Are personality disorders linked to personality traits?

Can personality disorders be seen as the extreme end of personality traits (the OCEAN model)?

Short answer: Yes. This is the DSM-5 Alternative Model for Personality Disorders (AMPD).

The DSM-5's AMPD represents a paradigm shift away from the traditional categorical model in favor of a dimensional approach in PD classification

Dimensional systems such as the AMPD were developed based on several important research findings: a) significant heterogeneity exists within specific PDs, such that two individuals who meet criteria for a given PD may have very different clinical presentations; b) there are high levels of comorbidity (and/or overlap) among purportedly distinct PDs

Sharp et al. (2025) https://doi.org/10.1002/wps.21339

• An early study: Personality Disorders and The Five-Factor Model of Personality
• This study replicates an earlier study (IPC or circumplex model by Costa & McCrae, 1990) that suggests personality disorders aren't qualitatively different from normal personality - they can be understood as extreme or maladaptive variants of the same underlying traits.
• Related study: Conceptions of Personality Disorders and Dimensions of Personality

Both use university students, but that has been replicated beyond university students: A Meta-Analytic Review of the Relationships Between the Five-Factor Model and DSM-IV-TR Personality Disorders: A Facet Level Analysis

The DSM AMPD model papers: - 2025: The validity, reliability and clinical utility of the Alternative DSM-5 Model for Personality Disorders (AMPD) according to DSM-5 revision criteria - 2017: Psychological Assessment with the DSM-5 Alternative Model for Personality Disorders: Tradition and Innovation]

And looking at how personality changes from life events: - Life events and personality trait change: A coordinated data analysis, 195,000k individuals - Marriage predicted a decrease in openness - Starting a new job predicted increases in people’s conscientiousness and emotional stability, - OCEAN changes were less pronounced than changes in life satisfaction