Our study is the first RCT to test the efficacy of the complementary use of TCC versus HE as an adjunct to standard antidepressant medication treatment of geriatric depression. We report greater improvements in depression, health-related quality of life, and memory, as well as decreases in the inflammatory marker, CRP, in older depressed participants receiving escitalopram with TCC compared with those receiving escitalopram and HE. Furthermore, by using a TCC intervention that is easily translatable to the community, the number of benefits from a simple adjunct intervention goes beyond the known benefits of standard antidepressant treatment or adjunctive pharmacologic treatment. However, this study needs to be replicated in a larger, comprehensive study, with consideration of other nonpharmacologic mind–body approaches (i.e., yoga and meditation) in this difficult-to-manage population.
Although there are no comparable studies using Tai Chi as complementary intervention added to the standard antidepressant treatment, a recent review of 36 clinical trials of Tai Chi in older adults with 3,799 participants55
reported significant improvement in physical function, balance, and depression and anxiety. Another review compared 12 RCTs of mindful exercises versus nonmindful exercises,56
indicating that both the mindful and nonmindful physical exercises were effective in their short-term effect in reducing depression levels or depressive symptoms. However, most of the studies had methodologic problems that included small sample size. Whereas Cho13
reported improvement in depression in a small sample of community-dwelling older patients who were randomly assigned to a 3-month Tai Chi intervention with 36 sessions and compared to the wait-list control after adjusting for age, gender, and education,13
social support might be partly responsible for the effect of Tai Chi on depressive symptoms. There is additional literature that Tai Chi may benefit various comorbid medical conditions of aging such as rheumatoid arthritis57
and heart failure58
and improve physical functioning and quality of life, as well as mood and anxiety and sleep quality, in healthy older adults.28,59–63
Several pathways may mediate the effects of TCC on immunity and health functioning. Research interest has focused on two components, relaxation and exercise, without necessarily considering their effects in concert, as they occur during the practice of TCC. In a meta-analysis on the effects of relaxation training, Hyman et al.64
found that various relaxation response-based interventions led to a reduction of clinical somatic symptoms, with additional effects on symptoms of anxiety and depression,65
and recovery from immune-mediated diseases.67
Prior research by our group and others have found that the administration of TCC decreases sympathetic output, improves viral-specific immunity and vaccine response, improves sleep quality, and augments overall health functioning in healthy older adults.60,68
In the current study, we found significant differences in the change in the levels of CRP over time, favoring the TCC group over HE group that supports our prior findings of beneficial influence of TCC on inflammatory markers.
The limitations of our study include a relatively small sample size, brief follow-up, and the pilot exploratory evaluation of cognitive measures. In addition, the control group of antidepressant + HE turned into a very powerful intervention that helped to relieve social isolation in older depressed participants and resulted in the significant reduction in depression severity. In the future studies, Usual Care control group can prove to be a less-active intervention. Furthermore, our participants had moderate to major depression, which raises the possibility that these findings might not generalize to a more severely depressed and/or disabled population of older adults. Finally, the cognitive test battery was relatively brief, and we did not have a nondepressed control group to determine whether improvements in cognitive function occurred as a result of TCC or improvements in depression severity. Nevertheless, the results of the study are intriguing and indicate similar benefits of Tai Chi described in other studies of older adults. This relatively simple mind–body exercise can provide substantial additional benefits not only for depression but also for physical functioning, resilience, quality of life, and cognition. Very few interventions in late-life depression manage to improve cognitive functioning in older depressed individuals.12,69
These findings should inform clinical practices and encourage clinicians to consider recommending a mind–body exercise, such as TCC, as an adjunct to the standard antidepressant treatment to improve clinical outcomes of geriatric depression. Future studies should include longer follow-up and control groups that would utilize different components (e.g., exercise and meditation) to understand the behavioral mechanisms that contribute to the benefit of TCC on depression, health functioning, cognitive performance, and inflammation in depressed older adults.