On the one hand, an individual may not consider themselves to have a mental health problem, while on the other, community mental health services may view individuals with personality disorders as too complex or difficult, and may directly or indirectly exclude individuals with such diagnoses or associated behaviors. The disruptiveness that people with personality disorders can create in an organisation makes these, arguably, the most challenging conditions to manage. Apart from all these issues, an individual may not consider their personality to be disordered or the cause of problems. This perspective may be caused by the patients ignorance or lack of insight into their own condition, an ego-syntonic perception of the problems with their personality that prevents them from experiencing it as being in conflict with their goals and self-image, or by the simple fact that there is no distinct or objective boundary between normal and abnormal personalities. There is substantial social stigma and discrimination related to the diagnosis. The term personality disorder encompasses a wide range of issues, each with a different level of severity or impairment; thus, personality disorders can require fundamentally different approaches and understandings. To illustrate the scope of the matter, consider that while some disorders or individuals are characterized by continual social withdrawal and the shunning of relationships, others may cause fluctuations in forwardness. The extremes are worse still: at one extreme lie self-harm and self-neglect, while at another extreme some individuals may commit violence and crime.
Abbreviations used: PPD – Paranoid Personality Disorder, SzPD – Schizoid Personality Disorder, StPD – Schizotypal Personality Disorder, ASPD – Antisocial Personality Disorder, BPD – Borderline Personality Disorder, HPD – Histrionic Personality Disorder, NPD – Narcissistic Personality Disorder, AvPD – Avoidant Personality Disorder, DPD – Dependent Personality Disorder, OCPD – Obsessive–Compulsive Personality Disorder, PAPD – Passive–Aggressive Personality Disorder. The disorders in each of the three clusters may share with each other underlying common vulnerability factors involving cognition, affect and impulse control, and behavioral maintenance or inhibition, respectively. But they may also have a spectrum relationship to certain syndromal mental disorders:
Paranoid, schizoid or schizotypal personality disorders may be observed to be premorbid antecedents of delusional disorders or schizophrenia. Borderline personality disorder is seen in association with mood and anxiety disorders, with impulse-control disorders, eating disorders, ADHD, or a substance use disorder. Avoidant personality disorder is seen with social anxiety disorder. Impact on functioning
It is generally assumed that all personality disorders are linked to impaired functioning and a reduced quality of life (QoL) because that is a basic diagnostic requirement. But research shows that this may be true only for some types of personality disorder. In several studies, higher levels of disability and lower QoL were predicted by avoidant, dependent, schizoid, paranoid, schizotypal and antisocial personality disorders. This link is particularly strong for avoidant, schizotypal and borderline PD. However, obsessive–compulsive PD was not related to a reduced QoL or increased impairment.