Causes & Effects of Delusional Disorder

At Covington Behavioral Health, we believe education is an important first step in the effort to heal from delusional disorders. Understanding the signs, symptoms, and effects of delusional disorders can help you get the right type and level of care for yourself or a loved one.

Understanding Delusional Disorder

Learn about delusional disorders

Although a person with delusional disorder may be able to work and lead a fairly normal life, there will be some observable peculiarities in his or her manner of thinking. Certain beliefs that he or she holds will be completely irrational and held as fact even though all evidence points to the belief being incorrect.

There are different forms of delusions. Jealous delusions make a person believe that his or her mate has been unfaithful, while erotomanic delusions involve the belief that another person (or persons) is in love with the individual despite convincing evidence that that is not the case. Persecutory delusions cause fear of being attacked or plotted against, and grandiose delusions cause an individual to believe that he or she is extremely praiseworthy and special. Somatic delusions have to do with body sensations, such as feelings that bugs live underneath a person’s skin, or that he or she perpetually smells bad.

Usually, a person’s delusional thinking only comes to the fore when the topic of his or her irrational belief is being considered. When discussing other subjects, his or her thinking can be quite rational. Fortunately, those who are suffering from delusional disorders can receive treatment and experience the healing they deserve.


Delusional disorders statistics

Delusional disorder affects 0.2 percent of people at some point in their lives, according to the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders. Neither men nor women are at greater risk for delusional thinking in general, with the exception that men tend to have the jealous type of delusion.

Causes and Risk Factors

Causes and risk factors for delusional disorders

Genetic: Schizotypal personality disorder and schizophrenia disorder are genetically linked to delusional personality disorder. The presence of a family member with schizophrenia or schizotypal personality disorder in the family increases one’s risk of developing delusional disorder.

Risk Factors:

  • Having increased age
  • Family history of schizophrenia or schizotypal personality disorder

Signs and Symptoms

Signs and symptoms of delusional disorders

Each case is unique, as two different people can have two different symptoms and experiences with delusional disorder. The following list shows common symptoms of this disorder:

Behavioral symptoms:

  • Demonstrations of aggression towards others (especially those associated with the delusional belief)
  • Acting in an antagonistic manner, such as filing lawsuits
  • Strange behaviors, such as constant scratching
  • Poor performance at work
  • Ability to operate normally when delusional areas are not involved

Cognitive symptoms:

  • Having one or more delusional beliefs
  • Persecutory delusion
  • Erotomanic delusion
  • Grandiose delusion
  • Jealous delusion
  • Somatic delusion
  • Another delusional belief of some unspecified type
  • Normal thinking in other areas

Psychosocial symptoms:

  • Easily agitated
  • Social conflict that results from delusional belief
  • Romantic conflict that results from delusional belief


Effects of delusional disorders

Schizophrenia spectrum and psychotic disorders generally affect a person more deeply than disorders of isolated delusional thoughts. That is not to say, though, that a delusional disorder will not cause extreme difficulty. Each person with delusions will experience negative outcomes in the particular area of life that his or her belief interacts with, such as the following:

  • Harboring a violent or angry attitude toward another person
  • Experiencing conflict in romantic relationships
  • Legal problems
  • Difficulty performing work
  • Job loss
  • Financial struggle
  • Mental disorder onset or intensification
  • Social relationship struggles
  • Self-imposed isolation
  • Self-harm from acting to stop perceived threats
  • Increased irritability

Prior to treatment, my life was not only unmanageable, it was unlivable. Covington Behavioral Health Hospital helped provide me with a full, meaningful life. Thank you!

– a former patient
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