Progressive grey matter alterations in bipolar disorder across the life span – A systematic review

Abstract

ObjectivesTo elucidate the relationship between the course of bipolar disorder (BD) and structural brain changes across the life span, we conducted a systematic review of longitudinal imaging studies in adolescent and adult BD patients.MethodsEleven studies with 329 BD patients and 277 controls met our PICOS criteria (participants, intervention, comparison, outcome and study design): BD diagnosis based on DSM criteria, natural course of disease, comparison of grey matter changes in BD individuals over ≥1‐year interval between scans.ResultsThe selected studies yielded heterogeneous findings, partly due to varying patient characteristics, data acquisition and statistical models. Mood episodes were associated with greater grey matter loss in frontal brain regions over time. Brain volume decreased or remained stable in adolescent patients, whereas it increased in healthy adolescents. Adult BD patients showed increased cortical thinning and brain structural decline. In particular, disease onset in adolescence was associated with amygdala volume reduction, which was not reported in adult BD.ConclusionsThe evidence collected suggests that the progression of BD impairs adolescent brain development and accelerates structural brain decline across the lifespan. Age‐specific changes in amygdala volume in adolescent BD suggest that reduced amygdala volume is a correlate of early onset BD. Clarifying the role of BD in brain development across the lifespan promises a deeper understanding of the progression of BD patients through different developmental episodes.

Innovative Neuroimaging Biomarker Distinction of Major Depressive Disorder and Bipolar Disorder through Structural Connectome Analysis and Machine Learning Models

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Short-term ketamine use in bipolar depression: a review of the evidence for short-term treatment management

“…The principal evidence supporting the biological underpinnings of clinical staging in psychiatric disorders points to persistent inflammation and neuroanatomical alterations that may precipitate cognitive decline. Additional biological mechanisms, including modifications in telomere length indicative of DNA changes and various cellular activities, are also implicated in this context (62,63). Evidence suggests that ketamine administration may result in enhanced dendritic spine Consequently, the concept of "downstaging" in TRD has been proposed, which could be applicable to bipolar disorder as well, given its progressive nature (64).…”

Association of hospitalization with structural brain alterations in patients with affective disorders over nine years

“…However, only prospective studies allow to approximate causal conclusions about the relationship between structural brain changes and the course of disease. Unfortunately, only very few longitudinal studies focused on the interplay of gray matter changes and the course of disease [18][19][20]. These studies revealed greater brain volume loss in PAD compared to healthy control participants (HC), in particular in temporo-limbic areas such as the hippocampus and insula as well as parts of the frontal cortex (e.g., dlPFC) [21][22][23][24].…”