Cognitive and immunological effects of yoga compared to memory training in older women at risk for alzheimer's disease

Subjective cognitive decline (SCD) and mild cognitive impairment (MCI) accompanied by cerebrovascular risk factors (CVRFs) are known to increase the risk of developing dementia. Mind-body practices such as yoga and meditation, have been recognized as safe techniques with beneficial effects on cognitive functions in older adults at risk for cognitive decline. We conducted a randomized, controlled trial to assess the efficacy of Kundalini yoga training (KY) compared to memory enhancement training (MET) on mood and cognitive functioning in a group of older women with CVRFs and SCD (clinicaltrials.gov = NCT03503669). The KY intervention consisted of weekly, 60-min in-person classes with a certified instructor for 12 weeks, with a 12-min guided recording for daily homework practice at home. MET involved 12 weekly in-person group classes with 12-min daily homework exercises. Objective and subjective memory performance were the primary outcomes. Peripheral whole blood samples were collected at baseline, 12-weeks, and 24-weeks follow-up for RNA sequencing and cytokine/chemokine assays. A total of 79 patients (KY = 40; MET = 39) were randomized, and 63 completed the 24-week follow-up (KY = 65% completion rate; MET = 95%; χ2(1) = 10.9, p < 0.001). At 24-weeks follow-up, KY yielded a significant, large effect size improvement in subjective cognitive impairment measures compared to MET. KYOn a transcriptional level, at 12- and 24-week follow-up, KY uniquely altered aging-associated signatures, including interferon gamma and other psycho-neuro-immune pathways. Levels of chemokine eotaxin-1, an aging marker, increased over time in MET but not KY participants. These results suggest clinical and biological benefits to KY for SCD, linking changes in cognition to the anti-inflammatory effects of yoga.

Grey matter volume predicts improvement in geriatric depression in response to Tai Chi compared to Health Education

OBJECTIVES

Geriatric depression (GD) is associated with cognitive impairment and brain atrophy. Tai-Chi-Chih (TCC) is a promising adjunct treatment to antidepressants. We previously found beneficial effects of TCC on resting state connectivity in GD. We now tested the effect of TCC on gray matter volume (GMV) change and the association between baseline GMV and clinical outcome.

PARTICIPANTS

Forty-nine participants with GD (>=60 y) underwent antidepressant treatment (38 women).

INTERVENTION

Participants completed 3 months of TCC (N = 26) or health and wellness education control (HEW; N = 23).

MEASUREMENTS

Depression and anxiety symptoms and MRI scans were acquired at baseline and 3-month follow-up. General linear models (GLMs) tested group-by-time interactions on clinical scores. Freesurfer 6.0 was used to process T1-weighted images and to perform voxel-wise whole-brain GLMs of group on symmetrized percent GMV change, and on the baseline GMV and symptom change association, controlling for baseline symptom severity. Age and sex served as covariates in all models.

RESULTS

There were no group differences in baseline demographics or clinical scores, symptom change from baseline to follow-up, or treatment-related GMV change. However, whole-brain analysis revealed that lower baseline GMV in several clusters in the TCC, but not the HEW group, was associated with larger improvements in anxiety. This was similar for right precuneus GMV and depressive symptoms.

CONCLUSIONS

While we observed no effect on GMV due to the interventions, baseline regional GMV predicted symptom improvements with TCC but not HEW. Longer trials are needed to investigate the long-term effects of TCC on clinical symptoms and neuroplasticity.

Regional gray matter volume correlates with anxiety, apathy, and resilience in geriatric depression

OBJECTIVES

Geriatric depression (GD) is associated with significant medical comorbidity, cognitive impairment, brain atrophy, premature mortality, and suboptimal treatment response. While apathy and anxiety are common comorbidities, resilience is a protective factor. Understanding the relationships between brain morphometry, depression, and resilience in GD could inform clinical treatment. Only few studies have addressed gray matter volume (GMV) associations with mood and resilience.

PARTICIPANTS

Forty-nine adults aged >60 years (38 women) with major depressive disorder undergoing concurrent antidepressant treatment participated in the study.

MEASUREMENTS

Anatomical T1-weighted scans, apathy, anxiety, and resilience data were collected. Freesurfer 6.0 was used to preprocess T1-weighted images and qdec to perform voxel-wise whole-brain analyses. Partial Spearman correlations controlling for age and sex tested the associations between clinical scores, and general linear models identified clusters of associations between GMV and clinical scores, with age and sex as covariates. Cluster correction and Monte-Carlo simulations were applied (corrected alpha = 0.05).

RESULTS

Greater depression severity was associated with greater anxiety (r = 0.53, p = 0.0001), lower resilience (r = -0.33, p = 0.03), and greater apathy (r = 0.39, p = 0.01). Greater GMV in widespread, partially overlapping clusters across the brain was associated with reduced anxiety and apathy, as well as increased resilience.

CONCLUSION

Our results suggest that greater GMV in extended brain regions is a potential marker for resilience in GD, while GMV in more focal and overlapping regions may be markers for depression and anxiety. Interventions focused on improving symptoms in GD may seek to examine their effects on these brain regions.

Impact of Yoga Versus Memory Enhancement Training on Hippocampal Connectivity in Older Women at Risk for Alzheimer's Disease

BACKGROUND

Yoga may be an ideal early intervention for those with modifiable risk factors for Alzheimer's disease (AD) development.

OBJECTIVE

To examine the effects of Kundalini yoga (KY) training versus memory enhancement training (MET) on the resting-state connectivity of hippocampal subregions in women with subjective memory decline and cardiovascular risk factors for AD.

METHODS

Participants comprised women with subjective memory decline and cardiovascular risk factors who participated in a parent randomized controlled trial (NCT03503669) of 12-weeks of KY versus MET and completed pre- and post-intervention resting-state magnetic resonance imaging scans (yoga: n = 11, age = 61.45±6.58 years; MET: n = 11, age = 64.55±6.41 years). Group differences in parcellated (Cole-anticevic atlas) hippocampal connectivity changes (post- minus pre-intervention) were evaluated by partial least squares analysis, controlling for age. Correlations between hippocampal connectivity and perceived stress and frequency of forgetting (assessed by questionnaires) were also evaluated.

RESULTS

A left anterior hippocampal subregion assigned to the default mode network (DMN) in the Cole-anticevic atlas showed greater increases in connectivity with largely ventral visual stream regions with KY than with MET (p < 0.001), which showed associations with lower stress (p < 0.05). Several posterior hippocampal subregions assigned to sensory-based networks in the Cole-anticevic atlas showed greater increases in connectivity with regions largely in the DMN and frontoparietal network with MET than with KY (p < 0.001), which showed associations with lower frequency of forgetting (p < 0.05).

CONCLUSION

KY training may better target stress-related hippocampal connectivity, whereas MET may better target hippocampal sensory-integration supporting better memory reliability, in women with subjective memory decline and cardiovascular risk factors.

Impact of Tai Chi as an adjunct treatment on brain connectivity in geriatric depression

BACKGROUND

As an adjunct to antidepressant treatment, Tai Chi Chih (TCC) is superior to health education and wellness (HEW) training in improving the general health of patients with geriatric depression (GD). This study investigated the brain connectivity changes associated with TCC and HEW in combination with antidepressant treatment in patients with GD.

METHODS

Forty patients with GD under stable antidepressant treatment underwent TCC training (n = 21) or HEW training (n = 19) for 12 weeks, and completed baseline and 3-month follow-up resting state magnetic resonance imaging scans. Within-group and between-group differences in parcel-to-parcel connectivity changes with intervention were evaluated by general linear modeling. Relationships between significant connectivity changes and symptom/resilience improvement were evaluated by partial least squares correlation analysis.

RESULTS

Significantly greater increases in connectivity with TCC than with HEW (FDR-corrected p < .05) were observed for 167 pairwise connections, most frequently involving the default mode network (DMN). In both groups, increased connectivity involving largely DMN regions was significantly and positively correlated with improvement in symptoms/resilience.

LIMITATIONS

The sample size was relatively small, mainly due to neuroimaging contraindications (e.g., implants). Additionally, the standard antidepressant treatment varied greatly among patients, adding heterogeneity.

CONCLUSIONS

Non-pharmacological adjuncts, such as TCC, may enhance DMN connectivity changes associated with improved depressive symptoms and psychological resilience in the treatment of GD.

Yoga Prevents Gray Matter Atrophy in Women at Risk for Alzheimer's Disease: A Randomized Controlled Trial

BACKGROUND

Female sex, subjective cognitive decline (SCD), and cardiovascular risk factors (CVRFs) are known risk factors for developing Alzheimer's disease (AD). We previously demonstrated that yoga improved depression, resilience, memory and executive functions, increased hippocampal choline concentrations, and modulated brain connectivity in older adults with mild cognitive impairment.

OBJECTIVE

In this study (NCT03503669), we investigated brain gray matter volume (GMV) changes in older women with SCD and CVRFs following three months of yoga compared to memory enhancement training (MET).

METHODS

Eleven women (mean age = 61.45, SD = 6.58) with CVRF and SCD completed twelve weeks of Kundalini Yoga and Kirtan Kriya (KY + KK) while eleven women (mean age = 64.55, SD = 6.41) underwent MET. Anxiety, resilience, stress, and depression were assessed at baseline and 12 weeks, as were T1-weighted MRI scans (Siemens 3T Prisma scanner). We used Freesurfer 6.0 and tested group differences in GMV change, applying Monte-Carlo simulations with alpha = 0.05. Region-of-interest analysis was performed for hippocampus and amygdala.

RESULTS

Compared to KY + KK, MET showed reductions in GMV in left prefrontal, pre- and post-central, supramarginal, superior temporal and pericalcarine cortices, right paracentral, postcentral, superior and inferior parietal cortices, the banks of the superior temporal sulcus, and the pars opercularis. Right hippocampal volume increased after yoga but did not survive corrections.

CONCLUSION

Yoga training may offer neuroprotective effects compared to MET in preventing neurodegenerative changes and cognitive decline, even over short time intervals. Future analyses will address changes in functional connectivity in both groups.

A Randomized Controlled Trial of Tai Chi Chih or Health Education for Geriatric Depression

OBJECTIVES

Geriatric depression is difficult to treat and frequently accompanied by treatment resistance, suicidal ideations and polypharmacy. New adjunctive mind-body treatment strategies can improve clinical outcomes in geriatric depression and reduce risk for side-effects of pharmacological treatments.

METHODS

We conducted a 3-month randomized controlled trial to assess the efficacy and tolerability of combining Tai Chi Chih (TCC) or Health Education and Wellness training (HEW) with the stable standard antidepressant treatment on mood and cognitive functioning in depressed older adults (NCT02460666). Primary outcome was change in depression as assessed by the Hamilton Rating Scale for Depression (HAM-D) post-treatment. Remission was defined as HAM-D ≤ 6; naturalistic follow-up continued for 6 months. We also assessed psychological resilience, health-related quality of life and cognition.

RESULTS

Of the 178 randomized participants, 125 completed the 3-month assessment and 117 completed the 6-month assessment. Dropout and tolerability did not differ between groups. Remission rate within TCC was 35.5% and 33.3%, compared to 27.0% and 45.8% in HEW, at 3 and 6 months respectively (χ²(1) = 1.0, p = 0.3; χ²(1) = 1.9, p =0.2). Both groups improved significantly on the HAM-D at 3 and 6 months. TCC demonstrated a greater improvement in general health compared to HEW.

CONCLUSIONS

Both TCC and HEW combined with a standard antidepressant treatment improved symptoms of depression in older adults. While TCC was superior to HEW in improving general health, we did not find group differences in improvement in mood and cognition.

Gut Microbiome Diversity and Abundance Correlate with Gray Matter Volume (GMV) in Older Adults with Depression

Growing evidence supports the concept that bidirectional brain–gut microbiome interactions play an important mechanistic role in aging, as well as in various neuropsychiatric conditions including depression. Gray matter volume (GMV) deficits in limbic regions are widely observed in geriatric depression (GD). We therefore aimed to explore correlations between gut microbial measures and GMV within these regions in GD. Sixteen older adults (>60 years) with GD (37.5% female; mean age, 70.6 (SD = 5.7) years) were included in the study and underwent high-resolution T1-weighted structural MRI scanning and stool sample collection. GMV was extracted from bilateral regions of interest (ROI: hippocampus, amygdala, nucleus accumbens) and a control region (pericalcarine). Fecal microbiota composition and diversity were assessed by 16S ribosomal RNA gene sequencing. There were significant positive associations between alpha diversity measures and GMV in both hippocampus and nucleus accumbens. Additionally, significant positive associations were present between hippocampal GMV and the abundance of genera Family_XIII_AD3011_group, unclassified Ruminococcaceae, and Oscillibacter, as well as between amygdala GMV and the genera Lachnospiraceae_NK4A136_group and Oscillibacter. Gut microbiome may reflect brain health in geriatric depression. Future studies with larger samples and the experimental manipulation of gut microbiome may clarify the relationship between microbiome measures and neuroplasticity.

Women who breastfeed exhibit cognitive benefits after age 50

Background and objectives

Women who breastfeed may experience long-term benefits for their health in addition to the more widely appreciated effects on the breastfed child. Breastfeeding may induce long-term effects on biopsychosocial systems implicated in brain health. Also, due to diminished breastfeeding in the postindustrial era, it is important to understand the lifespan implications of breastfeeding for surmising maternal phenotypes in our species’ collective past. Here, we assess how women’s breastfeeding history relates to postmenopausal cognitive performance.

Methodology

A convenience sample of Southern California women age 50+ was recruited via two clinical trials, completed a comprehensive neuropsychological test battery and answered a questionnaire about reproductive life history. General linear models examined whether cognitive domain scores were associated with breastfeeding in depressed and non-depressed women, controlling for age, education and ethnicity.

Results

Women who breastfed exhibited superior performance in the domains of Learning, Delayed Recall, Executive Functioning and Processing Speed compared to women who did not breastfeed (P-values 0.0003–0.015). These four domains remained significant in analyses limited to non-depressed and parous subsets of the cohort. Among those depressed, only Executive Functioning and Processing Speed were positively associated with breastfeeding.

Conclusions and implications

We add to the growing list of lifespan health correlates of breastfeeding for women’s health, such as the lower risk of type-2 diabetes, cardiovascular disease and breast cancer. We surmise that women’s postmenopausal cognitive competence may have been greater in past environments in which breastfeeding was more prevalent, bolstering the possibility that postmenopausal longevity may have been adaptive across human evolutionary history.

Lay Summary

Breastfeeding may affect women’s cognitive performance. Breastfeeding’s biological effects and psychosocial effects, such as improved stress regulation, could exert long-term benefits for the mother’s brain. We found that women who breastfed performed better on a series of cognitive tests in later life compared to women who did not breastfeed.

Memantine can protect against inflammation-based cognitive decline in geriatric depression

INTRODUCTION

Geriatric depression is frequently accompanied by cognitive complaints and inflammation that increase risk for treatment-resistant depression and dementia. Memantine, a neuroprotective drug, can improve depression, inflammation, and help prevent cognitive decline. In our six-month clinical trial, escitalopram/memantine (ESC/MEM) improved mood and cognition compared to escitalopram/placebo treatment (ESC/PBO; NCT01902004). In this report, we examined the impact of baseline inflammation on mood and cognitive outcomes.

MATERIALS AND METHODS

We measured a panel of inflammatory cytokine markers using Human 38-plex magnetic cytokine/chemokine kits (EMD Millipore, HCYTMAG-60K-PX38) in 90 older adults 60 years and older with major depression enrolled in a 6-month double-blind placebo-controlled trial of escitalopram ​+ ​memantine (ESC/MEM) in depressed older adults with subjective memory complaints. Four cytokine factors were derived and linear models were estimated to examine the predictive ability of cytokine levels on treatment induced change in depression and cognition.

RESULTS

Of the 90 randomized participants, 62 completed the 6-month follow up assessment. Both groups improved significantly on depression severity (HAM-D score), but not on cognitive outcomes at six months. Cytokine factor scores were not significantly different between ESC/MEM (n ​= ​45) and ESC/PBO (n ​= ​45) at baseline. Pro-inflammatory biomarkers at baseline predicted a decline in executive functioning in the ESC/PBO group but not in the ESC/MEM group, interaction F(1,52) ​= ​4.63, p ​= ​.04.

DISCUSSION

In this exploratory analysis, the addition of memantine to escitalopram provided a protective effect on executive functioning in older depressed adults. Future studies are needed to replicate the association of cytokine markers to antidepressant and neuroprotective treatment-related change in cognition in geriatric depression.

Regional White Matter Integrity Predicts Treatment Response to Escitalopram and Memantine in Geriatric Depression: A Pilot Study

Background: Geriatric depression with subjective memory complaints increases the risk for Alzheimer's Disease. Memantine, a neuroprotective drug, can improve depression and help prevent cognitive decline. In our 6-months clinical trial, escitalopram/memantine (ESC/MEM) improved mood and cognition compared to escitalopram/placebo treatment (ESC/PBO; NCT01902004). In this report, we investigated whether baseline brain white matter integrity in fronto-limbic-striatal tracts can predict clinical outcomes using fractional anisotropy (FA). Methods: Thirty-eight older depressed adults (mean age = 70.6, SD = 7.2) were randomized to ESC/MEM or ESC/PBO and underwent diffusion-weighted imaging (DWI) at 3 Tesla at baseline. Mood was assessed using the Hamilton Depression Rating Scale (HAMD), apathy using the Apathy Evaluation Scale (AES) and anxiety using the Hamilton Anxiety Scale (HAMA) at baseline and 6-months follow-up. FA was extracted from seven tracts of interest (six in each hemisphere and one commissural tract) associated with geriatric depression. Non-parametric General Linear Models were used to examine group differences in the association between FA and symptom improvement, controlling for age, sex, baseline symptom scores and scanner model, correcting for false discovery rate (FDR). Post-hoc tests further investigated group differences in axial, mean and radial diffusivity (AD, MD, and RD, respectively). Lastly, we performed an exploratory whole-brain model to test whether FA might be related to treatment response with memantine. Results: There were no differences in remission rates or HAMD change between groups. In bilateral anterior and posterior internal capsule tracts and bilateral inferior and right superior fronto-occipital (IFO and SFO) fasciculus, higher FA was associated with larger improvements in depressive symptoms for ESC/MEM, but not ESC/PBO, correcting for FDR. Lower MD in the left IFO and RD in the right anterior internal capsule were associated with improved treatment responses. We found no significant associations in the whole-brain analysis. Limitations: Included small sample size and high dropout. Conclusions: Higher baseline FA and lower RD and MD in hypothesized fronto-limbic-striatal tracts predicted greater improvement in mood and anxiety with ESC/MEM compared to ESC/PBO in geriatric depression. FA as a biomarker for white matter integrity may serve as a predictor of treatment response but requires confirmation in larger future studies.

Cortical thickness increases with levomilnacipran treatment in a pilot randomised double-blind placebo-controlled trial in late-life depression

BACKGROUND

Late-life depression (LLD) is associated with significant medical comorbidity, cognitive impairment, and suboptimal treatment response compared to depression experienced earlier in life. Levomilnacipran (LVM) is a novel antidepressant the effects of which on neuroplasticity have not yet been investigated. We investigated the effect of LVM on cortical thickness in a pilot randomised placebo-controlled trial in LLD.

METHODS

Twenty-nine adults (≥ 60 years) with major depression (48.3% female; mean age = 71.5 ± 5.8 years; mean education = 16.0 ± 1.7 years) were randomised to either LVM or placebo for 12 weeks. T1-weighted images were acquired at baseline and 12 weeks. Thirteen subjects (six LVM and seven placebo) completed the study. Group differences in cortical thickness change across the study period were evaluated, with age and total intracranial volume included as covariates.

RESULTS

Dropout rates did not differ significantly between groups. The LVM group had significantly more side effects, but no serious adverse events were reported. Lower LVM dose (≤ 40 mg) was better tolerated than higher doses (80-120 mg). Additionally, the LVM group showed a larger increase in cortical thickness in the right postcentral gyrus (primary somatosensory), supramarginal gyrus (sensory association region), and lateral occipital cortex (visual cortex) compared to the placebo group and greater reductions in the left insula.

CONCLUSIONS

LVM may be less tolerable by older adults with depression and the effects on cortical thickness across sensory and sensory association regions may be related to the experience of side effects. Larger studies are necessary to evaluate treatment efficacy, tolerability, and neural effects of LVM in LLD.