The link between addiction and personality disorders more generally but now it’s time to get specific, read on for an in-depth look at the science behind the link between Cluster A personality disorders and substance abuse problems. A personality disorder is a mental health condition that affects the way a person thinks, feels and behaves making it difficult to deal with emotions and interact in appropriate ways with others.

Cluster A personality disorders are characterised by peculiar and eccentric ways of thinking and being that appear strange to others. They include paranoid personality disorder, schizoid personality disorder and schizotypal personality disorder. The common traits in this cluster are social awkwardness and social withdrawal.

Cluster A personality disorders and substance abuse problems

The science behind the three Cluster A personality disorders and addiction

Paranoid personality disorder

Paranoid personality disorder is characterised by:

  • A strong distrust and suspicion of other and their motives
  • An unjustified belief that others are trying to harm and deceive you
  • An unjustified suspicion of the loyalty and trustworthiness of others
  • A hesitancy to confide in others due to unreasonable fear that other will use the information against you
  • A perception of innocent remarks or nonthreatening situations as personal insults or attacks
  • An angry reaction to perceived insults
  • A tendency to hold grudges
  • An unjustified repeated suspicion that your sexual partner is being unfaithful

Research on paranoid personality disorder has suggested the condition is associated with childhood trauma and social stress.

Those with paranoid personality disorder have an increased risk of the development of other disorders: Up to 75% or people with this condition had at least one other personality disorder as well. This research also found a “frequent overlap” with this disorder and substance abuse.

A study on outpatients of an addiction treatment programme found that 4.4% met the diagnosis of paranoid personality disorder. Other research estimates this figure to be closer to 10%. According to another study, paranoid personality disorder is the third most common personality disorder amongst those with an active alcohol addiction.

Abusing substances in childhood has been found to increase the odds of a later diagnosis with this personality disorder. There are many reasons why a person with this personality disorder may turn to drugs and alcohol.

For people with this disorder, alcohol and other sedative drugs can have a “calming” effect, reducing anger, anxiety and obsessions related to paranoid personality disorder. However, this reprieve from powerful emotions is only temporary and when the drug wears off, these feelings often return stronger than before causing a person to consume more drugs – thus perpetuating a drug use cycle that can turn into an addiction.

Marijuana has also been found to cause or heighten paranoia, therefore using this drug is particularly risky for people with paranoid personality disorder.

It has been notably difficult to get people with paranoid personality disorder into addiction therapy as they are often suspicious of treatment. People with this personality disorder also might refuse to seek medical care for other health issues caused by drugs or alcohol putting them at a higher risk for negative complications from sickness or injury including death.

This suspiciousness could also serve as a barrier to full participation in treatment for those who have agreed to attend a rehabilitative facility.

For these patients, therapists have to work hard to establish trust in order to be able to adequately challenge the client’s problematic beliefs and thought patterns. Clients need to be given the tools to engage in new ways of thinking and behaving so that they don’t return to old coping mechanisms such as substance abuse.

Schizoid personality disorder

Schizoid personality disorder is characterised by:

  • A lack of interest in social or personal relationships and preferring to be alone
  • A limited range of emotional expression
  • An inability to experience pleasure from most activities
  • An inability to pick up on normal social cues
  • An appearance of being cold or indifferent to others
  • Little or no interest in having sex with another person
  • A feeling of emptiness

Although they may seem similar, schizoid personality disorder is not the same as schizophrenia. Those with this disorder are more detached from relationships than from reality. Drug abuse amongst those with schizoid personality disorder is relatively high and is thought to be related to efforts deal with symptoms by self-medicating. In people with this disorder, marijuana use is thought to give users temporary relief from feelings of emptiness. Stimulant use appears to counteract low energy levels in people with schizoid personality disorder.

Addiction does not seem to be directly related to schizoid personality disorder. However, anxiety and depression related to this personality disorder does raise the risk of developing an addiction.Another theory is that those with this disorder may use substances as a substitute for personal relationships.

Drug abuse can mimic characteristics of schizoid personality disorder requiring a skilled psychiatrist to make a diagnosis and for patients to be followed up to check if symptoms resolve after abstinence from drugs or alcohol. On the other hand, schizoid personality disorder traits may be masked by substance use: This also means a skilled psychiatrist should be available to identify and diagnose this disorder once a person stops using substance and enters addiction treatment.

People with this disorder may be reluctant to seek treatment because therapy means they will need to interact with other people.

Schizotypal personality disorder

This disorder is marked by:

  • Strange or peculiar dress, thinking, beliefs, speech or behaviour
  • Odd perceptual experiences, for example hearing a voice whisper your name
  • Flat emotions or inappropriate emotional responses
  • Social anxiety and discomfort with close relationships
  • A feeling of alienation
  • Indifferent, inappropriate or suspicious response to others
  • “Magical thinking” i.e., believing you can influence people and events with your thoughts
  • A belief that certain casual incidents or events have hidden messages only for you

According to a study on personality disorders amongst people seeking treatment for addiction, schizotypal personality disorder, along with antisocial and borderline personality disorder, was more “consistently associated with persistent alcohol, cannabis and nicotine use disorders at 3-year follow-up as compared to other [personality disorders]”.

It is thought that the reason people with this disorder turn to substances is to self-medicate feelings of anxiety and alienation.Substance abuse has been found to increase the symptoms of schizotypal personality disorder, specifically odd behaviours and strange thought patterns. Substance abuse may decrease anxiety in the short term for people with this disorder, but often heightens anxiety in the long-term.

People who have been diagnosed with this personality disorder may find it more difficult to stay sober after addiction treatment which is why it is important that the co-occurring disorder is appropriately treated during and after rehab. An in-depth explanation of the relationship between Cluster A personality disorders (paranoid, schizoid and schizotypal personality disorder) and addiction – according to the science.

Treating the personality disorder at the same time as the addiction, and continuing therapy after rehab, has been found to increase the odds of long-term sobriety as well improve an affected person’s quality of life. Are you looking for addiction treatment that uses a dual diagnosis approach? Contact us today.

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