Personality traits such as neuroticism and introversion are significant predictors of depression across the lifespan, a study published in the Journal of the American Psychiatric Association has found. Journal of Affective Disorders.
Depression remains one of the leading causes of disability worldwide. Although depression is often characterized by a range of symptoms that vary widely between individuals, one consistent factor appears to be the role of personality traits. Previous studies have established that certain personality traits, such as high neuroticism and low conscientiousness, are associated with an increased risk of both depression and anxiety. However, many studies have focused on only one personality trait at a time or have not considered the possibility that these relationships may change at different stages of life.
Zheng Yang and her colleagues sought to build on this research by examining the relationship between personality traits and symptoms of depression and anxiety across the lifespan.
The researchers used data from the Nathan Kline Institute Rockland Sample (NKI-RS), a large community-based dataset that includes individuals across a range of ages, from adolescents to older adults. The final sample included 1,494 participants, ranging in age from 12 to 85 years old. Participants were divided into four categories: people with depression only, people with anxiety only, people with both depression and anxiety, and a healthy control group with no mental illness.
Participants’ psychiatric diagnoses were determined using structured clinical interviews: the Children’s Schedule for Affective Disorders and Schizophrenia (K-SADS) for participants aged 6–17 years and the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I/NP) for participants aged 18–85 years.
The study assessed personality traits using the NEO Five-Factor Inventory (NEO-FFI), which assesses five major aspects of personality: neuroticism, extraversion, openness to experience, agreeableness, and conscientiousness. The researchers also collected a range of psychological and physical measures, including cognitive tasks, questionnaires about eating behaviors, and physiological assessments such as heart rate monitoring and body mass index (BMI).
We found that people with depression and anxiety had higher neuroticism and lower extraversion than healthy people. This pattern was particularly pronounced for people with comorbid depression and anxiety, who showed the additional vulnerable personality traits of higher neuroticism and higher introversion. During adolescence, depression was associated with higher neuroticism and lower extraversion, agreeableness, and conscientiousness. Meanwhile, adolescent anxiety was associated with higher neuroticism and conscientiousness.
In adulthood, the relationship between personality traits and mental health symptoms appears to change. After controlling for anxiety, depression was no longer significantly associated with any of the personality traits. This suggests that other factors, such as life stress and biological changes, may play a more important role in influencing depression in adults.
However, anxiety is strongly linked to neuroticism and negatively correlated with extraversion, agreeableness, and conscientiousness, suggesting that individuals low in introversion, agreeableness, and conscientiousness are more likely to experience anxiety symptoms in adulthood.
In older adulthood, depression did not correlate significantly with personality traits, but anxiety was associated with neuroticism and, typical of this age group, with agreeableness and openness to experience.
The machine learning model achieved 70% accuracy in predicting depression, with neuroticism and introversion emerging as the most significant predictors of depression. Furthermore, higher BMI, lower heart rate variability during exercise, and certain eating behaviors such as disinhibition and increased hunger were also found to be significant factors contributing to the likelihood of depression. These findings suggest that a combination of personality traits, physical health indicators, and lifestyle behaviors can effectively predict depression risk.
Of note, the cross-sectional design of this study limits the ability to make causal inferences about the relationship between personality traits and depression.
the study, “Personality traits as predictors of depression across the lifespan” was written by Zhen Yang, Allison Li, Chloe Roske, Nolan Alexander, and Vilma Gabbay.
