Grandiose delusions

Grandiose delusions (GDs), also known as delusions of grandeur or expansive delusions, are a subtype of delusion characterized by extraordinary belief that one is famous, omnipotent, wealthy, or otherwise very powerful. Grandiose delusions often have a religious, science fictional, or supernatural theme. Examples include the extraordinary belief that one is a deity or celebrity, or that one possesses extraordinary talents, accomplishments, or superpowers.

While non-delusional grandiose beliefs are somewhat common—occurring in at least 10% of the general population—and often positively influence a person's self-esteem, in some cases they may cause a person distress, in which case such beliefs may be clinically evaluated and diagnosed as a psychiatric disorder.

When studied as a psychiatric disorder in clinical settings, grandiose delusions have been found to commonly occur with other disorders, including in two-thirds of patients in a manic state of bipolar disorder, half of those with schizophrenia, patients with the grandiose subtype of delusional disorder, frequently as a comorbid condition in narcissistic personality disorder, and a substantial portion of those with substance abuse disorders.

The term grandiose delusion overlaps with, but is distinct from, grandiosity. Grandiosity is an attitude of extraordinary self-regard (feelings of superiority, uniqueness, importance or invulnerability), while grandiose delusion concerns specific extraordinary factual beliefs about one's fame, wealth, powers, or religious and historical relevance.