Proceedings of the 2013 CINP summit: innovative partnerships to accelerate CNS drug discovery for improved patient care.

Central nervous system (CNS) diseases and, in particular, mental health disorders, are becoming recognized as the health challenge of the 21(st) century. Currently, at least 10% of the global population is affected by a mental health disorder, a figure that is set to increase year on year. Meanwhile, the rate of development of new CNS drugs has not increased for many years, despite unprecedented levels of investment. In response to this state of affairs, the Collegium Internationale Neuro-Psychopharmacologicum (CINP) convened a summit to discuss ways to reverse this disturbing trend through new partnerships to accelerate CNS drug discovery. The objectives of the Summit were to explore the issues affecting the value chain (i.e. the chain of activities or stakeholders that a company engages in/with to deliver a product to market) in brain research, thereby gaining insights from key stakeholders and developing actions to address unmet needs; to identify achievable objectives to address the issues; to develop action plans to bring about measurable improvements across the value chain and accelerate CNS drug discovery; and finally, to communicate recommendations to governments, the research and development community, and other relevant stakeholders. Summit outputs include the following action plans, aligned to the pressure points within the brain research-drug development value chain: Code of conduct dealing with conflict of interest issues, Prevention, early diagnosis, and treatment, Linking science and regulation, Patient involvement in trial design, definition of endpoints, etc., Novel trial design, Reproduction and confirmation of data, Update of intellectual property (IP) laws to facilitate repurposing and combination therapy (low priority), Large-scale, global patient registries, Editorials on nomenclature, biomarkers, and diagnostic tools, and Public awareness, with brain disease advocates to attend G8 meetings and World Economic Forum (WEF) Annual meetings in Davos, Switzerland. In this context Professor Barbara Sahakian recently made a formal presentation at the World Economic Forum (see Barbara Sahakian Blog from April 11, 2014, at https://forumblog.org/people/barbara-sahakian/) Full details of the discussions that formed the bases for these actions are presented in the main body of this document.

How Academic Health Systems Can Be Ready for the Next Pandemic.

The COVID-19 pandemic created significant challenges for academic health systems (AHSs) across their tripartite mission of providing clinical care, conducting research, and educating learners. Despite these challenges, AHSs played an invaluable role in responding to the pandemic. Clinicians worked tirelessly to care for patients, and institutions quickly reoriented their care delivery systems. Furthermore, AHSs played an important role in advancing science, launching studies and clinical trials to examine new vaccines and treatments for COVID-19. However, there is room for improvement; AHSs can use lessons learned from the COVID-19 pandemic to reshape their operations for the future. To prepare for the next pandemic, AHSs must modernize, adapt, and transform their clinical operations, research infrastructure, and educational programs to include public health and to build surveillance capacity for detecting, monitoring, and managing emerging outbreaks. In this Invited Commentary, the authors describe the opportunities AHSs have to build on their experiences during the COVID-19 pandemic and the ways they can take advantage of their unique strengths in each of their 3 mission areas. Within clinical care, AHSs can reach patients outside traditional clinical settings, build national and regional networks, advance data-driven insights, engage with the community, and support and protect the workforce. Within research, they can leverage data science and artificial intelligence, perform pandemic forecasting, leverage the social and behavioral sciences, conduct clinical trials, and build a research and development preparedness and operational plan. Within education, AHSs can promote remote learning, make interprofessional learning the norm, and build a system of continuing education.

Towards a scientific taxonomy of depression.

Many concepts have been introduced into the classification of depression, including manic-depressive/bipolar disorder depression, etc. Kraepelin's original concept of manic-depressive disorder has evolved into the concept of polarity, and bipolar and unipolar disorders. Psychiatric classification is characterized by an inflation of the diagnostic categories, including subtypes of depression. This rapid multiplier effect is primarily descriptive, and there is a need to rethink, in a pragmatic fashion, the classification system, in order to develop one that is likely to be of utility and which has a scientific basis. Is the time now right to ask whether there are essential conditions relevant to depression? I think that it is, and here I will introduce the notion with two such conditions. The first is early life stress disorder, and the second vascular depression. These conditions have reached a point where the data supports them as distinct entities. In this paper, the rationale for this is discussed.

Lobar distribution of lesion volumes in late-life depression: the Biomedical Informatics Research Network (BIRN).

White matter hyperintense lesions on T2-weighted images are associated with late-life depression. Little work has been carried out examining differences in lesion location between elderly individuals with and without depression. In contrast to previous studies examining total brain white matter lesion volume, this study examined lobar differences in white matter lesion volumes derived from brain magnetic resonance imaging. This study examined 49 subjects with a DSM-IV diagnosis of major depression and 50 comparison subjects without depression. All participants were age 60 years or older. White matter lesion volumes were measured in each hemisphere using a semiautomated segmentation process and localized to lobar regions using a lobar atlas created for this sample using the imaging tools provided by the Biomedical Informatics Research Network (BIRN). The lobar lesion volumes were compared against depression status. After controlling for age and hypertension, subjects with depression exhibited significantly greater total white matter lesion volume in both hemispheres and in both frontal lobes than did control subjects. Although a similar trend was observed in the parietal lobes, the difference did not reach a level of statistical significance. Models of the temporal and occipital lobes were not statistically significant. Older individuals with depression have greater white matter disease than healthy controls, predominantly in the frontal lobes. These changes are thought to disrupt neural circuits involved in mood regulation, thus increasing the risk of developing depression.

Prominent reduction in pyramidal neurons density in the orbitofrontal cortex of elderly depressed patients.

BACKGROUND: Elderly depressed patients have more vascular hyperintensities in frontal white matter and basal ganglia than elderly control subjects. Cell pathology that might be related to increased vascular hyperintensities has not been examined. METHODS: Postmortem samples from the orbitofrontal cortex (ORB) were collected in 15 elderly subjects with major depressive disorder (MDD) and 11 age-matched control subjects. Cell packing density of neurons and glia, density of pyramidal and nonpyramidal neurons, and cortical and laminar width were measured. RESULTS: The overall (layers I-VI) packing density of ORB neurons with pyramidal morphology was markedly decreased in MDD (by 30%) as compared with control subjects. Further laminar analysis of pyramidal neurons density revealed significant reductions in layers IIIc and V in MDD. In contrast, in MDD the density of nonpyramidal neurons and glia and cortical and laminar width were comparable to control values. CONCLUSIONS: In elderly subjects with depression, the density of pyramidal neurons in the ORB was particularly low in cortical layers V and III, the origin of prefronto-striatal and prefronto-cortical and prefronto-amygdalar projections. Degeneration of neurons furnishing these projections might be related to the white matter hyperintensities previously observed. Neuronal pathology seems to be more severe in elderly than in younger subjects with MDD.

Mood disorders in the medically ill: scientific review and recommendations.

OBJECTIVE: The purpose of this review is to assess the relationship between mood disorders and development, course, and associated morbidity and mortality of selected medical illnesses, review evidence for treatment, and determine needs in clinical practice and research. DATA SOURCES: Data were culled from the 2002 Depression and Bipolar Support Alliance Conference proceedings and a literature review addressing prevalence, risk factors, diagnosis, and treatment. This review also considered the experience of primary and specialty care providers, policy analysts, and patient advocates. The review and recommendations reflect the expert opinion of the authors. STUDY SELECTION/DATA EXTRACTION: Reviews of epidemiology and mechanistic studies were included, as were open-label and randomized, controlled trials on treatment of depression in patients with medical comorbidities. Data on study design, population, and results were extracted for review of evidence that includes tables of prevalence and pharmacological treatment. The effect of depression and bipolar disorder on selected medical comorbidities was assessed, and recommendations for practice, research, and policy were developed. CONCLUSIONS: A growing body of evidence suggests that biological mechanisms underlie a bidirectional link between mood disorders and many medical illnesses. In addition, there is evidence to suggest that mood disorders affect the course of medical illnesses. Further prospective studies are warranted.

Psychiatric and medical comorbidities of bipolar disorder.

OBJECTIVES: This review summarizes the literature on psychiatric and medical comorbidities in bipolar disorder. The coexistence of other Axis I disorders with bipolar disorder complicates psychiatric diagnosis and treatment. Conversely, symptom overlap in DSM-IV diagnoses hinders definition and recognition of true comorbidity. Psychiatric comorbidity is often associated with earlier onset of bipolar symptoms, more severe course, poorer treatment compliance, and worse outcomes related to suicide and other complications. Medical comorbidity may be exacerbated or caused by pharmacotherapy of bipolar symptoms. METHODS: Articles were obtained by searching MEDLINE from 1970 to present with the following search words: bipolar disorder AND, comorbidity, anxiety disorders, eating disorder, alcohol abuse, substance abuse, ADHD, personality disorders, borderline personality disorder, medical disorders, hypothyroidism, obesity, diabetes mellitus, multiple sclerosis, lithium, valproate, lamotrigine, carbamazepine, atypical antipsychotics. Articles were prioritized for inclusion based on the following considerations: sample size, use of standardized diagnostic criteria and validated methods of assessment, sequencing of disorders, quality of presentation. RESULTS: Although the literature establishes a strong association between bipolar disorder and substance abuse, the direction of causality is uncertain. An association is also seen with anxiety disorders, attention-deficit/hyperactivity disorder, and eating disorders, as well as cyclothymia and other axis II personality disorders. Medical disorders accompany bipolar disorder at rates greater than predicted by chance. However, it is often unclear whether a medical disorder is truly comorbid, a consequence of treatment, or a combination of both. CONCLUSION: To ensure prompt, appropriate intervention while avoiding iatrogenic complications, the clinician must evaluate and monitor patients with bipolar disorder for the presence and the development of comorbid psychiatric and medical conditions. Conversely, physicians should have a high index of suspicion for underlying bipolar disorder when evaluating individuals with other psychiatric diagnoses (not just unipolar depression) that often coexist with bipolar disorder, such as alcohol and substance abuse or anxiety disorders. Anticonvulsants and other mood stabilizers may be especially helpful in treating bipolar disorder with significant comorbidity.

White matter hyperintensity progression and late-life depression outcomes.

CONTEXT: White matter hyperintensities (WMHs) are bright foci seen in the parenchyma of the brain on T2-weighted cranial magnetic resonance imaging (MRI) scans and are associated with geriatric depression. Because they are associated with age, they should increase in number and size over time. To our knowledge, this is the first longitudinal, volumetric MRI study of WMHs in depression. OBJECTIVE: To determine if WMH progression over 2 years influences depression outcomes. DESIGN: Over 2 years, depressed subjects received antidepressant treatment according to a naturalistic somatic treatment algorithm designed to offer the best possible treatment to the individual. After the treatment period, depressed subjects were dichotomized based on whether they had reached and sustained remission during this period. PARTICIPANTS: One hundred thirty-three subjects aged 60 years or older meeting DSM-IV criteria for major depressive disorder. MEASURES: Cranial MRI was obtained at baseline and approximately 2 years later. White matter hyperintensity volume was measured in each hemisphere using a semiautomated segmentation process. OUTCOMES: Subjects were dichotomized based on achieving or not achieving remission of depressive symptoms, defined as a Montgomery-Asberg Depression Rating Scale score of 8 or less. RESULTS: The depressed subgroup that achieved and sustained remission had significantly less increases in WMH volume (11.5%) than did the group that did not achieve or sustain remission (31.6%) (P =.01). In a regression model, greater change in WMH volume was significantly associated with failure to sustain remission (P =.004) even when controlling for baseline depression severity, medical illness severity, age, sex, and race. Education was associated with achieving and sustaining remission (P =.02). CONCLUSIONS: Greater progression of WMH volume is associated with poor outcomes in geriatric depression. Future work is needed to develop means of slowing the rate of WMH progression and to determine whether this will lead to improved depression outcomes in elderly persons.

A pilot randomized controlled trial using EEG-based brain-computer interface training for a Chinese-speaking group of healthy elderly.

BACKGROUND: There is growing evidence that cognitive training (CT) can improve the cognitive functioning of the elderly. CT may be influenced by cultural and linguistic factors, but research examining CT programs has mostly been conducted on Western populations. We have developed an innovative electroencephalography (EEG)-based brain-computer interface (BCI) CT program that has shown preliminary efficacy in improving cognition in 32 healthy English-speaking elderly adults in Singapore. In this second pilot trial, we examine the acceptability, safety, and preliminary efficacy of our BCI CT program in healthy Chinese-speaking Singaporean elderly. METHODS: Thirty-nine elderly participants were randomized into intervention (n=21) and wait-list control (n=18) arms. Intervention consisted of 24 half-hour sessions with our BCI-based CT training system to be completed in 8 weeks; the control arm received the same intervention after an initial 8-week waiting period. At the end of the training, a usability and acceptability questionnaire was administered. Efficacy was measured using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), which was translated and culturally adapted for the Chinese-speaking local population. Users were asked about any adverse events experienced after each session as a safety measure. RESULTS: The training was deemed easily usable and acceptable by senior users. The median difference in the change scores pre- and post-training of the modified RBANS total score was 8.0 (95% confidence interval [CI]: 0.0-16.0, P=0.042) higher in the intervention arm than waitlist control, while the mean difference was 9.0 (95% CI: 1.7-16.2, P=0.017). Ten (30.3%) participants reported a total of 16 adverse events - all of which were graded "mild" except for one graded "moderate". CONCLUSION: Our BCI training system shows potential in improving cognition in both English- and Chinese-speaking elderly, and deserves further evaluation in a Phase III trial. Overall, participants responded positively on the usability and acceptability questionnaire.

Cerebrovascular disease and evolution of depressive symptoms in the cardiovascular health study.

BACKGROUND AND PURPOSE: Previous studies have reported an association between cerebrovascular disease and depressive symptoms. The Cardiovascular Health Study (CHS) provides an opportunity to examine the relationship between vascular brain pathology seen on neuroimaging and changes in depressive symptoms. METHODS: The sample included 3236 CHS participants who had an MRI brain scan. Demographic variables, medical history, functional status, and apolipoprotein E genotype were obtained at baseline. Annual scores on a modified version of the Centers for Epidemiologic Studies Depression (CES-D) scale were obtained initially and up to 7 years subsequently. RESULTS: After controlling for important covariates, occurrence of depressive symptoms (defined as modified CES-D score of >7) was associated with small lesions in the basal ganglia, large cortical white-matter lesions, and severe subcortical white-matter grade. Neuroimaging variables did not predict incident depression among those who were nondepressive at the time of MRI. Persistence of depressive symptoms across 2 consecutive time points was associated with small basal ganglia lesions and large cerebral cortical white-matter lesions. Worsening of depression (increase in CES-D score of > or =5) was associated with subcortical white-matter lesions. CONCLUSIONS: These findings suggest that cerebrovascular disease at baseline is related to depression symptoms over time. Further studies are needed to investigate the differential effects of subcortical white- versus gray-matter lesions on mood.

Comorbidity and depression treatment.

Comorbidity is common among patients with major depression, but in most instances it may be of little relevance. Nonetheless, it is a complex issue because of its relation to treatment response, and few studies have attempted to address this. Most have examined comorbidity after the fact in secondary analyses. In this article, I focus on whether comorbidity influences depression treatment response among patients who are primarily diagnosed as suffering from major depression. At least three comorbidities are believed to influence treatment response: medical, anxiety, and personality disorders. Whether studies find that these factors predict worse outcomes in patients with major depression appears to depend on the nature and severity of the medical illness, the study setting, and the study design. The best designed studies reported the least effects of these factors on treatment outcome. Clinically, this suggests that these factors should not be seen as impediments to treatment.

Diffusion tensor imaging: background, potential, and utility in psychiatric research.

Diffusion tensor imaging is a variation of magnetic resonance imaging that measures the diffusion of water in tissues. This can help measure and quantify a tissue's orientation and structure, making it an ideal tool for examining cerebral white matter and neural fiber tracts. It is only beginning to be utilized in psychiatric research. This article reviews the theory behind diffusion tensor imaging, its potential to map fiber tracts in the brain, and its recent use in psychiatric research.

Focal and lateralized subcortical abnormalities in unipolar major depressive disorder: an automated multivoxel proton magnetic resonance spectroscopy study.

BACKGROUND: The results of prior proton magnetic resonance spectroscopy ((1)H-MRS) studies in unipolar major depressive disorder (MDD) evaluating choline (Cho)/creatine (Cr) and N-acetyl-L-aspartate (NAA)/Cr ratios are mixed. These single-voxel or one-dimensional chemical-shift imaging (CSI) nonautomated (1)H-MRS studies has been unable to evaluate global or lateralized abnormalities in neuronal or membrane function. Using automated multivoxel two-dimensional CSI (1)H-MRS techniques, we tested the hypothesis that patients with MDD have focal neuronal and membrane abnormalities localized in the subcortical region. METHODS: Whole brain and subcortical measures of Cho, NAA, Cr, and myo-inositol (mI) were obtained in 18 patients with MDD and 20 control subjects using automated two-dimensional CSI (1)H-MRS. RESULTS: Compared with control subjects, MDD patients had a significantly lower mean NAA/Cr amplitude in the caudate and a significantly higher mean Cho/Cr amplitude in the putamen, particularly on the right side. No differences were observed for global whole brain measurements. CONCLUSIONS: The findings support reduced neuronal viability or function in the caudate and altered membrane phospholipid metabolism in the putamen for patients with MDD. Our results are consistent with prior magnetic resonance imaging, positron emission tomography, and postmortem reports of focal and lateralized abnormalities of the basal ganglia in MDD.

Smaller orbital frontal cortex volumes associated with functional disability in depressed elders.

BACKGROUND: Depression is associated with significant functional impairment. Recent evidence has linked the orbital frontal cortex (OFC) with depression. We examined the relationship between OFC volumes in older subjects and impairment in the basic (BADL) and instrumental (IADL) activities of daily living. METHODS: The sample consisted of 81 subjects aged 60 years or older; 41 were depressed subjects and 40 healthy control subjects. In a structured interview, subjects reported their medical history and ability to perform both BADL and IADL. Subjects then had a brain magnetic resonance imaging (MRI) scan; the OFC was manually traced bilaterally using neuroanatomical landmarks. Logistic regression was used to examine the effect of OFC volume on BADL and IADL while controlling for the effects of total brain volume, subject status, medical comorbidity, and demographic factors. RESULTS: Smaller OFC volumes, along with greater cognitive impairment as measured by the Mini-Mental State Examination, were significantly associated with BADL impairment. Smaller OFC volumes and being depressed were significantly associated with IADL impairment. CONCLUSIONS: Smaller OFC volumes are independently associated with functional impairment, supporting its role in depression. Further studies are needed to determine how smaller OFC volumes are related to other MRI abnormalities associated with depression and functional impairment.

Clinical characteristics of magnetic resonance imaging-defined subcortical ischemic depression.

BACKGROUND: There is a substantial body of research supporting the vascular depression hypothesis of late-life depression. To update this hypothesis so it incorporates recent research, we propose that the term subcortical ischemic vascular depression may be a more accurate representation of the disease process. We sought to investigate this diagnosis as a construct by examining differences between depressed subjects with and without magnetic resonance imaging defined subcortical ischemic vascular depression. METHODS: This case-control study examined 139 depressed elderly subjects. Demographic data, psychiatric, medical, and family history, depressive symptomatology, and functional impairment were compared between groups dichotomized based on neuroimaging findings. RESULTS: Seventy-five (54%) of the subjects met neuroimaging criteria for subcortical ischemic vascular depression. Age was most strongly associated with increased prevalence of subcortical ischemic vascular depression. Lassitude and a history of hypertension were also positively associated with the diagnosis; a family history of mental illness and loss of libido were negatively associated with the diagnosis. CONCLUSIONS: These data support that subcortical ischemic vascular depression may be a specific syndrome from other types of late-life depression. Further research is needed to further characterize this disorder, particularly in regards to cognitive function and treatment implications.

Predicting suicidal risk in schizophrenic and schizoaffective patients in a prospective two-year trial.

BACKGROUND: Enhanced ability to reliably identify risk factors for suicidal behavior permits more focused decisions concerning treatment interventions and support services, with potential reduction in lives lost to suicide. METHODS: This study followed 980 patients at high risk for suicide in a multicenter prospective study for 2 years after randomization to clozapine or olanzapine. A priori predictors related to diagnosis, treatment resistance, and clinical constructs of disease symptoms were evaluated as possible predictors of subsequent suicide-related events. RESULTS: Ten baseline univariate predictors were identified. Historical predictors were diagnosis of schizoaffective disorder, history or current use at baseline of alcohol or substance abuse, cigarette smoking, number of lifetime suicide attempts, and the number of hospitalizations in the previous 36 months to prevent suicide. Predictive clinical features included greater baseline scores on the InterSePT scale for suicidal thinking, the Covi Anxiety Scale, the Calgary Depression Scale (CDS), and severity of Parkinsonism. Subsequent multivariate analysis revealed the number of hospitalizations in the previous 36 months, baseline CDS, severity of Parkinson's, history of substance abuse, and lifetime suicide attempts. Clozapine, in general, was more effective than olanzapine in decreasing the risk of suicidality, regardless of risk factors present. CONCLUSIONS: This is the first prospective analysis of predictors of suicide risk in a large schizophrenic and schizoaffective population judged to be at high risk for suicide. Assessment of these risk factors may aid clinicians in evaluating risk for suicidal behaviors so that appropriate interventions can be made.

Subcortical lesion severity and orbitofrontal cortex volume in geriatric depression.

Previous studies have shown a reduction of orbital frontal cortex volume and an increase in magnetic resonance imaging signal hyperintensities in geriatric depression. We aimed to assess the relationship between subcortical gray- and deep white-matter lesions and orbital frontal cortex volume in elderly depressives and controls. The study included 41 elderly depressed patients and 41 age-matched control subjects. The orbital frontal cortex volume was measured in both hemispheres using a standardized MRI procedure. Signal hyperintensities were rated on (T2)-weighted MRI with qualitative lesion analyses performed according to an established hyperintensity classification system. After controlling for total cerebral hemisphere, age and sex, the geriatric depressed subjects had significant reduction in orbital frontal cortex volume and compared with the control group. Multiple linear regression modeling indicated that reduced orbital frontal cortex volumes were significantly associated with increased subcortical gray-matter lesions. Our study confirmed the reduction of OFC volume in geriatric depressed subjects. We also suggest that subcortical lesions may decrease OFC volume. Further studies are needed to understand how subcortical lesions may be related to OFC volume changes.

Research design features and patient characteristics associated with the outcome of antidepressant clinical trials.

OBJECTIVE: The authors examined which, if any, research design features and patient characteristics would significantly differ between successful and unsuccessful antidepressant trials. METHOD: Clinical trial data were reviewed for nine antidepressants approved by the Food and Drug Administration between 1985 and 2000. From the antidepressant research programs on these medications, 52 clinical trials were included in the study. The authors evaluated trial design features, patient characteristics, and difference in response between placebo and antidepressant. RESULTS: Nine trial design features and patient characteristics were present in the research programs for all nine of the antidepressants. The severity of depressive symptoms before patient randomization, the dosing schedule (flexible versus fixed), the number of treatment arms, and the percentage of female patients were significantly associated with the difference in response to antidepressant and placebo. The duration of the antidepressant trial, number of patients per treatment arm, number of sites, and mean age of the patients were similar in successful trials (with a greater antidepressant-placebo difference) and less successful trials (with a smaller antidepressant-placebo difference). CONCLUSIONS: These findings may help in the design of future antidepressant trials.

Antidepressant pharmacotherapy in the treatment of depression in the very old: a randomized, placebo-controlled trial.

OBJECTIVE: This study determined the efficacy of antidepressant medication for the treatment of depression in the "old-old." METHOD: This randomized 8-week medication trial compared citalopram, 10-40 mg/day, to placebo in the treatment of patients 75 and older with unipolar depression. RESULTS: A total of 174 patients who were 58% women with a mean age of 79.6 years (SD=4.4) and a mean baseline Hamilton Depression Rating Scale score of 24.3 (SD=4.1) were randomly assigned to treatment at 15 sites. There was a main effect for site but not for treatment condition. The remission rate, defined as a final Hamilton depression scale score <10, was 35% for the citalopram and 33% for the placebo groups. However, patients with severe depression (baseline Hamilton depression scale score >24) tended to have a higher remission rate with medication than with placebo (35% versus 19%). CONCLUSIONS: In the oldest group of community-dwelling patients to be studied to date, medication was not more effective than placebo for the treatment of depression. However, given the considerable psychosocial support received by all patients, the placebo condition represents more than the ingestion of an inactive pill. Across sites, there was considerable range in response to medication, 18% to 82%, and to placebo, 16% to 80%.

Late-life depression and microstructural abnormalities in dorsolateral prefrontal cortex white matter.

OBJECTIVE: The purpose of this study was to determine whether microstructural abnormalities in the white matter of the dorsolateral prefrontal cortex are associated with late-life depression. METHOD: Seventeen elderly depressed subjects were compared with 16 elderly subjects who were not depressed. Diffusion tensor imaging was used to measure the fractional anisotropy of the white matter in the dorsolateral prefrontal cortex's superior and middle frontal gyri bilaterally and in the left occipital lobe as a control region. The authors compared results between groups while controlling for age, sex, and comorbid medical disorders. RESULTS: Even after controlling for age, sex, hypertension, and heart disease, the authors found significantly lower fractional anisotropy values in the right superior frontal gyrus white matter of depressed patients than comparison subjects. CONCLUSIONS: Microstructural changes in the white matter of the right superior frontal gyrus are associated with late-life depression. Further work is needed to determine how these changes contribute to depression outcomes.