ournal Club: Randomised Controlled Trials on Psychosocial Interventions to Promote Mental Health of Community-Dwelling Elderly

Events   18 January, 2018

Date: 18 January 2018

Time: 8-9AM

Venue: Seminar Room T09-04, Level 9, NUHS Tower Block

Speaker: Mr Ng Kheng Siang, PhD candidate, Department of Pharmacology, NUS

Chairperson:  A/Prof Rathi Mahendren, Associate Professor and Senior Consultant, Dept of Psychological Medicine, NUH

Brief Abstract:

Introduction: There have been contradicting reports on the direction of change in peripheral brain-derived neurotrophic factor (BDNF) levels in dementia. Additionally, the current dearth of literature on how mindfulness practice and horticultural therapy may modulate the cognition and psychological well-being of elderly respectively, prompted us to formulate the hypothesis that Mindful Awareness Practice (MAP) and Horticultural Therapy (HT), could enhance cognition and psychological well-being of Singaporean community-dwelling elderly, respectively.

Methods: Systematic review, meta-analysis and meta-regression were utilised to examine the aggregate serum BDNF level. Subsequently, both RCTs conducted had primary outcome measurements of biomarkers candidates, which included BDNF, cytokines, hormones and neuroprotective factors and psychometric measures. 

Results: We found significantly decreased levels of BDNF in patients with Alzheimer’s Disease (AD). No significant differences were observed between AD and mild cognitive impairment (MCI), and between MCI and healthy control groups. For the two trials, MAP-RCT elicited significant improvements in the hs-CRP levels (β= -.26, p=.04), attention (3-month: β=1.29, p=.01) & (9-month: β=2.02, p<.001) and recognition memory (β=1.41, p=.04). Whereas for HT-RCT, the levels of the biomarkers interleukin (IL)-6 (p=.02) had been significantly decreased and the levels of CXCL12 (SDF-1α) (p=.003), CXCL5 (RANTES) (p=.05) and BDNF (p=0.003) maintained after the intervention. Significant improvements in the sub-scale “positive relations with others” were also observed in the HT arm (p=0.01 & p<.001).

Conclusion: The meta-analysis supported the hypothesized direction of change in serum BDNF levels in these three groups of subjects. For the trials, both interventions were effective in improving the scores of the respective psychometric measures. Improvements in the biomarkers also provided biological evidence and plausible underlying mechanisms of the interventions. In all, the findings of these two RCTs supported the nationwide expansion of the interventions in the form of dementia prevention program (for MAP-RCT) and therapeutic gardens (for HT-RCT).