Investigating age at onset in bipolar disorder

Investigating age at onset in bipolar disorder

Lay summary

Bipolar Disorder (BD) is an enduring and severe mental health disorder that affects between 1-4% of the population (Merikangas et al., 2011). It is characterised by extreme mood swings which may last several weeks. Individuals with bipolar disorder will experience episodes of depression as well as episodes of mania, where they feel high and overactive and may have trouble eating and sleeping.

A large body of research suggests that developing bipolar disorder at a young age is associated with a poor clinical outcome. For example, individuals who develop the disorder at an early age may experience longer delays to treatment, greater severity of depression, and higher levels of co-occurring illnesses including anxiety and substance abuse (Agnew-Blais & Danese, 2016; Baldessarini et al., 2012; Coryell et al., 2013; Etain et al., 2012; Schürhoff et al., 2000; Joslyn, Hawes, Hunt, & Mitchell, 2016).

Despite this, no known research has investigated which factors may predict the age at which individuals develop bipolar disorder. Therefore, this project will investigate if factors such as a family history of mental illness, traumatic childhood events, abuse, and deprivation are associated with the age at onset of bipolar disorder.

Moreover, it is also not clear why developing bipolar disorder at an early age may lead to worse clinical outcomes. For example, research suggests that childhood abuse predicts both a young age at onset, and a poor clinical course in bipolar disorder (Leverich et al., 2002; Post et al., 2015). However the nature of this relationship has not been investigated. It may be that childhood abuse leads to onset at a young age, during a developmentally critical period. This disruption to typical development may then result in poor long-term outcomes. Alternatively, childhood abuse may be the driving force behind a poor clinical course, regardless of a young age at illness onset. The project will examine this relationship in more detail.

The planned duration of the project is 18 months. This work is novel and has not been investigated in previous research. Therefore, we hope that our results will inform treatment and preventative strategies for bipolar disorder. Uncovering the factors that may contribute to developing bipolar disorder at a young age and influence clinical outcome can help to establish a targeted approach for early intervention.