Horticultural Therapy Reduces Biomarkers of Immunosenescence and Inflammaging in Community-Dwelling Older Adults: A Feasibility Pilot Randomized Controlled Trial.

BACKGROUND: With the challenges that aging populations pose to health care, interventions that facilitate alleviation of age-related morbidities are imperative. A prominent risk factor for developing age-related morbidities is immunosenescence, characterized by increased chronic low-grade inflammation, resulting in T-cell exhaustion and senescence. Contact with nature and associated physical activities have been shown to boost immunity in older adults and may be promoted in the form of horticultural therapy (HT). We aimed to examine the effects of HT on immunosenescence. METHOD: We conducted a randomized controlled trial with 59 older adults assigned to either the HT intervention or waitlist control group. Older adults in the HT intervention group underwent HT intervention program over 6 months. Venous blood was drawn at baseline and at the third and sixth month from the commencement of this study. For participants who attended all 3 blood collection time points (HT: n = 22; waitlist: n = 24), flow cytometry analysis was performed on whole blood samples to evaluate the kinetics of lymphocyte subsets over the intervention period, revealing the composition of CD4+ and CD8+ subsets expressing exhaustion markers-CD57, CTLA4, and KLRG1. Enzyme-linked immunosorbent assays were employed to measure changes in plasma IL-6 levels. RESULTS: HT is associated with increased numbers of naive CD8+ T cells and fewer CTLA4-expressing terminally differentiated effector CD4+ and CD8+ memory T cells re-expressing CD45RA (TEMRA). Furthermore, IL-6 levels were reduced during HT, and the frequencies of naive and TEMRA CD8+ T cells were found to be associated with IL-6 levels. CONCLUSION: HT is associated with a reduction in the levels of biomarkers that measure the extent of T-cell exhaustion and inflammaging in older adults. The positive effects of HT on T-cell exhaustion were associated with the reduction of IL-6 levels.

Effects of choral singing versus health education on cognitive decline and aging: a randomized controlled trial.

We conducted a randomized controlled trial to examine choral singing's effect on cognitive decline in aging. Older Singaporeans who were at high risk of future dementia were recruited: 47 were assigned to choral singing intervention (CSI) and 46 were assigned to health education program (HEP). Participants attended weekly one-hour choral singing or weekly one-hour health education for two years. Change in cognitive function was measured by a composite cognitive test score (CCTS) derived from raw scores of neuropsychological tests; biomarkers included brain magnetic resonance imaging, oxidative damage and immunosenescence. The average age of the participants were 70 years and 73/93 (78.5%) were female. The change of CCTS from baseline to 24 months was 0.05 among participants in the CSI group and -0.1 among participants in the HEP group. The between-group difference (0.15, p=0.042) became smaller (0.12, p=0.09) after adjusting for baseline CCTS. No between-group differences on biomarkers were observed. Our data support the role of choral singing in improving cognitive health in aging. The beneficial effect is at least comparable than that of health education in preventing cognitive decline in a community of elderly people. Biological mechanisms underlying the observed efficacy should be further studied.

Mindfulness improves inflammatory biomarker levels in older adults with mild cognitive impairment: a randomized controlled trial.

Few randomized controlled trials investigated the effects of mindfulness intervention on older adults diagnosed with mild cognitive impairment (MCI). Furthermore, there have been hypotheses and theoretical mechanisms on the benefits of mindfulness intervention on biomarkers of stress, inflammation, and neuroplasticity implicated in MCI that warrant empirical evidence. We conducted a pilot randomized controlled trial to examine whether Mindful Awareness Practice (MAP) improved biomarker levels in older adults with MCI. Fifty-five community-dwelling older adults aged 60 and above were randomized into either the treatment arm, MAP, or the active control arm, the health education program (HEP). Researchers who were blinded to treatment allocation assessed the outcomes at baseline, 3-month, and 9-month follow-ups. Linear-mixed models were used to examine the effect of MAP on biomarker levels. MAP participants had significantly decreased high-sensitivity c-reactive protein (hs-CRP) levels at 9-month (ß = -0.307, 95% CI = -0.559 to -0.054 P = 0.018). Exploratory sub-group analyses by sex showed significantly decreased hs-CRP in females only (ß = -0.445, 95% CI = -0.700 to -0.189, P = 0.001), while stratification by MCI subtype showed hs-CRP decreased only in amnestic-MCI (aMCI) (ß = -0.569, 95% CI = -1.000 to -0.133, P = 0.012). Although total sample analyses were not significant, males had significantly decreased interleukin (IL)-6 (ß = -1.001, 95% CI = -1.761 to -0253, P = 0.011) and IL-1ß (ß = -0.607, 95% CI = -1.116 to -0.100, P = 0.021) levels at 3-month and non-significant improvements at 9-month time-point. MAP improved inflammatory biomarkers in sex- and MCI subtype-specific manners. These preliminary findings suggest the potential of mindfulness intervention as a self-directed and low-cost preventive intervention in improving pathophysiology implicated in MCI.

Assessment of Sarcopenia Among Community-Dwelling At-Risk Frail Adults Aged 65 Years and Older Who Received Multidomain Lifestyle Interventions: A Secondary Analysis of a Randomized Clinical Trial.

Importance: There is little understanding of the outcomes associated with active lifestyle interventions for sarcopenia among older persons. Objective: To determine the association of 6-month multidomain lifestyle interventions (physical exercise, nutritional enhancement, cognitive training, combined treatment, and standard care) with change in sarcopenia status and physical function among adults 65 years and older. Design, Setting, and Participants: Post hoc secondary analysis of a parallel-group randomized clinical trial conducted from September 1, 2012, to September 1, 2014, at community centers providing services to elderly individuals in Singapore. Participants included a subsample of 92 community-dwelling prefrail or frail older persons with sarcopenia aged 65 years and older. Data were analyzed from June 1, 2017, to January 1, 2018. Interventions: The 5 intervention groups were a 6-month duration of physical exercise that included resistance and balance training, nutritional enhancement with a commercial oral nutrition supplement formula, cognitive training, a combination of the preceding 3 interventions, and standard care (control). Main Outcomes and Measures: Primary outcomes were changes in sarcopenia status and its components, appendicular skeletal muscle index (ASMI), knee extension strength (KES), and gait speed (GS) at 3 months and 6 months following the intervention. Sarcopenia was defined as the presence of both low ASMI and low KES and/or GS. Results: In 92 participants with sarcopenia, the mean (SD) age was 70.0 (4.7) years and 59 (64.1%) were female. Seventy-eight participants received active interventions and 14 received standard care. Of 92 total participants, the number who remained sarcopenic was reduced to 48 (of 73) after 3 months and 51 (of 75) after 6 months of intervention, indicating that 25 of 92 participants (27.2%) experienced sarcopenia reduction at 3 months and 24 of 92 (26.1%) had sarcopenia reduction at 6 months. Low KES was present in 88 of 92 patients (95.6%), and low GS in 30 of 92 patients (32.6%) at baseline. Among the components of sarcopenia, GS had the greatest change associated with active interventions, with 22 of 30 participants (73.3%) free of low GS at 6 months; in comparison, 17 of 88 participants (19.3%) were free of low KES at 6 months and 7 of 92 participants (7.6%) were free of low ASMI at 6 months. Men experienced greater reduction in sarcopenia than women (χ2 = 5.925; P = .02), as did those with younger age (t = -2.078; P = .04) or higher ASMI (mean [SD] ASMI, 5.74 [0.77] vs 5.14 [0.77] kg/m2; P = .002). Participants in the active intervention group experienced statistically significant decreases in sarcopenia score and its components at 3 months and 6 months from baseline (F = 14.138; P < .001), but the intervention was not associated with significant differences in ASMI, KES, and GS vs standard care. Conclusions and Relevance: This study suggests that older persons with sarcopenia are responsive to the effects of multidomain lifestyle interventions. Sarcopenia reduction was most pronounced through improved gait speed, and occurred more among those who were male, were younger, or had greater muscle mass.

Effects of Horticultural Therapy on Asian Older Adults: A Randomized Controlled Trial.

The effect of horticultural therapy (HT) on immune and endocrine biomarkers remains largely unknown. We designed a waitlist-control randomized controlled trial to investigate the effectiveness of HT in improving mental well-being and modulating biomarker levels. A total of 59 older adults was recruited, with 29 randomly assigned to the HT intervention and 30 to the waitlist control group. The participants attended weekly intervention sessions for the first 3 months and monthly sessions for the subsequent 3 months. Biological and psychosocial data were collected. Biomarkers included IL-1ß, IL-6, sgp-130, CXCL12/SDF-1α, CCL-5/RANTES, BDNF (brain-derived neurotrophic factor), hs-CRP, cortisol and DHEA (dehydroepiandrosterone). Psychosocial measures examined cognitive functions, depression, anxiety, psychological well-being, social connectedness and satisfaction with life. A significant reduction in plasma IL-6 level (p = 0.02) was observed in the HT intervention group. For the waitlist control group, significant reductions in plasma CXCL12 (SDF-1α) (p = 0.003), CXCL5 (RANTES) (p = 0.05) and BDNF (p = 0.003) were observed. A significant improvement in social connectedness was also observed in the HT group (p = 0.01). CONCLUSION: HT, in reducing plasma IL-6, may prevent inflammatory disorders and through maintaining plasma CXCL12 (SDF-1α), may maintain hematopoietic support to the brain. HT may be applied in communal gardening to enhance the well-being of older adults.