no disparity in the treatment response between the treatment-resistant geriatric patients and the younger adults.”
This research is pivotal, as the effects of IV ketamine on geriatric patients had not been widely explored until now. Geriatric patients have notably higher rates of depression and TRD. Highlighting this lack of data, Hanadi Ajam Oughli, MD, from the Department of Psychiatry and Biobehavioral Sciences at UCLA’s David Geffen School of Medicine, comments, “We need more data on the use of IV ketamine in older adults suffering from treatment-resistant depression. There are valid concerns around safety and tolerability that might cause hesitation in opting for IV ketamine treatment among older adults and their clinicians.”
IV Ketamine vs. Nasal Administration: A Comparative Outlook
Ketamine has traditionally been employed as an anesthetic, blocking N-methyl-D-aspartate (NMDA) glutamate receptors. Administering an infusion of 0.5 mg/kg of ketamine over 40 minutes for TRD treatment can yield a rapid antidepressant response. The medication has shown promising results in reducing suicidality while enhancing mood and overall quality of life.
However, the approval of a nasal formulation of ketamine, esketamine, for TRD by the U.S. Food and Drug Administration in 2019 raised eyebrows. The high cost and lower bioavailability of esketamine, especially compared to IV ketamine, are subjects of ongoing debate.
In a retrospective chart review involving 91 older patients with TRD treated with IV ketamine between October 2016 and August 2022, Kim’s team saw no significant difference in depression severity between the two age groups.
Treatment Resistant Depression (TRD) and Psychological Well-Being in Geriatric Patients
A second study spearheaded by Oughli evaluated key outcomes in geriatric patients who received IV ketamine as part of an extensive open-label late-life trial on TRD. This study concluded that twice-weekly infusions maintained a more consistent antidepressant response compared to once-weekly infusions. It also revealed improvements in psychological well-being scores, sleep quality, and overall psychological well-being.
While it’s essential to consider that IV ketamine treatment may cause discomfort in some older patients, the severity of TRD and failure to respond to various other medications and strategies may encourage these patients to consider ketamine due to its demonstrated potential.
The encouraging findings from these studies require further validation through larger randomized controlled trials. The conversation around IV ketamine is vital, given the high prevalence of depression and TRD in the geriatric population. As such, additional research and rigorous clinical trials are crucial in defining guidelines for its use in this demographic.