Depressive symptoms, brain volumes and subclinical cerebrovascular disease in postmenopausal women: the Women's Health Initiative MRI Study

A fNIRS investigation of menopausal-related symptoms and brain cortical activity in menopause

BACKGROUND

This study aimed to delineate the association between menopausal-related symptoms and brain cortical hemodynamics in peri-postmenopause women.

METHODS

Cross-sectional data from a total of 358 Han-Chinese women who visited the Menopause Clinic in the Shanghai Sixth People's Hospital from August 2019 to August 2022. Menopausal-related symptoms were analyzed through Kupperman index (KMI) scale and PSQI scale, while cerebral blood flow was measured using a functional near-infrared spectroscopy (fNIRS). Multiple linear regression model was used to assess the risk factors for subregions of brain hemodynamic response.

RESULTS

After adjusting for confounding factors, we identified that menopausal symptom (B = -1.575, 95 % CI (-2.661, -0.488), p = 0.005) and duration of menopause (B = -14.583, 95 % CI (-26.753, -4.192), p = 0.007) were independently associated with the lower brain hemodynamic response in the prefrontal lobe, while in the temporal lobe, overweight (BMI ≥ 24 kg/m2) was negatively associated with the lower brain cortical activity (B = -36.882, 95 % CI (-72.708, -1.056), p = 0.044) after adjusting for other confounding variables.

CONCLUSIONS

Our findings proposed that menopausal symptom and overweight should be attached great importance to the postmenopausal women, which provides clinical evidence for the feasible early detection and effective prevention such as menopausal hormone therapy (MHT) of brain health in postmenopausal women.

Role of estrogen in sex differences in memory, emotion and neuropsychiatric disorders

Estrogen regulates a wide range of neuronal functions in the brain, such as dendritic spine formation, remodeling of synaptic plasticity, cognition, neurotransmission, and neurodevelopment. Estrogen interacts with intracellular estrogen receptors (ERs) and membrane-bound ERs to produce its effect via genomic and non-genomic pathways. Any alterations in these pathways affect the number, size, and shape of dendritic spines in neurons associated with psychiatric diseases. Increasing evidence suggests that estrogen fluctuation causes changes in dendritic spine density, morphology, and synapse numbers of excitatory and inhibitory neurons differently in males and females. In this review, we discuss the role of estrogen hormone in rodents and humans based on sex differences. First, we explain estrogen role in learning and memory and show that a high estrogen level alleviates the deficits in learning and memory. Secondly, we point out that estrogen produces a striking difference in emotional memories in men and women, which leads them to display sex-specific differences in underlying neuronal signaling. Lastly, we discuss that fluctuations in estrogen levels in men and women are related to neuropsychiatric disorders, including schizophrenia, autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), bipolar disorder (BPD), major depressive disorder (MDD), substance use disorder (SUD), and anxiety disorders.

Adherence to a MIND-Like Dietary Pattern, Long-Term Exposure to Fine Particulate Matter Air Pollution, and MRI-Based Measures of Brain Volume: The Women's Health Initiative Memory Study-MRI

BACKGROUND

Previous studies suggest that certain dietary patterns and constituents may be beneficial to brain health. Airborne exposures to fine particulate matter [particulate matter with aerodynamic diameter ≤ 2.5 μ m (PM 2.5 )] are neurotoxic, but the combined effects of dietary patterns and PM 2.5 have not been investigated.

OBJECTIVES

We examined whether previously reported association between PM 2.5 exposure and lower white matter volume (WMV) differed between women whose usual diet during the last 3 months before baseline was more or less consistent with a Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND)-like diet, a dietary pattern that may slow neurodegenerative changes.

METHODS

This study included 1,302 U.S. women who were 65-79 y old and free of dementia in the period 1996-1998 (baseline). In the period 2005-2006, structural brain magnetic resonance imaging (MRI) scans were performed to estimate normal-appearing brain volumes (excluding areas with evidence of small vessel ischemic disease). Baseline MIND diet scores were derived from a food frequency questionnaire. Three-year average PM 2.5 exposure prior to MRI was estimated using geocoded participant addresses and a spatiotemporal model.

RESULTS

Average total and temporal lobe WMVs were 0.74   cm 3 [95% confidence interval (CI): 0.001, 1.48) and 0.19   cm 3 (95% CI: 0.002, 0.37) higher, respectively, with each 0.5-point increase in the MIND score and were 4.16   cm 3 (95% CI: - 6.99 , - 1.33 ) and 1.46   cm 3 (95% CI: - 2.16 , - 0.76 ) lower, respectively, with each interquartile range (IQR) (IQR = 3.22   μ g / m 3 ) increase in PM 2.5 . The inverse association between PM 2.5 per IQR and WMV was stronger (p -interaction < 0.001 ) among women with MIND scores below the median (for total WMV, - 12.47   cm 3 ; 95% CI: - 17.17 , - 7.78 ), but absent in women with scores above the median (0.16   cm 3 ; 95% CI: - 3.41 , 3.72), with similar patterns for WMV in the frontal, parietal, and temporal lobes. For total cerebral and hippocampus brain volumes or WMV in the corpus callosum, the associations with PM 2.5 were not significantly different for women with high MIND scores and women with low MIND scores.

DISCUSSION

In this cohort of U.S. women, PM 2.5 exposure was associated with lower MRI-based WMV, an indication of brain aging, only among women whose usual diet was less consistent with the MIND-like dietary pattern at baseline. https://doi.org/10.1289/EHP8036.

Brain Structure and Subclinical Symptoms: A Dimensional Perspective of Psychopathology in the Depression and Anxiety Spectrum

Human psychopathology is the result of complex and subtle neurobiological alterations. Categorial DSM or ICD diagnoses do not allow a biologically founded and differentiated description of these diverse processes across a spectrum or continuum, emphasising the need for a scientific and clinical paradigm shift towards a dimensional psychiatric nosology. The subclinical part of the spectrum is, however, of special interest for early detection of mental disorders. We review the current evidence of brain structural correlates (grey matter volume, cortical thickness, and gyrification) in non-clinical (psychiatrically healthy) subjects with minor depressive and anxiety symptoms. We identified 16 studies in the depressive spectrum and 20 studies in the anxiety spectrum. These studies show effects associated with subclinical symptoms in the hippocampus, anterior cingulate cortex, and anterior insula similar to major depression and changes in amygdala similar to anxiety disorders. Precuneus and temporal areas as parts of the default mode network were affected specifically in the subclinical studies. We derive several methodical considerations crucial to investigations of brain structural correlates of minor psycho(patho)logical symptoms in healthy participants. And we discuss neurobiological overlaps with findings in patients as well as distinct findings, e.g. in areas involved in the default mode network. These results might lead to more insight into the early pathogenesis of clinical significant depression or anxiety and need to be enhanced by multi-centre and longitudinal studies.

Neural substrates for late-life depression: A selective review of structural neuroimaging studies

Recent neuroimaging studies have characterized the pathophysiology of late-life depression (LLD) as a dysfunction of the brain networks involved in the regulation of emotion, motivational behavior, cognitive control, executive function, and self-referential thinking. In this article, we reviewed LLD-associated structural neuroimaging markers such as white matter hyperintensity (WMH), white matter integrity measured by diffusion tensor imaging, cortical and subcortical volumes, and cortical thickness, which may provide a structural basis for brain network dysfunction in LLD. LLD was associated with greater severity or volumes of deep, periventricular, or overall WMH and with decreased white matter integrity in the brain regions belonging to the fronto-striatal-limbic circuits and reduced white matter tract integrity which connects these circuits, such as the cingulum, corpus callosum, or uncinate fasciculus. Decreased volumes or cortical thickness in the prefrontal cortex, orbitofrontal cortex, anterior and posterior cingulate cortex, several temporal and parietal regions, hippocampus, amygdala, striatum, thalamus, and the insula were associated with LLD. These structural neuroimaging findings were also associated with cognitive dysfunction, which is a prominent clinical feature in LLD. Several structural neuroimaging markers including the WMH burden, white matter integrity, and cortical and subcortical volumes predicted antidepressant response in LLD. These structural neuroimaging findings support the hypothesis that disruption of the brain networks involved in emotion regulation and cognitive processing by impaired structural connectivity is strongly associated with the pathophysiology of LLD.

Common and Distinct Alterations of Cognitive Function and Brain Structure in Schizophrenia and Major Depressive Disorder: A Pilot Study

Objective: Numerous studies indicate that schizophrenia (SCZ) and major depressive disorder (MDD) share pathophysiological characteristics. Investigating the neurobiological features of psychiatric-affective disorders may facilitate the diagnosis of psychiatric disorders. Hence, we aimed to explore whether patients with SCZ and patients with MDD had the similar or distinct cognitive impairments and GMV alterations to further understand their underlying pathophysiological mechanisms. Methods: We recruited a total of 52 MDD patients, 64 SCZ patients, and 65 healthy controls (HCs). The Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery was used to assess cognitive functions. In addition, voxel-based morphometry (VBM) analysis was used to evaluate the gray matter volume (GMV) by using MRI scanning. One-way ANOVA and post-hoc tests were used to find the differences among the MDD, SCZ, and HCs. Finally, we explored the correlation between structural alterations and cognitive functions. Results: Compared with that of HCs, processing speed was impaired in both patients with SCZ and patients with MDD (F = 49.505, p < 0.001). SCZ patients displayed impaired cognitive performance in all dimensions of cognitive functions compared with HCs (p < 0.001, except social cognition, p = 0.043, Bonferroni corrected). Whole-brain VBM analysis showed that both SCZ and MDD groups had reductions of GMV in the medial superior frontal cortex (cluster-level FWE p < 0.05). Patients with SCZ exhibited declining GMV in the anterior cingulate cortex and right middle frontal cortex (MFC) compared with HCs and MDD patients (cluster-level FWE p < 0.05). The mean values of GMV in the right MFC had a positive correlation with the attention/vigilance function in patients with MDD (p = 0.014, partial. r = 0.349, without Bonferroni correction). Conclusions: In total, our study found that MDD and SCZ groups had common cognitive impairments and brain structural alterations, but the SCZ group exhibited more severe impairment than the MDD group in both fields. The above findings may provide a potential support for recognizing the convergent and divergent brain neural pathophysiological mechanisms between MDD and SCZ.

Neuroimaging Insight Into Fragile X-Associated Neuropsychiatric Disorders: Literature Review

FMR1 premutation is defined by 55-200 CGG repeats in the Fragile X Mental Retardation 1 (FMR1) gene. FMR1 premutation carriers are at risk of developing a neurodegenerative disease called fragile X-associated tremor/ataxia syndrome (FXTAS) and Fragile X-associated primary ovarian insufficiency (FXPOI) in adulthood. In the last years an increasingly board spectrum of clinical manifestations including psychiatric disorders have been described as occurring at a greater frequency among FMR1 premutation carriers. Herein, we reviewed the neuroimaging findings reported in relation with psychiatric symptomatology in adult FMR1 premutation carriers. A structured electronic literature search was conducted on FMR1 premutation and neuroimaging yielding a total of 3,229 articles examined. Of these, 7 articles were analyzed and are included in this review. The results showed that the main radiological findings among adult FMR1 premutation carriers presenting neuropsychiatric disorders were found on the amygdala and hippocampus, being the functional abnormalities more consistent and the volumetric changes more inconsistent among studies. From a molecular perspective, CGG repeat size, FMR1 mRNA and FMRP levels have been investigated in relation with the neuroimaging findings. Based on the published results, FMRP might play a key role in the pathophysiology of the psychiatric symptoms described among FMR1 premutation carriers. However, additional studies including further probes of brain function and a broader scope of psychiatric symptom measurement are required in order to obtain a comprehensive landscape of the neuropsychiatric phenotype associated with the FMR1 premutation.

Exposure to fine particulate matter and temporal dynamics of episodic memory and depressive symptoms in older women

BACKGROUND

Emerging data suggests PM2.5 (particulate matter with aerodynamic diameter <2.5 μm) may be associated with both earlier declines in episodic memory (EM) and increased depressive symptoms in older adults. Although late-life depressive symptoms are associated with EM, no longitudinal studies have examined the inter-relationship among PM2.5, depressive symptoms and EM.

METHODS

Older women (n = 2,202; aged 67-83 in 1999) enrolled in the Women's Health Initiative Study of Cognitive Aging completed up to eight annual assessments of depressive symptoms (15-item Geriatric Depression Scale) and EM (California Verbal Learning Test). A nationwide spatiotemporal model (1999-2010) was used to estimate ambient PM2.5 exposure at residential locations. Univariate and bivariate structural equation models (SEMs) for latent-change scores were used to examine how 3-year average PM2.5 preceding each assessment affects the temporal dynamics and bidirectional relations of annual changes in depressive symptoms and EM.

RESULTS

In univariate SEMs, one inter-quartile (4.04 μg/m3) increment of 3-year PM2.5 was significantly (p < 0.05) associated with accelerated declines in verbal learning (List A trials 1-3: β = -1.48) and free-recall memory (short-delay: β = -1.43; long-delay: β = -1.11), but not with change in depressive symptoms (β = 0.12; p = 0.71). In bivariate SEMs, significant associations were observed between PM2.5 and accelerated declines in EM measures (β = -1.44 to -0.99; p < 0.05) and between EM performance and changes in depressive symptoms (β = -0.08 to -0.05; p < 0.05), with significant indirect PM2.5 effects on changes in depressive symptoms (β = 0.08-0.10; p < 0.05). These findings were robust with adjustment for multiple demographic, lifestyle, and clinical factors, and remained after excluding subjects with dementia or mild cognitive impairment. No associations were found between PM2.5 and change in depressive symptoms or depressive symptoms and subsequent EM decline.

CONCLUSIONS

Findings suggest that PM2.5 neurotoxicity may damage brain areas implicated in EM, followed by manifestation of depressive symptoms. Our data did not support depressive symptoms as the neuropsychological mediator of accelerated brain aging associated with PM2.5 exposure.

The effect of hormone replacement therapy on cognitive function in postmenopausal women: An RCT

Background

During the reproductive age, the human brain becomes a target for gonadal steroid hormones. Estrogens influence neural function through effects on neurons and affects indirectly the oxidative stress, inflammation, the cerebral vascular and the immune system.

Objective

To evaluate the effect of the traditional hormone replacement therapy (HRT) on the cognitive function in postmenopausal women.

Materials and Methods

In this randomized clinical trial, 140 postmenopausal women, from November 2014 to February 2015, were included. Women were randomly divided into two groups. Each woman in the case group took traditional HRT (0.625mg conjugated equine estrogens+2.5mg medroxyprogesterone acetate daily) plus one Cal+D tablet (500 mg calcium+200 IU vitamin D) daily for four months. Women in the control group received only one Cal+D tablet (500 mg calcium+200 IU vitamin D) daily for four months period. The Montreal Cognitive Assessment (MoCA) and Green Climacteric Scale (GCS) questionnaires filled out after the intervention and compared between the two groups.

Results

The mean points of the MoCA after the intervention indicate that all MoCA domains except for the orientation improved in the case group. There was a significant difference in the memory domain after the treatment between the two groups. MoCA domains and GCS were negatively correlated after the intervention (r=-0.235,p=0.006).

Conclusion

The HRT has affected some of the MoCA factors. The effects of HRT on cognitive function should be studied in a large prospective study in a group of women in their early and late menopausal ages with periodic assessment of their cognitive function during these follow-up years.

Understanding the impact of sex and gender in Alzheimer's disease: A call to action

INTRODUCTION

Precision medicine methodologies and approaches have advanced our understanding of the clinical presentation, development, progression, and management of Alzheimer's disease (AD) dementia. However, sex and gender have not yet been adequately integrated into many of these approaches.

METHODS

The Society for Women's Health Research Interdisciplinary Network on AD, comprised of an expert panel of scientists and clinicians, reviewed ongoing and published research related to sex and gender differences in AD.

RESULTS

The current review is a result of this Network's efforts and aims to: (1) highlight the current state-of-the-science in the AD field on sex and gender differences; (2) address knowledge gaps in assessing sex and gender differences; and (3) discuss 12 priority areas that merit further research.

DISCUSSION

The exclusion of sex and gender has impeded faster advancement in the detection, treatment, and care of AD across the clinical spectrum. Greater attention to these differences will improve outcomes for both sexes.

Common and distinct abnormal frontal-limbic system structural and functional patterns in patients with major depression and bipolar disorder

Major depressive disorder (MDD) and bipolar disorder (BD) are common severe affective diseases. Although previous neuroimaging studies have investigated brain abnormalities in MDD or BD, the structural and functional differences between these two disorders remain unclear. In this study, we adopted a multimodal approach, combining voxel-based morphometry (VBM) and functional connectivity (FC), to study the common and distinct structural and functional alterations in unmedicated MDD and BD patients. The VBM analysis revealed that both the MDD and BD patients showed decreased gray matter volume (GMV) in the left anterior cingulate cortex (ACC_L) and right hippocampus (HIP_R) compared with the healthy controls, and the MDD patients showed decreased GMV in the left superior frontal gyrus (SFG_L) and ACC_L compared with the BD patients. Furthermore, we took these clusters as seed regions to analyze the abnormal resting-state functional connectivity (RSFC) in the patients. We found that both the MDD and BD groups had decreased RSFC between the ACC_L and the left orbitofrontal cortex (OFC_L) and that the MDD group had decreased RSFC between the SFG_L and the HIP_L, compared with the healthy controls. Our results revealed that the MDD and BD patients were more similar than different in GMV and RSFC. These findings indicate that investigating the frontal-limbic system could be useful for understanding the underlying mechanisms of these two disorders.

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Both MDD and BD patients had reduced GMV in the ACC_L and HIP_R compared with HC.

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MDD patients had decreased GMV in the ACC_L and SFG_L compared with BD patients.

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Both BD and MDD patients had decreased ACC-OFC RSFC compared with HC.

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The MDD and BD patients were more similar than different in GMV and RSFC.

Depressive Symptom Dimensions and Their Association with Hippocampal and Entorhinal Cortex Volumes in Community Dwelling Older Adults

Objective: Research has shown that depression is a risk factor for Alzheimer’s disease (AD) and subsequent cognitive decline. This is compounded by evidence showing an association between depression and reduced hippocampal volumes; a primary structure implicated in the pathogenesis of the disease. Less is known about the relationship between depression and other AD vulnerable regions such as the entorhinal cortex. Given the heterogeneity of depressive symptom presentation, we examined whether symptom dimensions were associated with hippocampal and entorhinal cortex volumes in community dwelling older adults.

Methods: Eighty-one community dwelling adults completed the Beck Depression Inventory – second edition and underwent structural neuroimaging. Measures of hippocampal and entorhinal cortex volumes were obtained using FreeSurfer software. Linear regression models included regions of interest as dependent variables, with depressive symptom dimensions, as independent variables, controlling for total intracranial volumes, age, education, and gender.

Results: Somatic symptoms were negatively associated with total, right, and left hippocampal volumes. Affective symptoms were negatively associated with total entorhinal cortex volumes, with a marginal main effect on left entorhinal cortex volumes.

Conclusion: Our findings provide support for examining depressive symptoms and their association with AD vulnerable regions along subdimensions of affective, cognitive, and somatic symptoms to better understand profiles of symptoms most associated with these regions. Conceptualizing depressive symptoms in this way may also better inform treatment approaches in terms of targeting types of symptoms that may be more closely linked to poorer brain and cognitive health outcomes.

Mild cognitive impairment in type 2 diabetes mellitus and related risk factors: a review

Type 2 diabetes mellitus (T2DM) is a global epidemic disease and has become a significant health problem. Many studies have raised concern about the mild cognitive impairment (MCI) with T2DM and even the Alzheimer’s disease patients with T2DM. The incidence of MCI is higher in individuals with T2DM than those without diabetes. Cognitive changes might affect everyday activities depending on the work and situation. Although the exact pathophysiology of MCI in T2DM is unclear, many studies suggest that the alterations in pathoglycemia, diabetic complications, related end products, and physical/psychological status are significant risk factors. In this article, we systematically overview the studies to illustrate the related risk factors of cognitive impairment in patients with T2DM. Further high quality studies and treatment need to be initiated and it will become incumbent on clinicians to identify and cure the earliest signs of clinical impairment.

Late-Life Depression, Hippocampal Volumes, and Hypothalamic-Pituitary-Adrenal Axis Regulation: A Systematic Review and Meta-analysis

BACKGROUND

We systematically reviewed and meta-analyzed the association of late-life depression (LLD) with hippocampal volume (HCV) and total brain volume (TBV), and of cortisol levels with HCV, including subgroup analyses of depression characteristics and methodological aspects.

METHODS

We searched PubMed and Embase for original studies that examined the cross-sectional relationship between LLD and HCV or TBV, and 46 studies fulfilled the inclusion criteria. Standardized mean differences (Hedges' g) between LLD and control subjects were calculated from crude or adjusted brain volumes using random effects. Standardized Fisher transformations of the correlations between cortisol levels and HCVs were calculated using random effects.

RESULTS

We included 2702 LLD patients and 11,165 control subjects from 35 studies examining HCV. Relative to control subjects, patients had significantly smaller HCVs (standardized mean difference = -0.32 [95% confidence interval, -0.44 to -0.19]). Subgroup analyses showed that late-onset depression was more strongly associated with HCV than early-onset depression. In addition, effect sizes were larger for case-control studies, studies with lower quality, and studies with small sample size, and were almost absent in cohort studies and studies with larger sample sizes. For TBV, 2523 patients and 7880 control subjects from 31 studies were included. The standardized mean difference in TBV between LLD and control subjects was -0.10 (95% confidence interval, -0.16 to -0.04). Of the 12 studies included, higher levels of cortisol were associated with smaller HCV (correlation = -0.11 [95% confidence interval, -0.18 to -0.04]).

CONCLUSIONS

While an overall measure of LLD may be associated with smaller HCVs, differentiating clinical aspects of LLD and examining methodological issues show that this relationship is not straightforward.

Serum lipid changes following the onset of depressive symptoms in postmenopausal women

A cross-sectional association between depression and serum low-density lipoprotein cholesterol (LDL-c) has been noted in psychiatric literature, raising the question of temporality: does low LDL-c predict depression, does depression lead to changes in LDL-c levels, or is this relationship bidirectional? In a previous longitudinal analysis of postmenopausal women ages 50-79 who participated in the Women's Health Initiative (WHI), we detected an association between low LDL-c and the subsequent onset of depressive symptoms (HR=1.25, 95% CI 1.05-1.49, p=0.01). This current study uses the WHI cohort to explore the question of temporality in the opposite direction, examining the influence of depressive symptoms on subsequent changes in LDL-c levels. This study provides no evidence to suggest an association between depression and subsequent changes in LDL-c level (-2.78mg/dL, 95% CI=-7.49 to 1.92, p=0.25), nor was any association detected for total cholesterol, HDL, or triglyceride changes over time. Further, this study demonstrates that the relationship between depression and serum LDL changes is not mediated by changes in weight, exercise, or energy intake.

Prolonged ovarian hormone deprivation alters the effects of 17β-estradiol on microRNA expression in the aged female rat hypothalamus

Administration of 17β-estradiol (E₂) has beneficial effects on cognitive function in peri- but not post-menopausal women, yet the molecular mechanisms underlying age-related changes in E₂ action remain unclear. We propose that there is a biological switch in E₂ action that occurs coincident with age and length of time after ovarian hormone depletion, and we hypothesized that age-dependent regulation of microRNAs (miRNAs) could be the molecular basis for that switch. Previously we showed that miRNAs are regulated by E₂ in young compared to aged female rats. Here we tested whether increasing lengths of ovarian hormone deprivation in aged females altered E₂ regulation of these mature miRNAs. In addition, we determined where along the miRNA biogenesis pathway E₂ exerted its effects. Our results showed that age and increased lengths of ovarian hormone deprivation abolished the ability of E₂ to regulate mature miRNA expression in the brain. Further, we show that E₂ acted at specific points along the miRNA biogenesis pathway.

Effects of Hormone Therapy on Brain Volumes Changes of Postmenopausal Women Revealed by Optimally-Discriminative Voxel-Based Morphometry

Backgrounds

The Women's Health Initiative Memory Study Magnetic Resonance Imaging (WHIMS-MRI) provides an opportunity to evaluate how menopausal hormone therapy (HT) affects the structure of older women’s brains. Our earlier work based on region of interest (ROI) analysis demonstrated potential structural changes underlying adverse effects of HT on cognition. However, the ROI-based analysis is limited in statistical power and precision, and cannot provide fine-grained mapping of whole-brain changes.

Methods

We aimed to identify local structural differences between HT and placebo groups from WHIMS-MRI in a whole-brain refined level, by using a novel method, named Optimally-Discriminative Voxel-Based Analysis (ODVBA). ODVBA is a recently proposed imaging pattern analysis approach for group comparisons utilizing a spatially adaptive analysis scheme to accurately locate areas of group differences, thereby providing superior sensitivity and specificity to detect the structural brain changes over conventional methods.

Results

Women assigned to HT treatments had significant Gray Matter (GM) losses compared to the placebo groups in the anterior cingulate and the adjacent medial frontal gyrus, and the orbitofrontal cortex, which persisted after multiple comparison corrections. There were no regions where HT was significantly associated with larger volumes compared to placebo, although a trend of marginal significance was found in the posterior cingulate cortical area. The CEE-Alone and CEE+MPA groups, although compared with different placebo controls, demonstrated similar effects according to the spatial patterns of structural changes.

Conclusions

HT had adverse effects on GM volumes and risk for cognitive impairment and dementia in older women. These findings advanced our understanding of the neurobiological underpinnings of HT effects.

Longitudinal study of low serum LDL cholesterol and depressive symptom onset in postmenopause

OBJECTIVE

The aim of this study was to characterize the relationship between serum low-density lipoprotein cholesterol (LDL-c) and subsequent depressive symptoms onset in postmenopausal women. We secondarily assessed serum high-density lipoprotein (HDL-c), total cholesterol, and triglycerides.

METHOD

This population-based prospective cohort study utilizes data from 24,216 women between 50 and 79 years of age who were participants of the Women's Health Initiative, which originally ran from 1993 to 2005 and has since incorporated 2 extension studies, with the most recent culminating in 2015. Fasting lipids were measured for all participants at baseline and for a subset through 6 years of follow-up. Depressive symptoms were characterized using the Burnam 8-item scale for depressive disorders (Center for Epidemiologic Studies-Depression/Diagnostic Interview Schedule short form) at baseline and during follow-up, using a cut point of 0.06 to indicate presence of depressive symptoms.

RESULTS

The lowest quintile of LDL-c was associated with an increased risk of subsequent depressive symptoms (hazard ratio [HR] = 1.25, 95% CI = 1.05-1.49, P = .01), and follow-up analyses demonstrated that the elevated risk appeared to be confined to the lowest decile (LDL-c < 100 mg/dL). Further, this elevated risk was moderated by lipid-lowering drug treatment. Elevated risk was demonstrated among those who reported no lipid-lowering medication use (HR = 1.23, 95% CI = 1.03-1.47, P = .02), but not among those reporting use (HR = 0.65, 95% CI = 0.18-2.29, P = .50).

CONCLUSIONS

Among postmenopausal women, untreated serum LDL-c below 100 mg/dL was associated with an increased risk of developing depressive symptoms. No excess risk was observed in those attaining LDL-c < 100 mg/dL with lipid-lowering therapy. These findings have important implications for risk assessment, treatment considerations, and mechanistic insight.

Brain hyperintensity location determines outcome in the triad of impaired cognition, physical health and depressive symptoms: A cohort study in late life

PURPOSE OF THE STUDY

Brain hyperintensities, detectable with MRI, increase with age. They are associated with a triad of impairment in cognitive ability, depression and physical health. Here we test the hypothesis that the association between hyperintensities and cognitive ability, physical health and depressive symptoms depends on lesion location.

DESIGN AND METHODS

244 members of the Aberdeen 1936 Birth Cohort were recruited to this study. 227 participants completed brain MRI and their hyperintensities were scored using Scheltens's scale. 205 had complete imaging, cognitive, physical health and depressive symptom score data. The relationships between hyperintensity location and depressive symptoms, cognitive ability and physical health were examined by correlation and structural equation analysis.

RESULTS

We found that depressive symptoms correlated with hyperintensity burden in the grey matter (r=0.14, p=0.04) and infratentorial regions (r=0.17, p=0.01). Infratentorial hyperintensities correlated with reduced peak expiratory flow rate (r=-0.26, p<0.001) and impaired gait (r=0.13, p=0.05). No relationship was found between white matter and periventricular (supratentoral) hyperintensities and depressive symptoms. Hyperintensities in the supratentorial and infratentorial regions were associated with reduced cognitive performance. Using structural equation modelling we found that the association between hyperintensities and depressive symptoms was mediated by negative effects on physical health and cognitive ability.

CONCLUSIONS

Hyperintensities in deep brain structures are associated with depressive symptoms, mediated via impaired physical health and cognitive ability. Participants with higher cognitive ability and better physical health are at lower risk of depressive symptoms.

Depression, depressive symptoms, and rate of hippocampal atrophy in a longitudinal cohort of older men and women

BACKGROUND

Several studies have reported smaller hippocampal volume (HcV) in depression patients; however, the temporality of the association remains unknown. One proposed hypothesis is that depression may cause HcV loss. This study evaluates whether previous depression and recent depressive symptoms are associated with HcV and HcV loss.

METHOD

We used a prospective cohort of older adults (n = 1328; age = 65-80 years) with two cerebral magnetic resonance imaging examinations at baseline and 4-year follow-up. Using multivariable linear regression models, we estimated, in stratified analyses by gender, the association between indicators of history of depression and its severity (age at onset, recurrence, hospitalization for depression), proximal depressive symptoms [Center for Epidemiologic Studies-Depression (CES-D) scale], baseline antidepressant use, and the outcomes: baseline HcV and annual percentage change in HcV.

RESULTS

At baseline, women with more depressive symptoms had smaller HcV [-0.05 cm3, 95% confidence interval (CI) -0.1 to -0.01 cm3 per 10-unit increase in CES-D scores]. History of depression was associated with a 0.2% faster annual HcV loss in women (95% CI 0.01-0.36%). More baseline depressive symptoms and worsening of these symptoms were also associated with accelerated HcV loss in women. No associations were observed in men. Treatment for depression was associated with slower HcV loss in women and men.

CONCLUSIONS

While only concomitant depressive symptoms were associated with HcV, both previous depression and more proximal depressive symptoms were associated with faster HcV loss in women.

Plasma galanin is a biomarker for severity of major depressive disorder

OBJECTIVE

This study investigated the association between plasma galanin level and depression severity.

METHODS

The severity of depression symptoms of 79 patients with major depressive disorder (MDD; 52 women and 27 men, 71 patients in onset, 8 in remission) was assessed using the 17-item Hamilton Depression Rating Scale. Venous fasting blood samples (5 mL) were taken from the 79 MDD patients, 35 healthy siblings, and 19 healthy controls, and plasma samples were prepared. Galanin levels in the plasma were measured by radioimmunoassay.

RESULTS

Plasma galanin in MDD patients was significantly higher than that of remission patients, healthy siblings, or healthy controls (P < 0.05) There was no significant difference between the healthy sibling and healthy control groups (P = 0.924). Plasma galanin of remission patients was also significantly higher than that of healthy controls (P < 0.05). There was no significant correlation between age and galanin levels in the 79 patients (r = 0.053, P = 0.646), nor was there a correlation between age and galanin levels when patients were stratified by gender (P > 0.05). There was a significant positive correlation between plasma galanin levels and depression severity in women MDD patients (r = 0.329, df = 42, P = 0.020), but not in men patients.

CONCLUSIONS

Plasma galanin levels may be an important biomarker for depression severity, especially in female patients.

Comparison of brain structural variables, neuropsychological factors, and treatment outcome in early-onset versus late-onset late-life depression

OBJECTIVE

To compare differences in gray matter volumes, white matter and subcortical gray matter hyperintensities, neuropsychological factors, and treatment outcome between early- and late-onset late-life depressed (LLD) subjects.

METHODS

We conducted a prospective, nonrandomized, controlled trial at the outpatient clinics at Washington University and Duke University on 126 subjects, aged 60 years or older, who met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria for major depression, scored 20 or more on the Montgomery-Asberg Depression Rating Scale (MADRS), and received neuropsychological testing and magnetic resonance imaging. Subjects were excluded for cognitive impairment or severe medical disorders. After 12 weeks of sertraline treatment, subjects' MADRS scores over time and neuropsychological factors were studied.

RESULTS

Left anterior cingulate thickness was significantly smaller in the late-onset depressed group than in the early-onset LLD subjects. The late-onset group also had more hyperintensities than the early-onset LLD subjects. No differences were found in neuropsychological factor scores or treatment outcome between early-onset and late-onset LLD subjects.

CONCLUSION

Age at onset of depressive symptoms in LLD subjects are associated with differences in cortical thickness and white matter and subcortical gray matter hyperintensities, but age at onset did not affect neuropsychological factors or treatment outcome.

Hippocampal atrophy and subsequent depressive symptoms in older men and women: results from a 10-year prospective cohort

Several studies have reported smaller hippocampal volume in patients with depression. However, the temporality of the association is undetermined. One hypothesis is that hippocampal atrophy might be a susceptibility factor for depression. In the present study, we assessed whether hippocampal atrophy was associated with subsequent depressive symptoms in a cohort of older French adults (n = 1,309) who were 65-80 years of age and enrolled into the study in 1999-2001 in Dijon, France. Subjects were followed for more than 10 years. Participants underwent 2 cerebral magnetic resonance imaging scans, one at baseline and one at the 4-year follow-up. We used linear mixed models to estimate the associations of hippocampal atrophy with 1) the average depressive symptom scores over follow-up (using the Center for Epidemiologic Studies-Depression scale) measured biennially over the subsequent 6 years and 2) changes in symptom scores over follow-up. In women, a 2-standard-deviation increase in annual hippocampal atrophy was associated with a 1.67-point (95% confidence interval: 0.59, 2.77) increase in the average depressive symptom score over follow-up and with a 1.97-point (95% confidence interval: 0.68, 3.24) increase in scores over the 2 subsequent years but not with later changes in symptoms. No association was detected in men. Accounting for potential selective attrition (using inverse probability weights) did not alter results. Hippocampal atrophy was associated with more subsequent depressive symptoms and with shorter-term worsening of symptoms in women.

Frontal-insula gray matter deficits in first-episode medication-naïve patients with major depressive disorder

OBJECTIVE

This study is designed to investigate the gray matter volume (GMV) deficits in patients with first-episode medication-naïve major depressive disorder (MDD).

METHODS

We enrolled 38 patients with first-episode medication-naïve MDD and 27 controls in this project. Voxel-based morphometry was used to compare GMV differences between two groups. Besides, the relationship between GMV of patients and the severity of clinical symptoms was estimated to confirm the role of GMV deficits in clinical symptoms. The correlation between total GMV and illness duration was also performed to elucidate the impacts of untreated duration on the GMV.

RESULTS

We found that first-episode medication-naïve MDD patients had significant GMV deficits in bilateral superior frontal gyri, left middle frontal gyrus, left medial frontal gyrus and left insula. The GMV of patient group was negatively correlated with the severity of clinical symptoms and the illness duration.

CONCLUSION

A pattern of GMV deficits in fronto-insula might represent the biomarker for first-episode medication-naïve MDD.

Extreme deep white matter hyperintensity volumes are associated with African American race

BACKGROUND

African Americans (AAs) have a higher prevalence of extreme ischemic white matter hyperintensities (WMHs) on magnetic resonance imaging (MRI) than do European Americans (EAs) based on the Cardiovascular Health Study (CHS) score. Ischemic white matter disease, limited to the deep white matter, may be biologically distinct from disease in other regions and may reflect a previously observed trend toward an increased risk of subcortical lacunar infarcts in AAs. We hypothesized that extreme deep WMH volume (DWMV) or periventricular volume (PV) may also have a higher prevalence in AAs. Thus, we studied extreme CHS scores and extreme DWMV and PV in a healthy population enriched for cardiovascular disease risk factors.

METHODS

We imaged the brains of 593 subjects who were first-degree relatives of probands with early onset coronary disease prior to 60 years of age. WMHs were manually delineated on 3-tesla cranial MRI by a trained radiology reader; the location and volume of lesions were characterized using automated software. DWMV and PV were measured directly with automated software, and the CHS score was determined by a neuroradiologist. Volumes were characterized as being in the upper 25% versus lower 75% of total lesion volume. Volumes in the upper versus the remaining quartiles were examined for AA versus EA race using multiple logistic regression (generalized estimating equations adjusted for family relatedness) and adjusted for major vascular disease risk factors including age ≥55 years versus <55, sex, current smoking, obesity, hypertension, diabetes and low-density lipoprotein >160 mg/dl.

RESULTS

Participants were 58% women and 37% AAs, with a mean age of 51.5 ± 11.0 years (range, 29-74 years). AAs had significantly higher odds of having extreme DWMVs (odds ratio, OR, 1.8; 95% confidence interval, CI, 1.2-2.9; p = 0.0076) independently of age, sex, hypertension and all other risk factors. AAs also had significantly higher odds of having extreme CHS scores ≥3 (OR, 1.3; 95% CI, 1.1-3.6; p = 0.025). Extreme PV was not significantly associated with AA race (OR, 1.3; 95% CI, 0.81-2.1; p = 0.26).

CONCLUSIONS

AAs from families with early-onset cardiovascular disease are more likely to have extreme DWMVs (a subclinical form of cerebrovascular disease) and an extreme CHS score, but not extreme PV, independently of age and other cardiovascular disease risk factors. These findings suggest that this AA population is at an increased risk for DWMV and may be at an increased risk for future subcortical stroke. Longitudinal studies are required to see if DWMV is predictive of symptomatic subcortical strokes in this population.

Dysthymic disorder in the elderly population

The diagnosis of dysthymic disorder was created in DSM-III and maintained in DSM-IV to describe a depressive syndrome of mild to moderate severity of at least two years' duration that did not meet criteria for major depressive disorder. The prevalence of dysthymic disorder is approximately 2% in the elderly population where subsyndromal depressions of lesser severity are more common. Dysthymic disorder was replaced in DSM-V by the diagnosis of "persistent depressive disorder" that includes chronic major depression and dysthymic disorder. In older adults, epidemiological and clinical evidence supports the use of the term "dysthymic disorder." In contrast to young adults with dysthymic disorder, older adults with dysthymic disorder commonly present with late age of onset, without major depression and other psychiatric disorders, and with a low rate of family history of mood disorders. They often have stressors such as loss of social support and bereavement, and some have cerebrovascular or neurodegenerative pathology. A minority has chronic depression dating from youth with psychiatric comorbidity similar to young adults with dysthymic disorder. In older adults, both dysthymic disorder and subsyndromal depression increase disability and lead to poor medical outcomes. Elderly patients with dysthymic disorder are seen mainly in primary care where identification and treatment are often inadequate. Treatment with antidepressant medication shows marginal superiority over placebo in controlled trials, and problem-solving therapy shows similar efficacy. Combined treatment and collaborative care models show slightly better results, but cost effectiveness is a concern. Further work is needed to clarify optimal approaches to the treatment of dysthymic disorder in elderly patients.

The default mode network may be the key substrate of depressive symptom-related cognitive changes

Depressive symptoms are associated with an increased risk of Alzheimer's disease (AD) but the mechanism(s) involved has not been well established. In a convenience sample of participants in the University of Kansas' Brain Aging Project, we use structural equation modeling (SEM) to explicitly distinguish depressive symptom-related variance in cognitive task performance (i.e., DEPCOG) from that which is unrelated to a depressive symptoms. DEPCOG is strongly associated with the cognitive correlates of functional status (δ), which we previously associated with elements of the Default Mode Network (DMN). Both δ and DEPCOG map to a posterior cingulate seeded network that has recently been associated with amyloid-β deposition and includes elements of the DMN. Both contribute significantly to clinical dementia status and dementia severity, as measured by the Clinical Dementia Rating Scale Sum of Boxes. These findings suggest that the cognitive correlates of depressive symptoms, even in the absence of a major depressive episode, may contribute to dementia in their own right, and could be responsible for some cases of incident clinical "AD". This conclusion suggests new opportunities for the latter's diagnosis, prevention, and treatment.

Hippocampal correlates of depression in healthy elderly adults

Mixed findings have been reported on the relationship between hippocampal integrity and major depression in clinical populations. Few neuroimaging studies have investigated associations between hippocampal measures and depressive symptoms in nondemented older adults. Here, we address this issue by imaging 36 nondemented adults over age 70 from the Einstein Aging Study, a community-based sample from the Bronx, NY. Depressive symptoms were assessed using the 15-item Geriatric Depression scale (GDS). Clinically significant depression was defined using a cut-off score of 5 or greater. Hippocampal data included MRI-derived volume data normalized to midsagittal area and MRS-derived N-acetylaspartate to creatine ratios (NAA/Cr). Our result indicates that smaller total hippocampal volume was associated with higher GDS scores, but there were no significant association between hippocampal NAA/Cr and GDS score. These effects were consistent after controlling for age, education, and gender. Reduction in hippocampal volume could represent a risk factor or a consequence of depression in older adults. Further studies are needed to better understand the role of the hippocampus in the development and experience of depression in older adults.

Recent advances in neuroimaging biomarkers in geriatric psychiatry

Neuroimaging, both structural and functional, serve as useful adjuncts to clinical assessment, and can provide objective, reliable means of assessing disease presence and process in the aging population. In the following review we briefly explain current imaging methodologies. Then, we analyze recent developments in developing neuroimaging biomarkers for two highly prevalent disorders in the elderly population- Alzheimer's disease (AD) and late-life depression (LLD). In AD, efforts are focused on early diagnosis through in vivo visualization of disease pathophysiology. In LLD, recent imaging evidence supports the role of white matter ischemic changes in the pathogenesis of depression in the elderly, the "vascular hypothesis." Finally, we discuss potential roles for neuroimaging biomarkers in geriatric psychiatry in the future.

Alzheimer's disease pathology does not mediate the association between depressive symptoms and subsequent cognitive decline

BACKGROUND

Depressive symptoms in nondemented individuals appear to hasten the progression from mild cognitive impairment to clinical Alzheimer's disease (AD) and double the risk of incident AD. However, the mechanism(s) by which depression might affect this risk has not been well established. The purpose of this analysis was to test the hypothesis that AD pathology mediates depression's apparent effect on the risk of dementia conversion using longitudinally collected psychometric testing and autopsy data from the Honolulu-Asia Aging Study.

METHODS

Latent factor variables representing AD, cortical Lewy body (CLB), and ischemic neuropathology were tested as potential mediators of the association between the Center for Epidemiological Studies depression scale (CES-D) score and the 10-year prospective rate of cognitive decline, adjusted for baseline cognition, age, education, total number of medications, and brain weight at autopsy.

RESULTS

CES-D scores, neurofibrillary tangle counts, CLB counts, and ischemic lesions each made significant independent contributions to cognitive decline. However, CES-D scores were not significantly associated with any pathological variable; thus the pathological variables were not mediators of the effect of CES-D scores on cognitive decline.

CONCLUSIONS

Subsyndromal depressive symptoms are significantly associated with subsequent cognitive decline. Although the effect is relatively modest, it is stronger than that of amyloid-related neuropathologies and independent of that of neurofibrillary tangles, cortical Lewy bodies, and ischemic lesions. Our results argue against the role of AD-related neuropathology as a mediator of depression's effect on cognitive decline, but cannot rule out a significant mediation effect in a subset of cases, perhaps with more severe baseline depressive symptoms.

Associations of current and remitted major depressive disorder with brain atrophy: the AGES-Reykjavik Study

BACKGROUND

To examine whether lifetime DSM-IV diagnosis of major depressive disorder (MDD), including age at onset and number of episodes, is associated with brain atrophy in older persons without dementia.

METHOD

Within the population-based Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study, 4354 persons (mean age 76 ± 5 years, 58% women) without dementia had a 1.5-T brain magnetic resonance imaging (MRI) scan. Automated brain segmentation total and regional brain volumes were calculated. History of MDD, including age at onset and number of episodes, and MDD in the past 2 weeks was diagnosed according to DSM-IV criteria using the Mini-International Neuropsychiatric Interview (MINI).

RESULTS

Of the total sample, 4.5% reported a lifetime history of MDD; 1.5% had a current diagnosis of MDD (including 75% with a prior history of depression) and 3.0% had a past but no current diagnosis (remission). After adjusting for multiple covariates, compared to participants never depressed, those with current MDD (irrespective of past) had more global brain atrophy [B = -1.25%, 95% confidence interval (CI) -2.05 to -0.44], including more gray- and white-matter atrophy in most lobes, and also more atrophy of the hippocampus and thalamus. Participants with current, first-onset MDD also had more brain atrophy (B = -1.62%, 95% CI -3.30 to 0.05) whereas those remitted did not (B = 0.06%, 95% CI -0.54 to 0.66).

CONCLUSIONS

In older persons without dementia, current MDD, irrespective of prior history, but not remitted MDD was associated with widespread gray- and white-matter brain atrophy. Prospective studies should examine whether MDD is a consequence of, or contributes to, brain volume loss and development of dementia.

Depressive symptoms in late life and cerebrovascular disease: the importance of intelligence and lesion location

BACKGROUND

The influence of white matter lesions on depressive symptoms in healthy ageing populations remains unclear. In this study, we examined the relationship between depressive symptoms and magnetic resonance imaging (MRI) detected cerebrovascular disease in a normal population living independently in the community, and measured the influence of location of brain abnormalities, fluid intelligence, living alone, and sex.

METHODS

Prospective cohort: 497 community dwelling individuals all born in 1936, who took part in the Scottish Mental Survey of 1947, were followed up in 2000 and at biannual intervals in a longitudinal study of health and cognitive aging. Two hundred forty-four volunteered for brain MRI in 2004-2006. Suitable data were available in 219/244, of whom 115 were men. Brain hyperintensities in lobar white matter, basal ganglia , periventricular, and infratentorial regions were measured using Scheltens' scale. Depressed mood was assessed using the Hospital Anxiety and Depression Scale (HADS) on three biannual intervals. Relationships between Scheltens' scores, HADS-D scores, fluid intelligence, living alone, and sex were assessed using general linear modeling.

RESULTS

The main predictor of depressive symptom scores was poorer fluid intelligence (partial η(2) =0.023-0.028, P < .05). Ischemic change in the brainstem (partial η(2) = 0.026, P ≤.05) and basal ganglia (partial η(2) =0.018, P ≤ .05) also predicted HADS-D scores. There was no relationship with sex or living alone.

CONCLUSIONS

Hyperintensities in the brainstem and basal ganglia are associated with depressive symptoms. Higher fluid intelligence is associated with lower depressive symptoms in this normal, ageing population.

The co-existence of geriatric depression and amnestic mild cognitive impairment detrimentally affect gray matter volumes: voxel-based morphometry study

While late-life depression (LLD) and amnestic mild cognitive impairment (aMCI), alone and in combination, is associated with an increased risk of incident Alzheimer's disease (AD), the neurobiological mechanisms of this link are unclear. We examined the main and interactive effects of LLD and aMCI on the gray matter (GM) volumes in 72 physically healthy participants aged 60 and older. Participants were separated into normal controls, cognitively normal depressed, non-depressed aMCI, and depressed aMCI groups. Optimized voxel-based morphometry estimated GM volumes. The main and interactive effects of LLD and aMCI, and of depressive symptoms and episodic memory deficits on the GM volumes were analyzed. While decreased GM volumes in the mood regulating circuitry structures were associated with depression, GM atrophy in regions essential for various cognitive performance were related to aMCI. LLD-aMCI interactions were associated with widespread subcortical and cortical GM volume loss of brain structures implicated in AD. The interactions between episodic memory deficits and depressive symptom severity are associated with volume loss in right inferior frontal gyrus/anterior insula and left medial frontal gyrus clusters. Our findings suggest that the co-existence of these clinical phenotypes is a potential marker for higher risk of AD.

Treatment course with antidepressant therapy in late-life depression

OBJECTIVE

In order to assess the effect of gray matter volumes and cortical thickness on antidepressant treatment response in late-life depression, the authors examined the relationship between brain regions identified a priori and Montgomery-Åsberg Depression Rating Scale (MADRS) scores over the course of an antidepressant treatment trial.

METHOD

In a nonrandomized prospective trial, 168 patients who were at least 60 years of age and met DSM-IV criteria for major depression underwent MRI and were enrolled in a 12-week treatment study. Exclusion criteria included cognitive impairment or severe medical disorders. The volumes or cortical thicknesses of regions of interest that differed between the depressed group and a comparison group (N=50) were determined. These regions of interest were used in analyses of the depressed group to predict antidepressant treatment outcome. Mixed-model analyses adjusting for age, education, age at depression onset, race, baseline MADRS score, scanner, and interaction with time examined predictors of MADRS scores over time.

RESULTS

Smaller hippocampal volumes predicted a slower response to treatment. With the inclusion of white matter hyper-intensity severity and neuropsychological factor scores, the best model included hippocampal volume and cognitive processing speed to predict rate of response over time. A secondary analysis showed that hippocampal volume and frontal pole thickness differed between patients who achieved remission and those who did not.

CONCLUSIONS

These data expand our understanding of the prediction of treatment course in late-life depression. The authors propose that the primary variables of hippocampal volume and cognitive processing speed, subsuming other contributing variables (episodic memory, executive function, language processing) predict antidepressant response.

Depressive symptoms, antidepressant use, and brain volumes on MRI in a population-based cohort of old persons without dementia

We examined whether late-life depression, including depressive symptoms and antidepressant use, was associated with smaller total brain volume, smaller hippocampal volume, and larger white matter hyperintensity (WMH) volume in a large community-based cohort of old persons without dementia. Within the Washington/Hamilton Height-Inwood Columbia Aging Project (WHICAP), a community-based cohort study in northern Manhattan, 630 persons without dementia (mean age 80 years, SD = 5) had volumetric measures of the total brain, hippocampus, and WMH at 1.5 Tesla MRI and data on current depression, defined as a score of 4 or higher on the 10-item Center for Epidemiologic Studies-Depression (CES-D) scale, or use of antidepressants. Multiple linear regression analyses adjusted for age, gender, ethnicity, education, cardiovascular disease history, and MRI parameters showed that subjects with current depression had smaller relative total brain volume (B = -0.86%; 95% CI -1.68 to -0.05%; p < 0.05), smaller relative hippocampal volume (B = -0.07 ml; 95% CI -0.14 to 0.00 ml; p = 0.05), and larger relative WMH volume (natural logtransformed B = 0.19 ml; 95% CI 0.02 to 0.35 ml; p < 0.05). When examined separately, antidepressant use was significantly associated with smaller total brain, smaller hippocampal, and larger WMH volume, while high CES-D scores were not significantly associated with any of the brain measures, although the direction of association was similar as for antidepressant use. With the caveat that analyses were cross-sectional and we had no formal diagnosis of depression, our findings suggest that in this community-based sample of old persons without dementia, late-life depression is associated with more brain atrophy and more white matter lesions, which was mainly driven by antidepressant use.

Biological basis of late life depression

Late life depression (LLD) is an important area of research given the growing elderly population. The purpose of this review is to examine the available evidence for the biological basis of LLD. Structural neuroimaging shows specific gray matter structural changes in LLD as well as ischemic lesion burden via white matter hyperintensities. Similarly, specific neuropsychological deficits have been found in LLD. An inflammatory response is another possible underlying contributor to the pathophysiology of LLD. We review the available literature examining these multiple facets of LLD and how each may affect clinical outcome in the depressed elderly.