Background
Neuroticism and extraversion are affected by depressive disorder state. Less is known about depressive state effects on conscientiousness, agreeableness and openness. Furthermore, state effects of anxiety disorders on personality have been far less studied than those of depressive disorder. Here, we aim to determine the extent of change in all five personality traits associated with the occurrence of or recovery from depressive and anxiety disorders.
Methods
Using the Composite International Diagnostic Interview (CIDI) at baseline and two-year follow-up, respondents from the Netherlands Study of Depression and Anxiety (NESDA) were divided into four groups: unaffected at baseline and follow-up, occurrence, recovery, and affected at baseline and follow-up. Personality change (NEO-five factor inventory) was examined in the occurrence and recovery groups relative to the unaffected and affected groups, respectively. Analyses were repeated, differentiating between (specific) depressive and anxiety disorders.
Results
We found small state effects of affective disorders on neuroticism, extraversion and conscientiousness. Corrected for each other, both depressive and anxiety disorders showed small state effects on neuroticism, but effects on extraversion and conscientiousness were mainly associated with depressive disorders.
Conclusions
State effects were small. When assessing neuroticism, the presence of both depressive and anxiety disorders should be taken into account, as both may independently increase neuroticism scores. However, when assessing extraversion and conscientiousness, depressive disorders but not anxiety disorders are likely to be of influence. Agreeableness and openness are influenced by neither.
The stability of personality traits has been subject to debate. One of the most prominent personality models is the Five-Factor Model of Personality (McCrae and Costa, 1996), which distinguishes five higher order traits: neuroticism, extraversion, conscientiousness, agreeableness and openness. Originally these traits were assumed to be exclusively biological in origin, to be unaffected by effects of the environment, and to mature until early adulthood and from then on to remain stable over time (McCrae and Costa, 1999 and Terracciano et al., 2010). However, there is some evidence that personality traits are susceptible to gradual change over time (Srivastava et al., 2003 and Roberts et al., 2006), or, as shown recently, when suffering from a depressive episode (Costa et al., 2005).
Indeed, studies have found neuroticism to increase and extraversion to decrease during depressive episodes, either temporarily (the state effect; Griens et al., 2002 and Ormel et al., 2004), or even permanently in some (the scar effect; Kendler et al., 1993), but not all (Shea et al., 1996, Ormel et al., 2004 and Jylhä et al., 2009) studies. While most studies focused on change in neuroticism (Ormel et al., 2004) and sometimes change in extraversion (Jylhä et al., 2009), less is known about changes in conscientiousness, agreeableness, or openness, although some studies have found them to be stable during a depressive episode (Harkness et al., 2002, Malouff et al., 2005 and Morey et al., 2010). Also, compared to depression, change in personality in association with occurrence of or recovery from anxiety disorders has been far less studied (Bienvenu and Brandes, 2005). There is limited evidence that neuroticism decreases and extraversion increases when anxiety symptoms ameliorate in patients with panic disorder and agoraphobia (Reich et al., 1986) as well as in patients with depressive disorder (Jylhä et al., 2009). Rarely have depressive and anxiety disorders been studied together in their association with change in personality. However, depressive and anxiety disorders often co-occur, therefore, the association of either depressive disorders or anxiety disorders with change in personality may be confounded by the other when studied separately.
In order to study the association of change in personality trait scores with change in depressive and anxiety disorders, longitudinal within subject designs are needed. In this study using baseline and 2-year follow-up data from a large longitudinal cohort study, we will investigate the association of change in personality trait scores with the onset of and the recovery from depressive and anxiety disorders, known as the state effect. The aim of our study is to determine the extent of change in all five personality traits associated with the occurrence of or recovery from depressive and anxiety disorders. Based on the existing literature, we expect the change in neuroticism and extraversion trait scores to be associated with the occurrence of and recovery from both depressive and anxiety disorders.
