Objective: Several studies have found reduced hippocampal volume in patients with unipolar depression, but discrepancies exist. The authors performed a systematic review and meta-analysis of volumetric studies of the hippocampus in patients with mood disorders. Method: Studies of hippocampal volume in unipolar and bipolar patients were identified. A meta-analysis of the 12 studies of unipolar depression fulfilling specific criteria was performed. The sample comprised 351 patients and 279 healthy subjects. Results: The studies were highly heterogeneous regarding age and gender distribution, age at onset of the disorder, average number of episodes, and responsiveness to treatment, but the pooled effect size of depression was significant in both hemispheres for the unipolar patients. The weighted average showed a reduction of hippocampal volume of 8% on the left side and 10% on the right side. The causes of the heterogeneity were analyzed, and a meta-regression showed that the total number of depressive episodes was significantly correlated to right but not left hippocampal volume reduction. Conclusions: Hippocampal volume is reduced in patients with unipolar depression, maybe as a consequence of repeated periods of major depressive disorder. Bipolar patients did not seem to show a reduction in hippocampal volume, but this has been much less investigated.

Hippocampal volume and depression: a meta-analysis of MRI studies.

http://directory.umm.ac.id/Data%20Elmu/jurnal/B/Biological%20Psichatry/Vol48.Issue8.2000/6889.pdf

Neuroimaging studies of mood disorders.

Depression is a disorder of the representation and regulation of mood and emotion. The circuitry underlying the representation and regulation of normal emotion and mood is reviewed, including studies at the animal level, human lesion studies, and human brain imaging studies. This corpus of data is used to construct a model of the ways in which affect can become disordered in depression. Research on the prefrontal cortex, anterior cingulate, hippocampus, and amygdala is reviewed and abnormalities in the structure and function of these different regions in depression is considered. The review concludes with proposals for the specific types of processing abnormalities that result from dysfunctions in different parts of this circuitry and offers suggestions for the major themes upon which future research in this area should be focused.

Depression: perspectives from affective neuroscience.

OBJECTIVE: A number of studies have used magnetic resonance imaging to examine volumetric differences in temporal structures in subjects suffering from major depressive disorder. Studies have reported lower hippocampal and amygdala volume, but results have been inconsistent. The authors were interested, therefore, in examining these studies in the aggregate in order to determine whether hippocampal volume is lower in major depressive disorder. They also examined factors that may contribute to the disparate results in the literature. METHOD: A meta-analysis was conducted of studies that used magnetic resonance imaging to assess the volume of the hippocampus and related structures in patients with major depressive disorder. RESULTS: Patients were seen to have lower hippocampal volume relative to comparison subjects, detectable if the hippocampus was measured as a discrete structure. CONCLUSIONS: Although the effect of major depressive disorder on amygdala volume remains to be conclusively established, inclu...

https://ajp.psychiatryonline.org/doi/pdf/10.1176/appi.ajp.161.4.598

Lower Hippocampal Volume in Patients Suffering From Depression: A Meta-Analysis

Background
Although expert opinion has asserted that there is an increased risk of violence in individuals with schizophrenia and other psychoses, there is substantial heterogeneity between studies reporting risk of violence, and uncertainty over the causes of this heterogeneity. We undertook a systematic review of studies that report on associations between violence and schizophrenia and other psychoses. In addition, we conducted a systematic review of investigations that reported on risk of homicide in individuals with schizophrenia and other psychoses.

/pdf/schizophrenia-and-violence-systematic-review-and-meta-22vzciv2t3.pdf

Schizophrenia and Violence: Systematic Review and Meta-Analysis

Background There is little evidence to support possible structural changes in the amygdala and hippocampus of patients with severe depressionMethods Quantitative MRI of the amygdala and hippocampus, as well as proton spectroscopy (MRS) of mesial temporal structures were studied in 34 drug-resistant in-patients with major depression and compared with 17 age-matched controls Volumetric MRI data were normalized for brain sizeResults The volume of the left hippocampus was significantly smaller in the patients compared with the controls Both groups exhibited similar significant hippocampal asymmetry (left smaller than right) The patients, but not the controls, had significant asymmetry of the amygdalar volumes (right smaller than left) No differences were observed between the patients and controls in the T2 relaxation times for the hippocampus and amygdala Mesial temporal lobe MRS revealed a significantly elevated choline/creatine ratio in the patients compared with the controlsConclusions This quantitative MRI study provides support for a possible association between structural and biochemical substrates and severe drug-resistant major depression

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0033291799001567

Quantitative MRI of the hippocampus and amygdala in severe depression.

It has been suggested that schizophrenia and alcoholism are associated with violent behavior. But so far there are no published studies from unselected cohorts quantifying the actual risk associated with schizophrenia both with and without comorbid alcoholism. In this study, an unselected birth cohort (n = 11,017) was prospectively followed to the age of 26, and data on psychiatric disorders and crimes were collected from national registers. The odds ratios for violent offenses and recidivism were calculated for each diagnostic group. Men who abused alcohol and were diagnosed with schizophrenia were 25.2 (95% confidence interval (CI) 6.1-97.5) times more likely to commit violent crimes than mentally healthy men. The risk for nonalcoholic patients with schizophrenia was 3.6 (95% CI 0.9-12.3) and for other psychoses, 7.7 (95% CI 2.2-23.9). None of the patients with schizophrenia who did not abuse alcohol were recidivists (> 2 offenses), but the risk for committing more crimes among alcoholic subjects with schizophrenia was 9.5-fold (95% CI 2.7-30.0). This study suggests that to prevent the crimes being committed by people with schizophrenia, it is important that clinicians watch for comorbid alcohol abuse. Language: en

Schizophrenia, Alcohol Abuse, and Violent Behavior: A 26-Year Followup Study of an Unselected Birth Cohort

Background The epidemiology of suicidal ideation has remained a relatively unstudied area. The aim of this study was to investigate the incidence, prevalence and persistence of and recovery from suicidal ideation in a sample of the Finnish general population. Methods Postal questionnaires including the Beck Depression Inventory (BDI) were mailed to the study subjects (n = 1,593) at baseline and on follow-up after 12 months. The suicidality item of BDI was used to screen suicidal ideation. Results The 12-month incidence (4.6 %) and prevalence of suicidal ideation (14.7 %) were higher in men than in women (3.1 % and 9.2 %, respectively). Sixty-nine per cent of those men and 59 % of those women who had suicidal ideation at baseline continued to have suicidal thoughts on follow-up. Suicidal ideation and the severity of depression associated strongly. Over half of the men and women who had persistent suicidal ideation had not visited any health services for help with psychological distress during the 12-month follow-up period. Daily smoking associated with a decreased probability of recovery from suicidal ideation. Conclusions Suicidal ideation is common and persistent at the population level. Seeking professional help for depression with suicidal tendencies is disproportionately low in relation to the high prevalence of suicidal ideation.

J. Lehtonen

Papers

Quantitative MRI of the hippocampus and amygdala in severe depression.

Schizophrenia, Alcohol Abuse, and Violent Behavior: A 26-Year Followup Study of an Unselected Birth Cohort

Suicidal ideation in the Finnish general population. A 12-month follow-up study.

731 – Schizophrenia, alcohol abuse and violent behaviour: A 26-year follow-up study of an unselected birth cohort

Schizophrenia, alcohol abuse and violent behaviour