Clinical, genetic, and brain imaging predictors of risk for bipolar disorder in high-risk individuals

ABSTRACT

Introduction: Early detection and intervention in bipolar disorder (BD) might reduce illness severity, slow its progression, and, in specific cases, even ward off the full-blown disorder. Therefore, identifying at-risk individuals and targeting them promptly before the illness onset is of the utmost importance. In the last decades, there has been a significant effort aimed at identifying genetic and molecular factors able to modulate risk and pharmacological outcomes.

Areas covered: We performed a narrative review of articles aimed at identifying clinical, genetics, molecular, and brain imaging markers of BD specifically focusing on samples of individuals at high-risk for BD. Special emphasis was put on studies applying an integrative design, e.g. studies combining different markers such as genetic and brain imaging.

Expert opinion: Findings from studies in risk individuals are still too sparse to allow drawing definite conclusions. However, the high potentiality of longitudinal studies in individuals considered at risk to develop BD supports the need for more efforts. Future investigations should focus on more homogeneous subpopulations and evaluate the cross-linking between clinical, genetic, and brain morphostructural/functional neuroimaging characteristics as predictors of risk for BD.

KEYWORDS:

• Biomarker
• early intervention
• genetics
• longitudinal
• mood disorders
• neuroimaging
• offspring
• staging
• ultra-high risk

Article highlights

• Due to the genetic and phenotypic heterogeneity of bipolar disorder, specific biomarkers are still lacking

• Additional efforts are necessary to delineate a concrete pattern specific for the onset of bipolar disorder, rather than with unspecific features of other psychiatric disorders

• Multicenter, large sample-size longitudinal studies exploring potential differences occurring among homogeneous subpopulations of at-risk individuals are urgently needed.

Declaration of interest

Claudia Pisanu was supported by a fellowship funded by Fondazione Umberto Veronesi. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewers Disclosure

Peer reviewers on this manuscript have no relevant financial relationships or otherwise to disclose.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

CP was funded by Fondazione Umberto Veronesi.