Personality and psychopathology in late life.

Personality structure, defined as an enduring, consistent, and unique set of behavioral traits that differentiates one individual from another, forms the foundation of a person's response to both normal and pathologic aging. Although normal aging of the brain may not greatly influence personality, brain injury and disease often lead to personality change. Overall personality traits have been found to be stable within cohorts over time, although with several discrete changes. An older individual's responses to age-related stress will depend on the balance of personality strengths and weaknesses. Severe or multiple stresses in late life may overwhelm an individual's coping skills and lead to personality change. Personality disorders, defined as enduring and pervasive patterns of maladaptive behaviors, are challenging to diagnose in late life and have a variable course depending on the type of personality disorder or disorders. More research is needed to improve diagnosis and better understand the manifestations of late-life personality disorders.