Smaller gray matter volume of hippocampus/parahippocampus in elderly people with subthreshold depression: a cross-sectional study

Physical activity, physical frailty and depressive symptoms among Chinese male and female older adults: do different indicators make a difference?

Objectives

Older adults become more inactive and frailer with aging. Physical status is closely linked to mental health, but it is unclear which physical indicator is more strongly associated with depressive symptoms in older adults. The present study aimed to compare relationships between self-reported physical activity, physical frailty (muscle mass, muscle strength, and gait ability) and depressive symptoms in community male and female older adults.

Methods

A total of 1,180 adults aged 60 years and older were recruited to participate in this study from a Chinese community receiving annual check-up service from September 2018 to May 2019. Physical activity was assessed by the International Physical Activity Questionnaire (IPAQ). The Bio-electrical Impedance Analyzer was used to determine the muscle mass. As the indicators of muscle function, grip strength and gait ability were assessed by the dynamometer and Timed Up and Go Test (TUGT), respectively. The 15-item version of Geriatric Depression Scale (GDS-15) was used to examine depressive symptoms. Demographic variables, health status and sleep quality were collected using questionnaire.

Results

11.8% men and 11.9% women reported depressive symptoms. Logistic regression showed that depressive symptoms was associated with low grip strength (OR = 2.42, 95% CI: 1.04-5.63), slow gait ability (OR = 3.60, 95% CI: 1.28-10.13) in older males, and associated with low level of self-reported physical activity (OR = 3.85, 95% CI: 2.00-7.42) in older females. No significant association was found between muscle mass and depressive symptoms.

Conclusion

There were gender differences in the relationship between physical activity, physical frailty, and depressive symptoms. Grip strength and gait ability may be a better indicator of frailty for predicting depressive symptoms in older men while physical activity may be useful in predicting depressive symptoms in older women.

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.

Depressive symptoms in cognitively unimpaired older adults are associated with lower structural and functional integrity in a frontolimbic network

Subclinical depressive symptoms are associated with increased risk of Alzheimer's disease (AD), but the brain mechanisms underlying this relationship are still unclear. We aimed to provide a comprehensive overview of the brain substrates of subclinical depressive symptoms in cognitively unimpaired older adults using complementary multimodal neuroimaging data. We included cognitively unimpaired older adults from the baseline data of the primary cohort Age-Well (n = 135), and from the replication cohort ADNI (n = 252). In both cohorts, subclinical depressive symptoms were assessed using the 15-item version of the Geriatric Depression Scale; based on this scale, participants were classified as having depressive symptoms (>0) or not (0). Voxel-wise between-group comparisons were performed to highlight differences in gray matter volume, glucose metabolism and amyloid deposition; as well as white matter integrity (only available in Age-Well). Age-Well participants with subclinical depressive symptoms had lower gray matter volume in the hippocampus and lower white matter integrity in the fornix and the posterior parts of the cingulum and corpus callosum, compared to participants without symptoms. Hippocampal atrophy was recovered in ADNI, where participants with subclinical depressive symptoms also showed glucose hypometabolism in the hippocampus, amygdala, precuneus/posterior cingulate cortex, medial and dorsolateral prefrontal cortex, insula, and temporoparietal cortex. Subclinical depressive symptoms were not associated with brain amyloid deposition in either cohort. Subclinical depressive symptoms in ageing are linked with neurodegeneration biomarkers in the frontolimbic network including brain areas particularly sensitive to AD. The relationship between depressive symptoms and AD may be partly underpinned by neurodegeneration in common brain regions.

Nutritional therapy can reduce the burden of depression management in low income countries: A review

Depression is a serious mental and mood disorder with global health and economic burden. This burden may be overwhelming in low income countries, although there are insufficient data. Most antidepressant formulations are predicated on the monoamine, neuroendocrine and neuro-inflammation hypotheses, with little or no cognizance to other neurochemicals altered in depression. A nutritional strategy with or without conventional antidepressants is recommended, as nutrition plays vital roles in the onset, severity and duration of depression, with poor nutrition contributing to its pathogenesis. This review discusses nutritional potentials of utilizing omega-3 fatty acids, proteins, vitamins, minerals and herbs or their phytochemicals in the management of depression with the aim of reducing depression burden. Literature search of empirical data in books and journals in data bases including but not limited to PubMed, Scopus, Science Direct, Web of Science and Google Scholar that might contain discussions of sampling were sought, their full text obtained, and searched for relevant content to determine eligibility. Omega-3 fatty and amino acids had significant positive anti-depression outcomes, while vitamins and minerals although essential, enhanced omega-3 fatty and amino acids activities. Some herbs either as whole extracts or their phytochemicals/metabolites had significant positive anti-depression efficacy. Nutrition through the application of necessary food classes or herbs as well as their phytochemicals, may go a long way to effectively manage depression. This therefore will provide inexpensive, natural, and non-invasive therapeutic means with reduced adverse effects that can also be applied alongside clinical management. This nutritional strategy should be given more attention in research, assessment and treatment for those with depression and other mental illness in low income countries, especially in Africa.

Amplitude of low-frequency fluctuation (ALFF) alterations in adults with subthreshold depression after physical exercise: A resting-state fMRI study

BACKGROUND

Physical exercise has been proved to reduce the risk of major depression in Subthreshold depression (StD) individuals effectively, yet little is known about the spontaneous brain activity changes associated with physical exercise.

METHODS

A total of 70 adult subjects, including 38 StD and 32 healthy control (HC) subjects, underwent a resting-state functional magnetic resonance imaging (rs-fMRI) before and after eight-week aerobic exercise respectively. Then, the amplitude of low-frequency fluctuation (ALFF) alterations between the two groups were quantitatively analyzed.

RESULTS

Before exercise intervention, the rs-fMRI data showed increased ALFF of the right putamen in the StD group compared with HC group. After exercise intervention, there was no significant ALFF change observed between the StD and HC groups. The longitudinal ALFF differences from pre- to post- exercise intervention showed significantly decreased ALFF in the right middle and inferior occipital gyrus, right middle and inferior temporal gyrus, right fusiform gyrus (FG), while increased ALFF in the right middle cingulate, right superior parietal louble, right inferior parietal lobule (IPL) (inferior parietal gyrus and supramarginal gyrus), and bilateral precuneus in the StD group. As for HC group, the results showed that decreased ALFF in the right FG and right parahippocampus, while increased ALFF in the right precuneus, right middle cingulate, right supplementary motor area, right superior parietal lobule and right paracentral lobule in the HC group. No significant correlation between changes of ALFF and clinical scale scores in the StD group.

LIMITATIONS

The definitions of StD are varied in terms of different studies, the final sample size was relatively small, and the age range of the subjects in this study was narrow. Meanwhile, the exercise intervention trial was short-term.

CONCLUSIONS

These results further support the standpoint that physical exercise has the potential to reshape the abnormal patterns of spontaneous brain activity in adults with StD.

Altered gray matter volume and functional connectivity in patients with herpes zoster and postherpetic neuralgia

Numerous neuroimaging studies on postherpetic neuralgia (PHN) and herpes zoster (HZ) have revealed abnormalities in brain structure/microstructure and function. However, few studies have focused on changes in gray matter (GM) volume and intrinsic functional connectivity (FC) in the transition from HZ to PHN. This study combined voxel-based morphometry and FC analysis methods to investigate GM volume and FC differences in 28 PHN patients, 25 HZ patients, and 21 well-matched healthy controls (HCs). Compared to HCs, PHN patients exhibited a reduction in GM volume in the bilateral putamen. Compared with HZ patients, PHN patients showed decreased GM volume in the left parahippocampal gyrus, putamen, anterior cingulate cortex, and right caudate and increased GM volume in the right thalamus. However, no regions with significant GM volume changes were found between the HZ and HC groups. Correlation analysis revealed that GM volume in the right putamen was positively associated with illness duration in PHN patients. Furthermore, lower FCs between the right putamen and right middle frontal gyrus/brainstem were observed in PHN patients than in HCs. These results indicate that aberrant GM volumes and FC in several brain regions, especially in the right putamen, are closely associated with chronification from HZ to PHN; moreover, these changes profoundly affect multiple dimensions of pain processing. These findings may provide new insights into the pathophysiological mechanisms of PHN.

The Role of Race in Relations of Social Support to Hippocampal Volumes Among Older Adults

Evidence suggests social support may buffer brain pathology. However, neither its association with hippocampal volume, a marker of Alzheimer's disease risk, nor the role of race in this association has been fully investigated. Multiple regression analyses examined relations of total social support to magnetic resonance imaging-assessed gray matter (GM) hippocampal volumes in the total sample (n = 165; mean age = 68.48 year), and in race-stratified models of African American and White older adults, adjusting for select covariates. Results showed greater social support was associated with greater GM hippocampal volumes among African American older adults only (p < .01). Our findings suggest greater total social support may play a role in supporting the hippocampus, particularly among African American older adults, who had lower hippocampal volumes than their White counterparts. Further research is needed to test these questions longitudinally and examine which aspects of social support may promote hippocampal integrity, specifically.

Preliminary Comparison of Subcortical Structures in Elderly Subclinical Depression: Structural Analysis with 3T MRI

Depression in the elderly population has shown increased likelihood of neurological disorders due to structural changes in the subcortical area. However, further investigation into depression related subcortical changes is needed due to mismatches in structural analysis results between studies as well as scarcities in research regarding subcortical connectivity patterns of subclinical depression populations. This study aims to investigate structural differences in subcortical regions of aged participants with subclinical depression using 3Tesla MRI. In structural analysis, volumes of each subcortical region were measured to observe the volumetric difference and asymmetry between groups, but no significant difference was found. In addition, fractional anisotropy (FA) and apparent diffusion coefficient (ADC) did not show any significant differences between groups. Structural analysis using probabilistic tractography indicated that the connection strength between left nucleus accumbens-right hippocampus, and right thalamus-right caudate was higher in the control group than the subclinical depression group. The differences in subcortical connection strength of subclinical depression groups, have shown to correlate with emotional and cognitive disorders, such as anxiety and memory impairment. We believe that the analysis of structural differences and cross-regional network measures in subcortical structures can help identify neurophysiological changes occurring in subclinical depression.

The effectiveness of Tai Chi on the depressive symptom of young adults with subthreshold depression: a study protocol for a randomized controlled trial

BACKGROUND

Depression is seriously affecting the physical and mental health of young people worldwide. Subthreshold depression, as an early stage of depression, is essential for early prevention and treatment of depression. Tai Chi, as a traditional Chinese mind-body therapy, may become an alternative intervention. However, the neurophysiological mechanism of Tai Chi for young people with subthreshold depression remains unclear, restricting its further promotion and application. Therefore, rigorous randomized clinical trials are needed to further observe the intervention effect of Tai Chi on young adults with subthreshold depression and explore the neurophysiological mechanism.

METHOD/DESIGN

This report describes a two-arm, randomized, parallel controlled trial with allocation concealment and assessor blinding. A total of 64 eligible participants are randomly allocated to the Tai Chi group and the waiting list group in a 1:1 ratio. Participants in the Tai Chi group receive 12 weeks of Tai Chi training, with a total of 36 times and each for 60 min. Specifically, the participants in the waiting list group are requested to maintain their routine lifestyle. In this study, the primary outcome measure is the mean change in scores on the PHQ-9 and HAMD-17 between baseline and 12 weeks; the secondary outcomes are the mean change in the scores on CES-D, CPSS, GAD-7, and PSQI. Besides, the saliva cortisol levels and fMRI are monitored to explore the mechanism of action of Tai Chi on subthreshold depression.

DISCUSSION

The protocol uses a randomized controlled trial to examine the effectiveness of Tai Chi for young adults with subthreshold depression and explore neurophysiological mechanisms. If the test results are positive, it can be verified that Tai Chi can promote the physical and mental health of young adults with subthreshold depression.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR1900028289 . Registered on 17 December 2019.

Linking depressive symptom dimensions to cerebellar subregion volumes in later life

The present study examined the relationship between subthreshold depressive symptoms and gray matter volume in subregions of the posterior cerebellum. Structural magnetic resonance imaging data from 38 adults aged 51 to 80 years were analyzed along with participants' responses to the Center for Epidemiologic Studies Depression Scale. Subscale scores for depressed mood, somatic symptoms, and lack of positive affect were calculated, and multiple regression analyses were used to examine the relationship between symptom dimensions and cerebellar volumes. Greater total depressive symptoms and greater somatic symptoms of depression were significantly related to larger volumes of vermis VI, a region within the salience network, which is altered in depression. Exploratory analyses revealed that higher scores on the lack of positive affect subscale were related to larger vermis VIII volumes. These results support that depressive symptom profiles have unique relationships within the cerebellum that may be important as the field move towards targeted treatment approaches for depression.

Subthreshold depression may exist on a spectrum with major depressive disorder: Evidence from gray matter volume and morphological brain network

BACKGROUND

Subthreshold depression (StD) is a prevalent condition that may increase the risk of incident major depressive disorder (MDD). However, the relationship between StD and MDD remains unclear.

METHODS

A total of 153 adult subjects, including 53 drug-naive MDD, 50 StD and 50 healthy control (HC) subjects, underwent a T1-weighted magnetic resonance imaging scan, and the gray matter volume (GMV) alterations among the three groups were quantitatively analyzed using voxel-based morphometry (VBM). Then, to capture the whole-brain connectivity characteristics, we constructed morphological brain networks (MBN) based on the similarity among brain regions of individual VBM images and compared the network connection strengths among the three groups.

RESULTS

The StD and MDD subjects had similar patterns of GMV reductions in the orbitofrontal cortex and left temporal gyrus, although the magnitude of the reductions was smaller in StD subjects. Moreover, a total of 21 morphological connections were significantly different among the three groups. For the majority of the different connections (15/21), the connection strength of the StD group took an intermediate position between that of the MDD and HC groups.

LIMITATIONS

There is still a lack of a consistent definition of StD, and the age range of the subjects in this study was wide. Meanwhile the mechanisms and biological significance of the MBN remains to be clarified.

CONCLUSIONS

These results may support the hypothesis that depression is better expressed as a spectrum and that StD exists on a spectrum with MDD.

Associations between subclinical depressive symptoms and reduced brain volume in middle-aged to older adults

OBJECTIVES

The associations between subclinical depressive symptoms, as well specific symptom subscales, on brain structure in aging are not completely elucidated. This study investigated the extent to which depressive symptoms were related to brain volumes in fronto-limbic structures in a sample of middle-aged to older adults.

METHOD

Eighty participants underwent structural neuroimaging and completed the Beck Depression Inventory, 2nd Edition (BDI-II), which comprises separate affective, cognitive, and somatic subscales. Gray matter volumes were extracted from the caudal and rostral anterior cingulate, posterior cingulate, hippocampus, and amygdala. Hierarchical regression models examined the relationship between brain volumes and (i) total depressive symptoms and (ii) BDI-II subscales were conducted.

RESULTS

After adjusting for total intracranial volume, race, and age, higher total depressive symptoms were associated with smaller hippocampal volume (p = 0.005). For the symptom subscales, after controlling for the abovementioned covariates and the influence of the other symptom subscales, more somatic symptoms were related to smaller posterior cingulate (p = 0.025) and hippocampal (p < 0.001) volumes. In contrast, the affective and cognitive subscales were not associated with brain volumes in any regions of interest.

CONCLUSION

Our data showed that greater symptomatology was associated with smaller volume in limbic brain regions. These findings provide evidence for preclinical biological markers of major depression and specifically advance knowledge of the relationship between subclinical depressive symptoms and brain volume. Importantly, we observed variations by specific depressive symptom subscales, suggesting a symptom-differential relationship between subclinical depression and brain volume alterations in middle-aged and older individuals.

Long-term trajectories of depressive symptoms in old age: Relationships with sociodemographic and health-related factors

BACKGROUND

This study aimed at depicting the course of depression symptoms over the old age, with a special interest in a) uncovering its relationships with sociodemographic and health-related factors; b) analysing its predictive role on healthy-ageing outcomes later in life.

METHODS

The sample comprised 8317 older adults (46.02% men) from the English Longitudinal Study of Ageing. Robust structural equation modelling was used to identify symptom trajectories and their relationships with time-varying factors. Trajectory class and covariates were used to predict outcomes (quality of life, satisfaction with life, and daily living functioning) in a 2-year follow-up.

RESULTS

Three trajectory classes (so-called, normative, subclinical, chronic symptom trajectories) were identified for both sexes. Rising hearing difficulties and history of psychiatric problems were consistently associated with the chronic symptom trajectory. Lower education level, history of psychiatric problems, and increasing visual difficulties were connected with the subclinical trajectories. Finally, participants with either a subclinical or a chronic symptom trajectory showed worse outcomes than the remaining participants in the follow-up.

CONCLUSION

This study highlighted the presence of varying courses of depression symptoms (each showing some distinctive features from other another) over the old age, pointing to some relevant implications for clinical assessment and treatment prescription.

Cerebral patterns of neuropsychological disturbances in hepatitis C patients

Neuropsychiatric symptoms and cognitive impairment have been consistently reported in patients with hepatitis C virus (HCV) infection. Since the mechanisms behind remain to be established, the present study attempted to assess whether neuropsychological impairments in HCV-infected patients are accompanied by structural alterations in the brain. Therefore, 19 anti-HCV-antibody-positive women with mild liver disease and 16 healthy controls underwent extensive neuropsychological testing and cranial magnetic resonance imaging (MRI) examination. Nine of the patients and five controls were followed up after 6-7 years. Voxel-based morphometry and magnetization transfer imaging were utilized to study HCV-associated structural gray and white matter changes. The HCV-infected patients had significantly worse fatigue and depression scores and significantly poorer performance on attention and memory tests than controls. The patients displayed gray matter (GM) atrophy in the bilateral insula and thalamus and a profound GM volume increases in the cerebellum. Microstructural GM changes in the insula were also evident by a reduced magnetization transfer ratio. Structural white matter changes were observed along several descending and crossing fiber tracts. Follow-up at 7 years revealed increased GM atrophy in the left amygdala and left parahippocampal regions over time. We conclude that our data provide evidence for structural alterations in the brains of patients with chronic HCV infection. Disturbances of cerebellothalamocortical regions and circuits, linking cerebellar projections to the prefrontal cortex through the thalamus, underpin the emotional and cognitive dysfunction characteristically observed in these patients.

Vascular risk modulates the relationship between cerebral amyloid deposition and subjective memory complaints

PURPOSE

We aimed to investigate the relationships of cerebral amyloid beta (Aβ) deposition and neurodegeneration (ND) with subjective memory complaints (SMCs) in cognitively normal (CN) individuals, focusing specially on the modulating effects of vascular risk (VR) on those relationships.

PARTICIPANTS AND METHODS

A total of 230 CN elderly individuals underwent comprehensive clinical assessments including the Subjective Memory Complaints Questionnaire (SMCQ), VR assessment, and multimodal brain imaging including [¹¹C] Pittsburgh compound B positron emission tomography (PET), [¹⁸F] fluorodeoxyglucose-PET, and magnetic resonance imaging.

RESULTS

We found a significant overall positive association between cerebral Aβ retention and SMCQ score. In addition, we found a significant cerebral Aβ retention × VR interaction effect on the SMCQ score. Subgroup analyses showed that the Aβ-SMC association was found only in VR-negative, and not in VR-positive, individuals. We found no relationship between ND and SMCQ.

CONCLUSION

Our findings suggest that SMC in CN elderly individuals reflects early accumulation of Aβ in the brain. Given the modulating effect of VR on the Aβ-SMC relationship, SMC can be used as a meaningful marker of early Aβ deposition in individuals without VR.

Alterations in structural rich-club connectivity of the precuneus are associated with depressive symptoms among individuals with subjective memory complaints

The association between subjective memory complaints (SMCs) and depressive symptoms has been widely reported and both have been regarded as risk factors for dementia, such as Alzheimer's disease (AD). Although SMCs arise as early as in middle age, the exact neural correlates of comorbid depressive symptoms among individuals who are middle-aged and with SMCs have not yet been well investigated. Because rich-club organization of the brain plays a key role in the pathophysiology of various neuropsychiatric disorders, the investigation of rich club organization may provide insight regarding the neurobiological mechanisms of depressive symptoms in SMCs. In the current study, we compared the rich-club organization in the structural brain connectivity between individuals who have SMCs along with depressive symptoms (SMCD) and individuals with SMCs but without depressive symptoms (SMCO). A total of 53 individuals with SMCD and 91 individuals with SMCO participated in the study. For all participants, high-resolution, T1-weighted images and diffusion tensor images were obtained, and the network analysis was performed. Individuals with SMCD had lower connectivity strength between the precuneus and other rich-club nodes than those with SMCO, which was significant after adjusting for potential confounders. Our findings suggest that disruptions of rich-club connectivity strength of the precuenus are associated with depressive symptoms in middle-aged individuals with SMCs. Given that the precuneus is one of the commonly affected regions in the early stages of AD, our findings may imply that the concomitant depressive symptoms in middle-aged individuals with SMCs could reflect structural alterations related to AD.

Abnormal Global Functional Connectivity Patterns in Medication-Free Major Depressive Disorder

Mounting studies have applied resting-state functional magnetic resonance imaging (rs-fMRI) to study major depressive disorder (MDD) and have identified abnormal functional activities. However, how the global functional connectivity patterns change in MDD is still unknown. Using rs-fMRI, we investigated the alterations of global resting-state functional connectivity (RSFC) patterns in MDD using weighted global brain connectivity (wGBC) method. First, a whole brain voxel-wise wGBC map was calculated for 23 MDD patients and 34 healthy controls. Two-sample t-tests were applied to compare the wGBC and RSFC maps and the significant level was set at p < 0.05, cluster-level correction with voxel-level p < 0.001. MDD patients showed significantly decreased wGBC in left temporal pole (TP) and increased wGBC in right parahippocampus (PHC). Subsequent RSFC analyses showed decreased functional interaction between TP and right posterior superior temporal cortex and increased functional interaction between PHC and right inferior frontal gyrus in MDD patients. These results revealed the abnormal global FC patterns and its corresponding disrupted functional connectivity in MDD. Our findings present new evidence for the functional interruption in MDD.

Subthreshold depression among diabetes patients in Beijing: Cross-sectional associations among sociodemographic, clinical, and behavior factors

BACKGROUND

This study explores the prevalence of subthreshold depression (SubD) and its association with factors in type 2 diabetes mellitus (T2DM) patients.

METHODS

This cross-sectional study involved 808 outpatients with T2DM from ten hospitals in Beijing between September 2015 and January 2016. All participants completed the Patient Health Questionnaire 9-item (PHQ-9) to evaluate depressive status, with scores between 5 and 14 considered SubD. Conditional logistic regression was conducted to investigate the variables associated with SubD in T2DM patients.

RESULTS

T2DM patients with SubD comprised 11.6% (n = 94) of the sample. The odd ratios for the variables having significant positive associations with SubD were: being a women (OR = 1.90; 95%CI: 1.09-3.32), divorced/widowed (OR = 3.27; 95%CI: 1.46-7.30), comorbidity of cerebrovascular disease (OR = 2.00; 95%CI: 1.06-3.76), more diabetic complications (OR = 8.04; 95%CI: 2.77-23.31), and higher HbA1c in men (OR = 2.41; 95%CI: 1.25-4.64). Being older (OR = 0.78; 95%CI: 0.62-0.98), exercising more (OR = 0.44; 95%CI: 0.22-0.91) and poverty (OR = 0.36; 95%CI: 0.19-0.69) were negatively related to SubD.

LIMITATIONS

The sample was mainly recruited from hospital settings, which limits generalization. The study's cross-sectional design precludes making causal inferences.

CONCLUSIONS

The proportion of SubD was estimated to be 11.6% among T2DM patients in Beijing. Having more diabetic complications and being divorced/widowed made the odds of having SubD 8-fold and 3-fold higher than not having it, respectively. The relationship between SubD and diabetes necessitates early screening for milder forms of depression, which can alleviate the social burden and individual impairment from major depression or other chronic diseases.

Subclinical depressive symptoms during late midlife and structural brain alterations: A longitudinal study of Danish men born in 1953

We explored whether depressive symptoms measured three times during midlife were associated with structural brain alterations quantified using magnetic resonance imaging measurements of volume, cortical thickness, and intensity texture. In 192 men born in 1953 with depressive symptoms measured at age 51, 56, and 59 years, magnetic resonance imaging was performed at age 59. All data processing was performed using the Freesurfer software package except for the texture-scores that were computed using in-house software. Structural brain alterations and associations between depressive symptoms and brain structure outcomes were tested using Pearson's correlation, t test, and linear regression. Depressive symptoms at age 51 showed clear inverse correlations with total gray matter, pallidum, and hippocampal volume with the strongest estimate for hippocampal volume (r = -.22, p < .01). After exclusion of men (n = 3) with scores in the range of clinical depression the inverse correlation between depressive symptoms and hippocampal volume became insignificant (r = -13, p = .08). Depressive symptoms at age 59 correlated positively with hippocampal and amygdala texture-potential early markers of atrophy. Inverse relations with total gray matter and pallidum volumes lost significance when the analysis was adjusted for intracranial volume. In men, depressive symptoms at age 51 were associated with a reduced volume of the hippocampus at age 59 independent of later symptoms. Amygdala and hippocampal textures might be the early markers for brain alterations associated with depression in midlife.

Alteration of gray matter texture features over the whole brain in medication-overuse headache using a 3-dimentional texture analysis

Background

Imaging studies have provided valuable information in understanding the headache neuromechanism for medication-overuse headache (MOH), and the aim of this study is to investigate altered texture features of MR structural images over the whole brain in MOH using a 3-dimentional texture analysis.

Methods

Brain three-dimensional T1-weighted structural images were obtained from 44 MOH patients and 32 normal controls (NC). The imaging processing included two steps: gray matter (gray images) segment and a 3-dimensional texture features mapping. Voxel-based gray-level co-occurrence matrix (VGLCM) was performed to measure the texture parameters mapping including Contrast, Correlation, Energy, Entropy and inverse difference moment (IDM).

Results

The texture parameters of increased Contrast and Entropy, decreased Energy and IDM were identified in cerebellar vermis of MOH patients compared to NCs. Increased Contrast and decreased Energy were found in left cerebellum. Increased Correlation located in left dorsolateral periaqueductal gray (L-dlPAG), right parahippocampal gyrus (R-PHG), and left middle frontal gyrus (L-MFG) and decreased Correlation located in right superior parietal lobule(R-SPL). Disease duration was positively correlated with Contrast of vermis and negatively correlated with Correlation of R-SPL.HAMD score was negatively correlated with Correlation of R-PHG. MoCA score was positively correlated with Correlation of R-SPL.

Conclusion

The altered textures in gray matter related to pain discrimination and modulation, affective and cognitive processing were helpful in understanding the pathogenesis of MOH. Texture analysis using VGLCM is a sensitive and efficient method to detect subtle gray matter changes in MOH.

Electronic supplementary material

The online version of this article (10.1186/s10194-017-0820-4) contains supplementary material, which is available to authorized users.

Sex Matters: Hippocampal Volume Predicts Individual Differences in Associative Memory in Cognitively Normal Older Women but Not Men

The hippocampus plays a prominent role in associative memory by supporting relational binding and recollection processes. Structural atrophy in the hippocampus is likely to induce associative memory deficits in older adults. Previous studies have primarily focused on average age-related differences in hippocampal structure and memory performance. To date, however, it remains unclear whether individual differences in hippocampal morphometry underlie differential associative memory performance, and whether there are sex differences in the structural correlates of associative memory in healthy older adults. Here, we used voxel-based morphometry (VBM) to examine the extent to which gray matter volume (GMV) of the hippocampus predicts associative memory performance in cognitively normal older adults. Seventy-one participants completed a cued recall paired-associative learning test (PALT), which consists of novel associations and semantically related associations, and underwent magnetic resonance imaging (MRI). We observed worse associative memory performance and larger variability for novel associations than for semantically related associations. The VBM results revealed that higher scores on associative memory for novel associations were related to greater hippocampal GMV across all older adults. When considering men and women separately, the correlation between hippocampal GMV and associative memory performance for novel associations reached significance only in older women. These findings suggest that hippocampal structural volumes may predict individual differences in novel associative memory in older women but not men.

Anatomical brain difference of subthreshold depression in young and middle-aged individuals

BACKGROUND

Subthreshold depression (StD) is associated with substantial functional impairments due to depressive symptoms that do not fully meet the diagnosis of major depressive disorder (MDD). Its high incidence in the general population and debilitating symptoms has recently put it at the forefront of mood disorder research.

AIM

In this study we investigated common volumetric brain changes in both young and middle-aged StD patients.

METHODS

Two cohorts of StD patients, young and middle-aged, (n = 57) and matched controls (n = 76) underwent voxel-based morphometry (VBM).

RESULTS

VBM analysis found that: 1) compared with healthy controls, StD patients showed decreased gray matter volume (GMV) in the bilateral globus pallidus and precentral gyrus, as well as increased GMV in the left thalamus and right rostral anterior cingulate cortex/medial prefrontal cortex; 2) there is a significant association between Center for Epidemiological Studies Depression Scale scores and the bilateral globus pallidus (negative) and left thalamus (positive); 3) there is no interaction between age (young vs. middle-age) and group (StD vs. controls).

CONCLUSIONS

Our findings indicate significant VBM brain changes in both young and middle-aged individuals with StD. Individuals with StD, regardless of age, may share common neural characteristics.

Severity of alcohol dependence is negatively related to hypothalamic and prefrontal cortical gray matter density in heavy drinking smokers

BACKGROUND

While research has examined brain structure in individuals who use alcohol or nicotine, heavy drinking smokers comprise a unique subpopulation of substance users for whom less is known about the relationship between alcohol or nicotine use and structural brain abnormalities.

OBJECTIVES

The present study examined gray matter morphometry in a sample of 39 heavy drinking smokers (24 males, 15 females) in relation to alcohol and nicotine dependence and quantity of use.

METHODS

Traditional voxel-based morphometry techniques were employed for preprocessing of imaging data. One multiple regression analysis for alcohol and nicotine dependence severity and another for alcohol and nicotine quantity of use were conducted, while controlling for age, gender, and total intracranial volume (ICV).

RESULTS

Alcohol dependence severity was significantly negatively associated with gray matter density in the hypothalamus (p < 0.001, uncorrected) and the right superior frontal gyrus (p < 0.001, uncorrected), while controlling for nicotine dependence severity, age, gender, and ICV. There were no significant relationships observed with respect to nicotine dependence severity, the quantity of alcohol use, or the quantity of nicotine use variables and gray matter density.

CONCLUSIONS

These findings suggest that within heavy drinking smokers, alcohol dependence severity is significantly related to alterations in brain structure, while this effect is not seen for the quantity of alcohol or nicotine use, or severity of nicotine dependence. The current findings help clarify the contribution of alcohol and nicotine effects on brain structure, which could aid in understanding their neurocognitive consequences in heavy drinking smokers.

Decreased Subcortical and Increased Cortical Degree Centrality in a Nonclinical College Student Sample with Subclinical Depressive Symptoms: A Resting-State fMRI Study

Abnormal functional connectivity (FC) at rest has been identified in clinical depressive disorder. However, very few studies have been conducted to understand the underlying neural substrates of subclinical depression. The newly proposed centrality analysis approach has been increasingly used to explore the large-scale brain network of mental diseases. This study aimed to identify the degree centrality (DC) alteration of the brain network in subclinical depressive subjects. Thirty-seven candidates with subclinical depression and 34 well-matched healthy controls (HCs) were recruited from the same sample of college students. All subjects underwent a resting-state fMRI (rs-fMRI) scan to assess the DC of the whole brain. Compared with controls, subclinical depressive subjects displayed decreased DC in the right parahippocampal gyrus (PHG), left PHG/amygdala, and left caudate and elevated DC in the right posterior parietal lobule (PPL), left inferior frontal gyrus (IFG) and left middle frontal gyrus (MFG). In addition, by using receiver operating characteristic (ROC) analysis, we determined that the DC values in the regions with altered FC between the two groups can be used to differentiate subclinical depressive subjects from HCs. We suggest that decreased DC in subcortical and increased DC in cortical regions might be the neural substrates of subclinical depression.