Nationwide study results indicated low social maturity, mental energy and emotional stability in late adolescence were associated with subsequent psychiatric disorders among men.

“Kraepelin first raised the question of whether specific premorbid personality traits reflect an early stage of illness or a genetic disposition to serious mental illness. However, our understanding of personality as an independent risk factor for [serious mental illness] remains limited,” Joseph F. Hayes, MB, ChB, MSc, of University College London, and colleagues wrote. “Recently, a polygenic basis for neuroticism and a shared genetic architecture with schizophrenia has been found, with inconsistent results for bipolar disorder. Furthermore, polygenic risk scores for bipolar disorder are associated with extraversion. This research has prompted renewed interest in the association between personality and [serious mental illness].”