White matter hyperintensities and their associations with suicidality in psychiatrically hospitalized children and adolescents

Modeling the development of cognitive reserve in children: A residual index approach

OBJECTIVE

To model cognitive reserve (CR) longitudinally in a neurodiverse pediatric sample using a residual index approach, and to test the criterion and construct validity of this index.

METHOD

Participants were N = 115 children aged 9.5-13 years at baseline (MAge = 10.48 years, SDAge = 0.61), and n = 43 (37.4%) met criteria for ADHD. The CR index represented variance in Matrix Reasoning scores from the WASI that was unexplained by MRI-based brain variables (bilateral hippocampal volumes, total gray matter volumes, and total white matter hypointensity volumes) or demographics (age and sex).

RESULTS

At baseline, the CR index predicted math computation ability (estimate = 0.50, SE = 0.07, p < .001), and word reading ability (estimate = 0.26, SE = 0.10, p = .012). Longitudinally, change in CR over time was not associated with change in math computation ability (estimate = -0.02, SE = 0.03, p < .513), but did predict change in word reading ability (estimate = 0.10, SE = 0.03, p < .001). Change in CR was also found to moderate the relationship between change in word reading ability and white matter hypointensity volume (estimate = 0.10, SE = 0.05, p = .045).

CONCLUSIONS

Evidence for the criterion validity of this CR index is encouraging, but somewhat mixed, while construct validity was evidenced through interaction between CR, brain, and word reading ability. Future research would benefit from optimization of the CR index through careful selection of brain variables for a pediatric sample.

Grey matter abnormalities in major depressive disorder patients with suicide attempts: A systematic review of age-specific differences

BACKGROUND

Previous studies have reported alterations in brain structure in major depressive disorder (MDD) patients with suicide attempts. However, age-related changes in suicidal MDD patients remain unclear.

METHODS

We performed a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Embase, PubMed, and Web of Science were searched to identify relevant studies from inception to January 2023. All voxel-based and surface-based morphometry studies comparing suicidal MDD patients to MDD or healthy controls were included. Studies were then grouped by age range (old, middle-age, adolescent) and the commonalities and age-related structural brain alterations were summarized. The included studies were evaluated using the Newcastle-Ottawa Scale (NOS).

RESULTS

A total of 17 studies met the inclusion criteria, including 3 of late-life depression (LLD) patients, 11 of middle-aged depression (MAD) patients, and 3 of adolescent depression (AOD) patients. The majority of studies had moderate to high NOS scores, indicating good quality. Patients in all three age groups exhibited extensive alterations in the lateral, medial, and orbital regions of the frontal lobes. Furthermore, suicidal MAD patients showed a specific decrease in the gray matter volume of the dorsolateral prefrontal cortex compared to suicidal LLD patients. Cortical thickness and left angular gyrus volume were decreased in suicidal MAD and suicidal LLD patients, but increased in suicidal AOD patients.

CONCLUSION

This systematic review summarizes structural brain changes in suicidal MDD patients at three age groups: elderly, middle-aged, and adolescent. These findings help elucidate the common circuitry of MDD related to suicide over the lifespan and highlight unique circuitry associated with different ages. These findings may help predict the risk of suicide in MDD patients at different ages.

A Systematic Review of MRI Studies and the "Emotional paiN and social Disconnect (END)" Brain Model of Suicidal Behavior in Youth

Introduction

Risk of suicidal ideation and suicidal behaviors greatly increases during adolescence, and rates have risen dramatically over the past two decades. However, few risk factors or biomarkers predictive of suicidal ideation or attempted suicide have been identified in adolescents. Neuroimaging correlates hold potential for early identification of adolescents at increased risk of suicidality and risk stratification for those at high risk of suicide attempt.

Methods

In this systematic review, we evaluated neural regions and networks associated with suicidal ideation and suicide attempt in adolescents derived from magnetic resonance imaging (MRI) studies. A total of 28 articles were included in this review.

Results

After descriptively synthesizing the literature, we propose the Emotional paiN and social Disconnect (END) model of adolescent suicidality and present two key neural circuits: (1) the emotional/mental pain circuit and (2) the social disconnect/distortion circuit. In the END model, the emotional pain circuit-consisting of the cerebellum, amygdala, and hippocampus-shows similar aberrations in adolescents with suicidal ideation as in those with a history of a suicide attempt (but to a smaller degree). The social disconnect circuit is unique to adolescent suicide attempters and includes the lateral orbitofrontal cortex (OFC), the temporal gyri, and the connections between them.

Conclusion

Our proposed END brain model of suicidal behavior in youth, if confirmed by future prospective studies, can have implications for clinical goals of early detection, risk stratification, and intervention development. Treatments that target emotional pain and social disconnect may be ideal interventions for reducing suicidality in adolescents.

Greater white matter hyperintensities and the association with executive function in suicide attempters with late-life depression

Late-life depression (LLD) is associated with greater risk of suicide and white matter hyperintensities (WMH), which are also found in suicide attempters regardless of age. Greater periventricular WMH are related to worse cognitive function. We investigated the spatial distribution of WMH in suicide attempters with LLD and its association with cognitive function. We recruited 114 participants with LLD (34 with history of suicide attempt and 80 without) and 47 older adult controls (individuals without LLD or history of suicide attempt). WMH were quantified by an automated segmentation algorithm and were classified into different regions. Suicide attempters with LLD had significantly higher global WMH (F3, 150 = 2.856, p = 0.039) and periventricular WMH (F3, 150 = 3.635, p = 0.014) compared to other groups. Suicide attempters with high WMH had significantly lower executive function, which could be an underlying mechanism for cognitive decline in older adults with suicidality.

Increased Amygdala-Paracentral Lobule/Precuneus Functional Connectivity Associated With Patients With Mood Disorder and Suicidal Behavior

Mood disorder patients have greater suicide risk than members of the general population, but how suicidal behavior relates to brain functions has not been fully elucidated. This study investigated how functional connectivity (FC) values between the right/left amygdala and the whole brain relate to suicidal behavior in patients with mood disorder. The participants in this study were 100 mood disorder patients with suicidal behavior (SB group), 120 mood disorder patients with non-suicidal behavior (NSB group), and 138 age- and gender-matched healthy controls (HC group). Whole-brain FC values among the three groups were compared using an analysis of covariance (ANCOVA). Compared to the NSB and HC groups, increased FC values in the right amygdala-bilateral paracentral lobule/precuneus circuit were observed in the SB group (Bonferroni-corrected, p < 0.017). The FC values in the NSB group did not differ significantly from those in the HC group (Bonferroni-corrected, p > 0.017). Moreover, there were no significant differences in FC values between mood disorder patients with suicide attempt (SA group) and mood disorder patients with suicidal ideation (SI group), while the FC values between the right amygdala and bilateral paracentral lobule/precuneus in the SA group were higher than the mean in the SI group. These findings suggest that right amygdala-paracentral lobule/precuneus dysfunction has an important role in patients with mood disorder and suicidal behavior.

Prevalence of white matter hyperintensities is not elevated in a large sample of adolescents and young adults with bipolar disorder

OBJECTIVE

The increased prevalence rate of white matter hyperintensities is one of the most consistently reported brain abnormalities in adults with bipolar disorder. However, findings in children and adolescents with bipolar disorder are less consistent. Prior studies have been constrained by small sample sizes and/or poor age- and sex-matching of healthy controls. We examined this topic in the largest sample of adolescents with bipolar disorder to date.

METHODS

T2-weighted 3-Tesla magnetic resonance imaging data were acquired for 83 adolescents with bipolar disorder diagnosed via the Kiddie Schedule for Affective Disorders and the Schizophrenia, Present and Lifetime version semi-structured interview and 64 age- and sex-matched healthy controls. All acquired scans were examined by neuroradiologists and the presence or absence of white matter hyperintensities was determined for each participant.

RESULTS

The prevalence of white matter hyperintensities did not differ between adolescents with bipolar disorder (13.3%) and controls (21.9%; χ2 = 1.90; p = 0.168).

CONCLUSION

In contrast to the study hypothesis, the prevalence of white matter hyperintensities was not higher in adolescents with bipolar disorder than controls. The large sample size and good matching for age and sex bolster the reliability of this negative finding. Future studies are warranted to evaluate the prevalence, incidence, and predictors of white matter hyperintensities in early-onset bipolar disorder prospectively.

Imaging suicidal thoughts and behaviors: a comprehensive review of 2 decades of neuroimaging studies

Identifying brain alterations that contribute to suicidal thoughts and behaviors (STBs) are important to develop more targeted and effective strategies to prevent suicide. In the last decade, and especially in the last 5 years, there has been exponential growth in the number of neuroimaging studies reporting structural and functional brain circuitry correlates of STBs. Within this narrative review, we conducted a comprehensive review of neuroimaging studies of STBs published to date and summarize the progress achieved on elucidating neurobiological substrates of STBs, with a focus on converging findings across studies. We review neuroimaging evidence across differing mental disorders for structural, functional, and molecular alterations in association with STBs, which converges particularly in regions of brain systems that subserve emotion and impulse regulation including the ventral prefrontal cortex (VPFC) and dorsal PFC (DPFC), insula and their mesial temporal, striatal and posterior connection sites, as well as in the connections between these brain areas. The reviewed literature suggests that impairments in medial and lateral VPFC regions and their connections may be important in the excessive negative and blunted positive internal states that can stimulate suicidal ideation, and that impairments in a DPFC and inferior frontal gyrus (IFG) system may be important in suicide attempt behaviors. A combination of VPFC and DPFC system disturbances may lead to very high risk circumstances in which suicidal ideation is converted to lethal actions via decreased top-down inhibition of behavior and/or maladaptive, inflexible decision-making and planning. The dorsal anterior cingulate cortex and insula may play important roles in switching between these VPFC and DPFC systems, which may contribute to the transition from suicide thoughts to behaviors. Future neuroimaging research of larger sample sizes, including global efforts, longitudinal designs, and careful consideration of developmental stages, and sex and gender, will facilitate more effectively targeted preventions and interventions to reduce loss of life to suicide.

Neuroimaging Studies of Suicidal Behavior and Non-suicidal Self-Injury in Psychiatric Patients: A Systematic Review

Background: With around 800,000 people taking their own lives every year, suicide is a growing health concern. Understanding the factors that underlie suicidality and identifying specific variables associated with increased risk is paramount for increasing our understanding of suicide etiology. Neuroimaging methods that enable the investigation of structural and functional brain markers in vivo are a promising tool in suicide research. Although a number of studies in clinical samples have been published to date, evidence about neuroimaging correlates for suicidality remains controversial. Objective: Patients with mental disorders have an increased risk for both suicidal behavior and non-suicidal self-injury. This manuscript aims to present an up-to-date overview of the literature on potential neuroimaging markers associated with SB and NSSI in clinical samples. We sought to identify consistently reported structural changes associated with suicidal symptoms within and across psychiatric disorders. Methods: A systematic literature search across four databases was performed to identify all English-language neuroimaging articles involving patients with at least one psychiatric diagnosis and at least one variable assessing SB or NSSI. We evaluated and screened evidence in these articles against a set of inclusion/exclusion criteria and categorized them by disease, adhering to the PRISMA guidelines. Results: Thirty-three original scientific articles investigating neuroimaging correlates of SB in psychiatric samples were found, but no single article focusing on NSSI alone. Associations between suicidality and regions in frontal and temporal cortex were reported by 15 and 9 studies across four disorders, respectively. Furthermore, differences in hippocampus were reported by four studies across three disorders. However, we found a significant lack of replicability (consistency in size and direction) of results across studies. Conclusions: Our systematic review revealed a lack of neuroimaging studies focusing on NSSI in clinical samples. We highlight several potential sources of bias in published studies, and conclude that future studies should implement more rigorous study designs to minimize bias risk. Despite several studies reporting associations between SB and anatomical differences in the frontal cortex, there was a lack of consistency across them. We conclude that better-powered samples, standardized neuroimaging and analytical protocols are needed to continue advancing knowledge in this field.

Biomarkers of Suicide Attempt Behavior: Towards a Biological Model of Risk

PURPOSE OF REVIEW

The rising suicide rate in the USA will not be reversed without improved risk assessment and prevention practices. To date, the best method for clinicians to assess a patient's risk for suicide is screening for past suicide attempts in the patient and their family. However, neuroimaging, genomic, and biochemical studies have generated a body of findings that allow description of an initial heuristic biological model for suicidal behavior that may have predictive value.

RECENT FINDINGS

We review studies from the past 3 years examining potential biological predictors of suicide attempt behavior. We divide findings into two major categories: (1) structural and functional brain imaging findings and (2) biochemical and genomic findings encompassing several systems, including major neurotransmitters (serotonin, catecholamines, GABA, and glutamate), the hypothalamic pituitary adrenal (HPA) axis, the inflammasome, lipids, and neuroplasticity. The biomarkers that appear promising for assessing suicide risk in clinical settings include indices of serotonergic function, inflammation, neuronal plasticity, and lipids.

Association between abnormal default mode network activity and suicidality in depressed adolescents

BACKGROUND

Suicide is the second leading cause of death among 15- to 29-year-olds in China, and 60 % of suicidal patients have a history of depression. Previous brain imaging studies have shown that depression and suicide may be associated with abnormal activity in default mode network (DMN) regions. However, no study has specifically investigated the relationship between DMN functional activity and suicidal behavior in depressed individuals. Therefore, in the present study, we directly investigated features of DMN brain activity in adolescent patients with histories of depression and attempted suicide.

METHODS

A total of 35 sex- and age-matched suicidal depressed patients were compared with 18 non-suicidal depressed patients and 47 healthy controls. We explored functional activity changes in DMN regions that could be associated with suicidal behavior by comparing resting-state functional magnetic resonance imaging (rs-fMRI) signals using independent component analysis (ICA). Scores on six clinical scales that measure depression severity (Hamilton Depression Scale (HDRS) and Beck Depression Inventory (BDI)) and suicidal traits (Barratt Impulsiveness Scale (BIS-11), Suicide Attitude Questionnaire (SAQ), Beck Hopelessness Scale (BHS), and Scale for Suicide Ideation (SSI)) were compared in the three groups.

RESULTS

Compared with the healthy controls, all of the evaluated depressed patients showed increased functional connectivity in select DMN regions. The suicidal patients showed increased connectivity in the left cerebellum and decreased connectivity in the right posterior cingulate cortex (PCC), whereas the non-suicidal depressed patients showed increased connectivity in the left superior frontal gyrus, left lingual gyrus and right precuneus and decreased connectivity in the left cerebellum. Compared to the non-suicidal patients, the suicidal patients showed increased connectivity in the left cerebellum and the left lingual gyrus and decreased connectivity in the right precuneus. No differences in the scores of any clinical scales were found between the suicidal and non-suicidal depressed patients.

CONCLUSIONS

Collectively, our results highlight the importance of the DMN in the pathophysiology of depression and suggest that suicidal behavior in depressed adolescents may be related to abnormal functional connectivity in the DMN. In particular, abnormal connectivity in the PCC/precuneus and left cerebellum might be a predictor of suicidal behavior in depressed adolescent patients.

The underlying neurobiology of key functional domains in young people with mood and anxiety disorders: a systematic review

BACKGROUND

Mood and anxiety disorders are leading causes of disability and mortality, due largely to their onset during adolescence and young adulthood and broader impact on functioning. Key factors that are associated with disability and these disorders in young people are social and economic participation (e.g. education, employment), physical health, suicide and self-harm behaviours, and alcohol and substance use. A better understanding of the objective markers (i.e. neurobiological parameters) associated with these factors is important for the development of effective early interventions that reduce the impact of disability and illness persistence.

METHODS

We systematically reviewed the literature for neurobiological parameters (i.e. neuropsychology, neuroimaging, sleep-wake and circadian biology, neurophysiology and metabolic measures) associated with functional domains in young people (12 to 30 years) with mood and/or anxiety disorders.

RESULTS

Of the one hundred and thirty-four studies selected, 7.6 % investigated social and economic participation, 2.1 % physical health, 15.3 % suicide and self-harm behaviours, 6.9 % alcohol and substance use, whereas the majority (68.1 %) focussed on clinical syndrome.

CONCLUSIONS

Despite the predominance of studies that solely examine the clinical syndrome of young people the literature also provides evidence of distinct associations among objective measures (indexing various aspects of brain circuitry) and other functional domains. We suggest that a shift in focus towards characterising the mechanisms that underlie and/or mediate multiple functional domains will optimise personalised interventions and improve illness trajectories.

The impact of periventricular white matter lesions in patients with bipolar disorder type I

INTRODUCTION

White matter hyperintensities (WMHs) are one the most common neuroimaging findings in patients with bipolar disorder (BD). It has been suggested that WMHs are associated with impaired insight in schizophrenia and schizoaffective patients; however, the relationship between insight and WMHs in BD type I has not been directly investigated.

METHODS

Patients with BD-I (148) were recruited and underwent brain magnetic resonance imaging (MRI). Affective symptoms were assessed using Young Mania Rating Scale (YMRS) and Hamilton Depression Rating Scale (HDRS17); the presence of impaired insight was based on the corresponding items of YMRS and HDRS17.

RESULTS

Multiple punctate periventricular WMHs (PWMHs) and deep WMHs (DWMHs) were observed in 49.3% and 39.9% of the cases, respectively. Subjects with lower insight for mania had significantly more PWMHs (54.6% vs 22.2%; p < 0.05) when compared to BD-I patients with higher insight for mania. The presence of PWMHs was independently associated with lower insight for mania: patients who denied illness according to the YMRS were 4 times more likely to have PWMHs (95% CI: 1.21/13.42) than other patients.

CONCLUSIONS

Impaired insight in BD-I is associated with periventricular WMHs. The early identification of BD-I subjects with PWMHs and impaired insight may be crucial for clinicians.

Magnetic resonance imaging markers of suicide attempt and suicide risk in adolescents

More than 36,000 people in the United States die from suicide annually, and suicide is the third leading cause of death in adolescence. Adolescence is a time of high risk for suicidal behavior, as well as a time that intervention and treatment may have the greatest impact because of structural brain changes and significant psychosocial development during this period. Functional and structural neuroimaging studies in adults who have attempted suicide suggest distinct gray matter volume abnormalities in cortical regions, as well as prefrontal cortical and dorsal anterior cingulate gyrus neural circuitry differences compared with affective and healthy adult controls. Recent functional neuroimaging studies in adolescents with a history of suicide attempt suggest differences in the attention and salience networks compared with adolescents with depression and no history of suicide attempt and healthy controls when viewing angry faces. In contrast, no abnormalities are seen in these areas in the absence of emotional stimuli. These networks may represent promising targets for future neuroimaging studies to identify markers of risk for future suicide attempt in adolescents.

Is there a neuroanatomical basis of the vulnerability to suicidal behavior? A coordinate-based meta-analysis of structural and functional MRI studies

Objective: We conducted meta-analyses of functional and structural neuroimaging studies comparing adolescent and adult individuals with a history of suicidal behavior and a psychiatric disorder to psychiatric controls in order to objectify changes in brain structure and function in association with a vulnerability to suicidal behavior.

Methods: Magnetic resonance imaging studies published up to July 2013 investigating structural or functional brain correlates of suicidal behavior were identified through computerized and manual literature searches. Activation foci from 12 studies encompassing 475 individuals, i.e., 213 suicide attempters and 262 psychiatric controls were subjected to meta-analytical study using anatomic or activation likelihood estimation (ALE).

Result: Activation likelihood estimation revealed structural deficits and functional changes in association with a history of suicidal behavior. Structural findings included reduced volumes of the rectal gyrus, superior temporal gyrus and caudate nucleus. Functional differences between study groups included an increased reactivity of the anterior and posterior cingulate cortices.

Discussion: A history of suicidal behavior appears to be associated with (probably interrelated) structural deficits and functional overactivation in brain areas, which contribute to a decision-making network. The findings suggest that a vulnerability to suicidal behavior can be defined in terms of a reduced motivational control over the intentional behavioral reaction to salient negative stimuli.

Neurobiological risk factors for suicide: insights from brain imaging

CONTEXT

This article reviews neuroimaging studies on neural circuitry associated with suicide-related thoughts and behaviors to identify areas of convergence in findings. Gaps in the literature for which additional research is needed are identified.

EVIDENCE ACQUISITION

A PubMed search was conducted and articles published before March 2014 were reviewed that compared individuals who made suicide attempts to those with similar diagnoses who had not made attempts or to healthy comparison subjects. Articles on adults with suicidal ideation and adolescents who had made attempts, or with suicidal ideation, were also included. Reviewed imaging modalities included structural magnetic resonance imaging, diffusion tensor imaging, single photon emission computed tomography, positron emission tomography, and functional magnetic resonance imaging.

EVIDENCE SYNTHESIS

Although many studies include small samples, and subject characteristics and imaging methods vary across studies, there were convergent findings involving the structure and function of frontal neural systems and the serotonergic system.

CONCLUSIONS

These initial neuroimaging studies of suicide behavior have provided promising results. Future neuroimaging efforts could be strengthened by more strategic use of common data elements and a focus on suicide risk trajectories. At-risk subgroups defined by biopsychosocial risk factors and multidimensional assessment of suicidal thoughts and behaviors may provide a clearer picture of the neural circuitry associated with risk status-both current and lifetime. Also needed are studies investigating neural changes associated with interventions that are effective in risk reduction.

The neurobiology of suicide

The stress-diathesis model posits that suicide is the result of an interaction between state-dependent (environmental) stressors and a trait-like diathesis or susceptibility to suicidal behaviour, independent of psychiatric disorders. Findings from post-mortem studies of the brain and from genomic and in-vivo neuroimaging studies indicate a biological basis for this diathesis, indicating the importance of neurobiological screening and interventions, in addition to cognitive and mood interventions, in the prevention of suicide. Early-life adversity and epigenetic mechanisms might explain some of the link between suicide risk and brain circuitry and neurochemistry abnormalities. Results from a range of studies using diverse designs and post-mortem and in-vivo techniques show impairments of the serotonin neurotransmitter system and the hypothalamic-pituitary-adrenal axis stress-response system in the diathesis for suicidal behaviour. These impairments manifest as impaired cognitive control of mood, pessimism, reactive aggressive traits, impaired problem solving, over-reactivity to negative social signs, excessive emotional pain, and suicidal ideation, leading to suicidal behaviour. Biomarkers related to the diathesis might help to inform risk-assessment procedures and treatment choice in the prevention of suicide.

A diffusion tensor imaging study of suicide attempters

BACKGROUND

Few studies have examined white matter abnormalities in suicide attempters using diffusion tensor imaging (DTI). This study sought to identify white matter regions altered in individuals with a prior suicide attempt.

METHODS

DTI scans were acquired in 13 suicide attempters with major depressive disorder (MDD), 39 non-attempters with MDD, and 46 healthy participants (HP). Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were determined in the brain using two methods: region of interest (ROI) and tract-based spatial statistics (TBSS). ROIs were limited a priori to white matter adjacent to the caudal anterior cingulate cortex, rostral anterior cingulate cortex, dorsomedial prefrontal cortex, and medial orbitofrontal cortex.

RESULTS

Using the ROI approach, suicide attempters had lower FA than MDD non-attempters and HP in the dorsomedial prefrontal cortex. Uncorrected TBSS results confirmed a significant cluster within the right dorsomedial prefrontal cortex indicating lower FA in suicide attempters compared to non-attempters. There were no differences in ADC when comparing suicide attempters, non-attempters and HP groups using ROI or TBSS methods.

CONCLUSIONS

Low FA in the dorsomedial prefrontal cortex was associated with a suicide attempt history. Converging findings from other imaging modalities support this finding, making this region of potential interest in determining the diathesis for suicidal behavior.

Differences between suicide attempters and nonattempters in depressed older patients: depression severity, white-matter lesions, and cognitive functioning

OBJECTIVES

The population of older adults with major depressive disorder (MDD) has the highest rate of suicide. White-matter brain lesions (WML) are a potential biologic marker for suicidality in young and middle-aged adults and are correlated with cognitive impairment in older adults. In this study of older patients with MDD, we examined 1) if a history of suicide attempts was associated with a more severe course of MDD; 2) if WML are a biologic marker for suicide; and 3) if suicide attempt history is associated with cognitive impairment mediated by WML.

SETTING

Data from the Neurocognitive Outcomes of Depression in the Elderly study.

PARTICIPANTS

Depressed patients (60+) who had ever attempted suicide (n = 23) were compared with depressed patients (60+) who had not attempted suicide (n = 223).

MEASUREMENTS

Baseline and follow-up assessments were obtained for depressive symptoms (every 3 months) and cognitive functioning (every 6 months) over 2 years. Three magnetic resonance imaging scans were conducted.

RESULTS

At baseline, suicide attempters reported more severe past and present symptoms (e.g., depressive symptoms, current suicidal thoughts, psychotic symptoms, earlier age of onset, and more lifetime episodes) than nonattempters. Suicide attempters had more left WML at baseline, and suicide attempt history predicted a greater growth in both left and right WML. WML predicted cognitive decline; nonetheless, a history of suicide attempt was unrelated to cognitive functioning.

CONCLUSIONS

Severity of depressive symptoms and WML are associated with suicide attempts in geriatric depressed patients. Suicide attempts predicted neurologic changes, which may contribute to poorer long-term outcomes in elder attempters.

Enlarged thalamic volumes and increased fractional anisotropy in the thalamic radiations in veterans with suicide behaviors

Post-mortem studies have suggested a link between the thalamus, psychiatric disorders, and suicide. We evaluated the thalamus and anterior thalamic radiations (ATR) in a group of Veterans with and without a history of suicidal behavior (SB) to determine if thalamic abnormalities were associated with an increased risk of SB. Forty Veterans with mild traumatic brain injury (TBI) and no SB (TBI-SB), 19 Veterans with mild TBI and a history of SB (TB + SB), and 15 healthy controls (HC) underwent magnetic resonance imaging scanning including a structural and diffusion tensor imaging scan. SBs were evaluated utilizing the Columbia Suicide Rating Scale and impulsivity was measured using the Barratt Impulsiveness Scale (BIS). Differences in thalamic volumes and ATR fractional anisotropy (FA) were examined between (1) TBI + SB versus HC and (2) TBI + SB versus combined HC and TBI-SB and (3) between TBI + SB and TBI-SB. Left and right thalamic volumes were significantly increased in those with TBI + SB compared to the HC, TBI-SB, and the combined group. Veterans with TBI + SB had increased FA bilaterally compared to the HC, HC and TBI-SB group, and the TBI-SB only group. Significant positive associations were found for bilateral ATR and BIS in the TBI + SB group. Our findings of thalamic enlargement and increased FA in individuals with TBI + SB suggest that this region may be a biomarker for suicide risk. Our findings are consistent with previous evidence indicating that suicide may be associated with behavioral disinhibition and frontal-thalamic-limbic dysfunction and suggest a neurobiologic mechanism that may increase vulnerability to suicide.

Biological indicators of suicide risk in youth with mood disorders: what do we know so far?

Suicidal behaviour in youth is a major public health concern worldwide, and youth in the early stages of a primary mood disorder are an identifiable high-risk population. Neurobiological research in youth at risk for suicidality has sought to investigate the most promising parameters from research in adults. The present paper provides an overview of the current findings of neurobiological research in children and adolescents with mood disorders and suicidality including genetic/epigenetic findings, neuro-hormonal and immunological investigations. Longitudinal research in high-risk youth is a powerful way to investigate the influences and their pathways in determining suicidal risk in the context of a developing mood disorder. In the meantime, there are clear clinical indicators of risk to help identify youth who would benefit from close surveillance and early intervention.

White matter hyperintensities and self-reported depression in a sample of patients with chronic headache

White matter hyperintensities (WMH) have been associated with mood disorders in psychiatric patients. In the present study, we aimed to assess whether WMHs are associated with depressive symptoms and different sensitivity of the behavioral inhibition (BIS), and activation (BAS) systems in patients with chronic headache. Participants were 85 adult outpatients (16 men and 69 women) with a diagnosis of chronic headache. All of the patients underwent brain magnetic resonance imaging (MRI) and were administered the BIS/BAS scales and the Center for Epidemiologic Studies Depression Scale. Above 40 % of patients had periventricular WMHs (PWMHs) and almost 98 % had deep WMHs (DWMHs). Patients with PWMHs reported fewer depressive symptoms than patients without PWMHs. Patients with more severe DWMHs (compared with patients with mild or without DWMH lesions) were older and reported lower scores on the drive dimension of the BIS/BAS scales. In multivariate analyses, patients with PWMHs were 1.06 times more likely to report fewer depressive symptoms than patients without PWMHs. WMH lesions in patients with chronic headache were associated with less depression severity.

Relationship between suicidality and impulsivity in bipolar I disorder: a diffusion tensor imaging study

BACKGROUND

Impulsivity is characteristic of individuals with bipolar disorder and may be a contributing factor to the high rate of suicide in patients with this disorder. Although white matter abnormalities have been implicated in the pathophysiology of bipolar disorder, their relationship to impulsivity and suicidality in this disorder has not been well-investigated.

METHODS

Diffusion tensor imaging scans were acquired in 14 bipolar disorder patients with a prior suicide attempt, 15 bipolar disorder patients with no prior suicide attempt, and 15 healthy volunteers. Bipolar disorder patients received clinical assessments including measures of impulsivity, depression, mania, and anxiety. Images were processed using the Tract-Based Spatial Statistics method in the FSL software package.

RESULTS

Bipolar disorder patients with a prior suicide attempt had lower fractional anisotropy (FA) within the left orbital frontal white matter (p < 0.05, corrected) and higher overall impulsivity compared to patients without a previous suicide attempt. Among patients with a prior suicide attempt, FA in the orbital frontal white matter region correlated inversely with motor impulsivity.

CONCLUSIONS

Abnormal orbital frontal white matter may play a role in impulsive and suicidal behavior among patients with bipolar disorder.

The suicidal mind and brain: a review of neuropsychological and neuroimaging studies

OBJECTIVES. We aimed at reviewing studies exploring dysfunctional cognitive processes, and their neuroanatomical basis, in suicidal behaviour, and to develop a neurocognitive working model. Methods. A literature search was conducted. RESULTS. Several limitations were found. The main reported neuropsychological findings are a higher attention to specific negative emotional stimuli, impaired decision-making, lower problem-solving abilities, reduced verbal fluency, and possible reduced non-specific attention and reversal learning in suicide attempters. Neuroimaging studies mainly showed the involvement of ventrolateral orbital, dorsomedial and dorsolateral prefrontal cortices, the anterior cingulate gyrus, and, to a lesser extent, the amygdala. In addition, alterations in white matter connections are suggested. CONCLUSIONS. These studies support the concept of alterations in suicidal behaviour distinct from those of comorbid disorders. We propose that a series of neurocognitive dysfunctions, some with trait-like characteristics, may facilitate the development of a suicidal crisis during stressful circumstances: (1) an altered modulation of value attribution, (2) an inadequate regulation of emotional and cognitive responses, and (3) a facilitation of acts in an emotional context. This preliminary model may represent a framework for the design of future studies on the pathophysiology, prediction and prevention of these complex human behaviours.

Affective temperamental profiles are associated with white matter hyperintensity and suicidal risk in patients with mood disorders

BACKGROUND

Patients with white matter hyperintensities (WMH) may be at higher risk for affective disorders and suicide. Affective temperaments may play a significant role in mood disorders. This study aimed to evaluate the eventual association between WMH, affective temperaments and suicidal behaviour in major affective disorder.

METHODS

A total of 318 patients with major affective disorders were consecutively admitted as psychiatric inpatient. A total of 247 were included and given, brain magnetic resonance imaging (MRI) and assessed with the Mini International Neuropsychiatric Interview (MINI), the Beck Hopelessness Scale (BHS), the Hamilton Depression Rating Scale (HDRS(17)), the Young Mania Rating Scale (YMRS) and the Temperament Evaluation of Memphis, Pisa, Paris and San Diego (TEMPS-A).

RESULTS

A total of 48% of patients had periventricular WMH (PWMH) and 39% of them had deep WMH (DWMH). Patients with higher dysthymia and lower hyperthymia (H-DCIA group) were more likely to have higher BHS scores (BHS≥9=77% vs. 52%; p>0.001), more WMH (46% vs. 29%; χ(2)(n=3)=9.90; p<0.05), higher MINI suicidal risk (54% vs. 42%; p<0.05), and more recent suicide attempts (24% vs. 14%; p<0.05), than patients with higher hyperthymia and lower dysthymia (H-H group).

LIMITATIONS

The small sample size did not allow the generalization of the present findings.

CONCLUSIONS

Differences among temperament groups measured by the TEMPS-A are associated with differences in their MRIs, indicating that different temperament profiles are associated with differences in the subcortical structures of the brain. The implications of the results were discussed.

Suicidal brains: a review of functional and structural brain studies in association with suicidal behaviour

Evidence of an association between a vulnerability to suicidal behaviour and neurobiological abnormalities is accumulating. Post-mortem studies have demonstrated structural and biochemical changes in the brains of suicide victims. More recently, imaging techniques have become available to study changes in the brain in vivo. This systematic review of comparative imaging studies of suicidal brains shows that changes in the structure and functions of the brain in association with suicidal behaviour are mainly found in the orbitofrontal and dorsolateral parts of the prefrontal cortex. Correlational studies suggest that these changes relate to neuropsychological disturbances in decision-making, problem solving and fluency, respectively. As a consequence, the findings from these studies suggest that suicidal behaviour is associated with (1) a particular sensitivity to social disapproval (2) choosing options with high immediate reward and (3) a reduced ability to generate positive future events. Further study is needed to elaborate these findings and to investigate to what extent changes in the structure and function of suicidal brains are amenable to psychological and/or biological interventions.

White matter hyperintensities and their association with suicidality in major affective disorders: a meta-analysis of magnetic resonance imaging studies

INTRODUCTION

Individuals who have deep and periventricular white matter hyperintensities may have a higher risk for suicidal behavior. There are mixed results in the literature regarding whether unipolar or bipolar patients who have attempted suicide have more deep white matter hyperintensities (DWMH) or periventricular hyperintensities (PVH) relative to those who have no history of suicide attempts.

METHODS

A meta-analysis of studies examining white matter hyperintensities (WMH) in mood disorder patients with and without a history of suicide attempts was performed.

RESULTS

Four studies, including a total of 173 patients who attempted suicide and 183 who did not attempt suicide, were included. A significantly higher number of attempters were found to have WMH than non-attempters. Unipolar depressed patients who had attempted suicide had 1.9 times more DWMH and 2.1 times more PVH than those who did not. Bipolar patients who had attempted suicide had 5.4 times more PVH than those who had not. Taken together, unipolar and bipolar patients who had attempted suicide had 2.8 times more DWMH and 4.5 times more PVH than those who had never attempted suicide.

CONCLUSION

These findings raise the possibility that WMH are biological substrates of symptoms that lead to suicidal behavior.

Altered white matter microstructure in adolescents with major depression: a preliminary study

OBJECTIVE

Major depressive disorder (MDD) occurs frequently in adolescents, but the neurobiology of depression in youth is poorly understood. Structural neuroimaging studies in both adult and pediatric populations have implicated frontolimbic neural networks in the pathophysiology of MDD. Diffusion tensor imaging (DTI), which measures white matter (WM) microstructure, is a promising tool for examining neural connections and how they may be abnormal in MDD.

METHOD

We used two separate approaches to analyze DTI data in adolescents with MDD (n = 14) compared with healthy volunteers (n = 14).

RESULTS

The first, hypothesis-driven approach was to use probabilistic tractography to delineate tracts arising from the subgenual anterior cingulate cortex (ACC). Adolescents with MDD demonstrated lower fractional anisotropy (FA) in the WM tract connecting subgenual ACC to amygdala in the right hemisphere. The second, exploratory approach was to conduct a voxelwise comparison of FA. This analysis revealed 10 clusters where adolescents with MDD had significantly lower (uncorrected) FA than the healthy group within WM tracts including right and left uncinate and supragenual cingulum.

CONCLUSIONS

These preliminary data support the hypothesis that altered WM microstructure in frontolimbic neural pathways may contribute to the pathophysiology of MDD in adolescents.

Assessment and treatment of suicide risk in bipolar disorders

Completed suicide and suicide attempts are major issues in the management of bipolar disorders. There is evidence that suicide rates among these patients are more than 20-fold higher than the general population and, furthermore, suicidal behavior is much more lethal in bipolar disorder than in the general population. Patients with mood disorders may sometimes exhibit highly perturbed mixed states, which usually increase the risk of suicide. Such states are particularly frequent in bipolar II patients, especially if patients are treated with antidepressant monotherapy (unprotected by mood stabilizers), when depression switches into mania (or vice versa), or when depression lifts and functioning approaches normality. Researchers worldwide agree that treatment involving lithium is the best way to protect patients from suicide risk. Psychosocial activities, including psychoeducation, can protect bipolar patients either directly or, more probably, indirectly by increasing adherence to treatment and helping in daily difficulties that otherwise may lead to demoralization or hopelessness. An extensive understanding of the psychosocial circumstances and the psychopathology of bipolar patients (including temperament) may help clinicians describe the clinical picture accurately and prevent suicidal behavior in these patients.

Left orbitofrontal and superior temporal gyrus structural changes associated to suicidal behavior in patients with schizophrenia

Suicidal attempts are relatively frequent and clinically relevant in patients with schizophrenia. Recent studies have found gray matter differences in suicidal and non-suicidal depressive patients. However, no previous neuroimaging study has investigated possible structural abnormalities associated to suicidal behaviors in patients with schizophrenia. A whole-brain magnetic resonance voxel-based morphometric examination was performed on 37 male patients meeting the DSM-IV criteria for schizophrenia. Thirteen (35.14%) patients had attempted suicide. A non-parametric permutation test was computed to perform the comparability between groups. An analysis of covariance (AnCova) model was constructed with a statistical threshold of p<0.05 corrected for multiple comparisons. After controlling for age and severity of illness, results showed significant gray matter density reduction in left superior temporal lobe (p=0.03) and left orbitofrontal cortex (p=0.04) in patients who had attempted suicide when comparing with non-suicidal patients. Although sample size limitations and potential clinical heterogeneity preclude definitive conclusions, these data point to structural differences in key cerebral areas. Neuroimaging studies are necessary to expand our knowledge of biological mechanisms underlying suicide in schizophrenia.

Periventricular white matter hyperintensities as predictors of suicide attempts in bipolar disorders and unipolar depression

The aim of this study was to evaluate whether deep white matter hyperintensities (DWMH) and periventricular white matter hyperintensities (PVH) are associated with suicidal behavior in patients with major affective disorders. Subjects were 99 consecutively admitted inpatients (42 men; 57 women; mean age: 46.5 years [SD=15.2; Min./Max.=19/79]) with a diagnosis of major affective disorder (bipolar disorder type I, bipolar disorder type-II and unipolar major depressive disorder). 44.4% of the participants had made at least one previous suicide attempt. T2-weighted brain magnetic resonance images were rated for the presence and extension of WMH using the modified Fazekas scale. Patients were interviewed for clinical data on average 5 days after admission. Bivariate analyses, corrected for multiple-testing, and logistic regression analysis were used to test the association between suicide attempts and clinical variables. Attempters and nonattempters differed only in the presence of PVH--the former were more likely to have PVH. The logistic regression indicated that the presence of PVH was robustly associated with suicidal behaviors after controlling for age (OR: 8.08). In conclusion, neuroimaging measures may be markers of risk for suicidal attempts in patients with major affective disorders.

White matter hyperintensities and their associations with suicidality in patients with major affective disorders

INTRODUCTION

A large body of evidence suggests that predisposition to suicide, an important public health problem, is mediated to a certain extent by neurobiological factors. The objective of this cross-sectional study was to compare the prevalence of white matter hyperintensities (WMH) in patients with major affective disorders with and without histories of suicide attempts.

METHODS

T2-weighted magnetic resonance images (MRI) of 65 psychiatric inpatients with major depressive disorder or bipolar disorder were rated for the presence of WMH. Diagnoses, presence or absence of suicide risk and substance abuse were determined by the Mini International Neuropsychiatric Interview (MINI). Medical charts were reviewed to ascertain history of suicide attempt and basic clinical variables. Fisher's Exact Tests and logistic regression modeling were used to test the association between WMH and suicidality. Suicidal patients and controls were not matched for demographic variables and exposure to some risk factors.

RESULTS

Bivariate analysis showed that the prevalence of WMH was significantly higher in subjects with past suicide attempts (Fisher's Exact Test, p = 0.01) and other clinical indicators of elevated suicide risk. Logistic regression analyses controlling for age, sex, and several clinical risk factors supported this finding (odds ratio = 4.7; 95% confidence interval: 1.4, 16.1).

CONCLUSIONS

The increased prevalence of WMH in adults with major affective disorders and a history of suicide attempt, compared to similar patients without such a history, is consistent with previous findings in depressed children, youth and young adults. However, the association between WMH and suicidality holds true for both, depressed and bipolar patients. Our results suggest that WMH in patients with major affective disorders might be useful biological markers of suicidality.

Fronto-limbic brain structures in suicidal and non-suicidal female patients with major depressive disorder

Our knowledge about the neurobiology of suicide is limited. It has been proposed that suicidal behavior generally requires biological abnormalities concomitant with the personality trait of impulsivity/aggression, besides an acute psychiatric illness or psychosocial stressor. We investigated fronto-limbic anatomical brain abnormalities in suicidal and non-suicidal adult female patients with unipolar depression. Our sample consisted of seven suicidal unipolar patients, 10 non-suicidal unipolar patients and 17 healthy female comparison subjects. The criterion for suicidality was one or more documented lifetime suicide attempts. A 1.5T GE Signa Imaging System running version Signa 5.4.3 software was used to acquire the magnetic resonance imaging images. All anatomical structures were measured blindly, with the subjects' identities and group assignments masked. We used analysis of covariance with age and intracranial volume as covariates and the Tukey-Kramer procedure to compare suicidal patients, non-suicidal patients and healthy comparison subjects. Suicidal patients had smaller right and left orbitofrontal cortex gray matter volumes compared with healthy comparison subjects. Suicidal patients had larger right amygdala volumes than non-suicidal patients. Abnormalities in the orbitofrontal cortex and amygdala in suicidal patients may impair decision-making and predispose these patients to act more impulsively and to attempt suicide.

Neuroimaging studies of children with serious emotional disturbances: a selective review

OBJECTIVES

To critically review and integrate, from a developmental perspective, recent magnetic resonance imaging (MRI) studies of 4 childhood psychiatric disorders: schizophrenia, bipolar disorder (BD), attention-deficit hyperactivity disorder (ADHD), and major depressive disorder (MDD).

METHOD

We reviewed published reports in refereed journals. We briefly describe the major findings with respect to the brain morphometry, chemistry, and function of children with psychiatric disorders and synthesize the reports in a summary to update clinicians.

RESULTS

Some cortical grey matter abnormalities associated with schizophrenia appear to predate the onset of frank psychosis and continue to advance after the onset of psychosis, at least in more severe cases. Pediatric BD is associated with abnormalities in a circuit, thought to be involved in mood regulation, that encompasses the amygdala, striatum, and ventral PFC. Frontostriatal abnormalities are reported consistently in ADHD, potentially reflecting abnormalities in the development of cognitive control. Children with MDD show prefrontal cortical alterations that may differ in familial and nonfamilial subtypes of MDD.

CONCLUSIONS

Results from neuroimaging studies of childhood psychopathology reveal abnormalities in the developmental trajectories observed in healthy children. Although MRI has increased our understanding of the pathophysiology of these disorders, routine neuroimaging for children with severe emotional disturbances is not indicated for diagnostic purposes.

Major depressive disorder with anger attacks and subcortical MRI white matter hyperintensities

Previous reports of increased rates of cardiovascular risk factors in major depressive disorder (MDD) with anger attacks led the authors to hypothesize that MDD with anger attacks may be associated with brain vascular changes (magnetic resonance imaging white matter hyperintensities [WMHs]). Sixty-five subjects meeting DSM-III-R criteria for major depressive disorder were administered brain magnetic resonance imaging scans at 1.5T to detect T2 WMH. The severity of brain WMH was classified with the Fazekas scale. We used standardized scales to assess melancholic MDD, atypical MDD, and MDD with anger attacks. In logistic regression analyses, MDD with anger attacks was associated with higher severity of subcortical WMH and of total WMH, but not with periventricular WMH. Atypical and melancholic MDD subtypes were not significantly associated with brain WMH. In conclusion, subcortical brain vascular lesions may be more prevalent or severe in MDD with anger attacks.

Rational approaches to the neurobiologic study of youth at risk for bipolar disorder and suicide

OBJECTIVES

The aims of this paper are to provide an overview of neuroimaging findings specific to bipolar disorder and suicide, and to consider rational approaches to the design of future in vivo studies in youth at risk.

METHODS

Neuroimaging and related neurobiological literature pertaining to bipolar disorder and suicide in adult and pediatric samples was reviewed in a non-quantitative manner.

RESULTS

Specific structural and functional brain findings in bipolar disorder are described, where possible in the context of relevant current neurobiological theories of etiology. Diagnostic and prognostic implications are discussed.

CONCLUSIONS

The simultaneous use of complementary neurobiological approaches may be a powerful way of identifying and validating factors reliably associated with bipolar disorder and suicide. A profile of neurobiological markers with which to screen for bipolar disorder and suicide risk may provide for earlier and more accurate diagnosis, perhaps even in the pre- or subsyndromal stages in high-risk youth.

White matter hyperintensities and their association with suicidality in depressed young adults

INTRODUCTION

Researchers and clinicians have increasingly recognized that biological markers may help identify patients who are at risk for suicide. The objective of this retrospective, cross-sectional study was to compare the prevalence and location of white matter hyperintensities (WMH) in young inpatients with major depressive disorder (MDD) with and without histories of suicide attempts.

METHODS

T2-weighted magnetic resonance images (MRI) of 102 young psychiatric inpatients with MDD were rated for the presence of WMH. Medical charts were reviewed to ascertain history of suicide attempt, demographic and clinical variables. Fisher's Exact Tests and logistic regression modeling were used to test the association between WMH and suicidality.

RESULTS

Bivariate analysis showed that the prevalence of periventricular WMH was significantly higher in subjects with past suicide attempts (Fisher's Exact Test, p=0.02). Logistic regression analyses controlling for age, sex, and several clinical risk factors supported this finding (odds ratio=5.7; 95% confidence interval: 1.6, 21.2).

LIMITATIONS

Due to the retrospective, cross-sectional design of our study, we are unable to determine if the WMH preceded or followed past suicide attempts. The generalizability of our findings is limited since this group of inpatients is more severely ill than the general psychiatric population.

CONCLUSIONS

The increased prevalence of periventricular WMH in young adults with MDD and a history of suicide attempt, compared to similarly depressed adults without such a history, is consistent with our findings in children and youth, and suggests there might be neurobiological in addition to psychosocial risk factors for suicide.