Mindfulness-Based Cognitive Therapy Improves Anxiety and Depression in People with Parkinson's Disease: Evidence from Two Pilot Clinical Trials

Introduction Anxiety and depression are among the most common nonmotor symptoms of Parkinson's disease (PD).1,2 Mindfulness-based cognitive therapy (MBCT) is a manualized psychotherapy intervention conducted in 8-week group sessions, along with participant independent daily practice. MBCT has been shown to prevent the relapse of recurrent depression and improve anxiety and has been studied in patients with neurological diseases, including PD.3-7 Using a modified MBCT protocol, we investigated MBCT effectiveness in reducing anxiety and depression for people with PD in 2 pilot clinical trials (NCT03904654, NCT04469049). Methods People with PD and mild-to-moderate anxiety and/or depressive symptoms participated in one of 2 studies. The first study started in-person in September 2019 and concluded in March 2020 (the last 2 sessions were virtual, due to the COVID pandemic) and was limited to San Francisco Bay Area residents.8 The second study was entirely virtual, took place from November 2020 to June 2021, and was open to people with PD from across the U.S. and their caregivers.9,10 Participant demographic and clinical variables, pre- and post-intervention Generalized Anxiety Disorder-7 Item (GAD-7) and Patient Health Questionnaire-9 (PHQ-9) scores, and a participant satisfaction survey were collected. Descriptive statistics were used to summarize the demographic and clinical variables. Linear mixed-effects regression models with fixed effects for time (Pre-, Post-) and study (Study 1, Study 2) and a random effect for person-specific intercept were used to assess pre- to post - changes in GAD-7 and PHQ-9 scores. This study represents a secondary analysis of combined data from the 2 clinical trials, restricting the analysis to people with PD and more than minimal anxiety and/or depressive symptoms (GAD-7 and/or PHQ-9 scores ≥ 5, respectively). Results In total, 5 MBCT groups (2 in-person, 3 virtual) were conducted. The subsample analyzed included 15 (8 women, mean age 64.2, SD 7.4) people with PD in Study 1 and 13 (7 women, mean age 61.6, SD 6.4) in Study 2. One participant withdrew. At baseline, 25 participants had anxiety symptoms (GAD-7 score mean 7.9, SD 2.9) and 22 had depressive symptoms (PHQ-9 score mean 9.8, SD 3.4). There were significant reductions in both anxiety and depression measures at the conclusion of the MBCT intervention. Post- to pre- estimated difference (95% confidence interval) was -2.1 (-3.9 to -0.4) for GAD-7 and -3.8 (-6.0 to -1.5) for PHQ-9 (both p < 0.05). Participant feedback indicated high satisfaction with the MBCT intervention. Conclusions These findings bring preliminary evidence to support the effectiveness of MBCT in improving anxiety and depressive symptoms in people with PD. Larger, randomized-controlled studies are needed to replicate these results. This research was funded by This work was funded by the Parkinson's Foundation and the Mount Zion Health Fund.