Paranoia

Paranoid personality disorder is a pattern of pervasive distrust and suspiciousness of others such that their motives are interpreted as malevolent. An inability to trust, doubts about others' loyalty, distortion and fabrication, misinterpretation, and bearing grudges unnecessarily are hallmarks of the disorder. Pathological jealousy, instinctive aggressive counter-attack, the need to control others, and the gathering of trivial or circumstantial "evidence" to support their jealous beliefs also feature.

Paranoia refers to gradually developing, systematized delusional states, without hallucinations or general personality deterioration but with preservation of intelligence, and with emotional responses and behaviour that remain congruous with and appropriate to the persecutory or grandiose delusions.

The term paranoia is one of the oldest in the history of psychiatry. It was used in pre-Hippocratic times and, in ancient Greek literature, is the term for mental derangement. It was reintroduced into medicine in 1764, and was applied to various conditions. In 1883, a New York psychiatrist, E C Spitzka, gave paranoia its present definition.

The DSM-IV Diagnostic Criteria for paranoid personality disorder are: (1) A pervasive distrust and suspiciousness of others such that their motives are interpreted as malevolent as indicated by at least four of: (i) suspects, without sufficient basis, that others are exploiting, harming or deceiving him or her (ii) is preoccupied with unjustified doubts about the loyalty or trustworthiness of friends or associates (iii) is unwilling to confide in others because of unwarranted fear that the information will be used maliciously against him or her (iv) reads hidden demeaning or threatening meanings into benign remarks or events (v) persistently bears grudges, ie is unforgiving of (perceived) insults, injuries or slights (vi) perceives attacks on his or her character or reputation that are not apparent to others and is quick to react angrily or to counter-attack (vii) has recurrent suspicions, without justification, regarding the fidelity of spouse or sexual partner; (2) Does not occur exclusively during a course of schizophrenia, mood disorder, etc.

Paranoid patients are relatively rare in the mental hospital population. They constitute about 0.5% of first admissions and less than 1.5% of resident patients in mental hospitals in the USA. However, these figures probably underestimate the incidence of the illness in the population at large; many patients are able to control the socially disruptive manifestations of their delusions and are never hospitalized; others, especially where the disorder is less severe, are tolerated at home and at work as eccentrics.