Grandiose delusions (GD) or delusions of grandeur is principally a subtype of delusional disorder that occurs in patients suffering from a wide range of mental illnesses, including two-thirds of patients in manic state of bipolar disorder, half of those with schizophrenia and a substantial portion of those with substance abuse disorders. GDs are characterized by fantastical beliefs that one is famous, omnipotent, wealthy, or otherwise very powerful. The delusions are generally fantastic and typically have a supernatural, science-fictional, or religious theme. There is a relative lack of research into GD, in comparison to persecutory delusions and auditory hallucinations. About 10% of healthy people experience grandiose thoughts but do not meet full criteria for a diagnosis of GD.

Prevalence

Research suggests that the severity of the delusions of grandeur is directly related to a higher self-esteem in individuals and inversely related to any individual’s severity of depression and negative self-evaluations. Lucas et al. found that there is no significant gender difference in the establishment of grandiose delusion. However, there is a claim that ‘the particular component of Grandiose delusion’ may be variable across both genders. Also, it had been noted that the presence of GDs in people with at least grammar or high school education was greater than lesser educated persons. Similarly, the presence of grandiose delusions in individuals who are the eldest is greater than in individuals who are the youngest of their siblings.

Symptoms

According to the DSM-IV-TR diagnostic criteria for delusional disorder, grandiose-type symptoms include grossly exaggerated belief of:

  • self-worth
  • power
  • knowledge
  • identity
  • exceptional relationship to a divinity or famous person.

For example, a patient who has fictitious beliefs about his or her power or authority may believe himself or herself to be a ruling monarch who deserves to be treated like royalty. There are substantial differences in the degree of grandiosity linked with grandiose delusions in different patients. Some patients believe they are God, the Queen of England, a president’s son, a famous rock star, and so on. Others are not as expansive and think they are skilled sports-persons or great inventors.

Expansive delusions

Expansive delusions may be maintained by auditory hallucinations, which advise the patient that they are significant, or confabulations, when, for example, the patient gives a thorough description of their coronation or marriage to the king. Grandiose and expansive delusions may also be part of fantastic hallucinosis in which all forms of hallucinations occur.

Positive functions

Grandiose delusions frequently serve a very positive function for the person of sustaining or increasing their self-esteem. As a result, it is important to consider what the consequences of removing the grandiose delusion are on self-esteem when trying to modify the grandiose delusion in therapy. In many instances of grandiosity it is suitable to go for a fractional rather than a total modification, which permits those elements of the delusion that are central for self-esteem to be preserved. For example, a man who believes he is a senior secret service agent gains a great sense of self-esteem and purpose from this belief, thus until this sense of self-esteem can be provided from elsewhere, it is best not to attempt modification.