Advancing Brain and Body Vascular Imaging in Bipolar Disorder: A Report From the International Society for Bipolar Disorders Vascular Task Force.

OBJECTIVES

The heart-brain nexus is increasingly recognized as important for human health. Nonetheless, integration of this perspective in research and treatment remains limited in psychiatry, particularly in bipolar disorder (BD). Multisystem vascular imaging may help elucidate mechanisms linking heart and brain health in BD. The ultimate purpose of this review is to inspire and guide integration of vascular imaging more broadly in BD research.

METHODS

An international group of experts reviewed the vascular imaging literature in BD, synthesizing key studies, limitations, and future directions. Findings were organized by organ system (brain, eye, heart, body), including novel methods reported in other psychiatric or neurological disorders that are understudied in BD.

RESULTS

Structural and functional vascular differences, reflecting macro- and microvascular health, are reported across the lifespan in BD. State effects are more apparent for functional than structural metrics. BD-related differences in vascular metrics were independent of traditional vascular risk factors in some but not all studies. Accessibility ranged from widespread (e.g., tonometry, retinal imaging) to specialized (e.g., cardiac magnetic resonance imaging [MRI], arterial-spin labeling MRI). Although small BD samples were common, general population cohorts demonstrate feasibility for broader use.

CONCLUSIONS

BD-related differences in vascular imaging metrics are evident within and beyond the brain. Continued progress is warranted to realize potential implications for brain, heart, and mental health. Larger studies, powered for subgroup analyses and robust covariate modeling, are warranted. Future studies including prospective designs, fluid biomarkers, and lived-experience perspectives would further enhance the relevance of vascular imaging for those with BD.