Delusional disorder Health Article

Delusion and other disorders

Even though the main characteristic of delusional disorder is a noticeable system of delusional beliefs, delusions may occur in the course of a large number of other psychiatric disorders. Delusions are often observed in persons with other psychotic disorders such as schizophrenia and schizoaffective disorder. In addition to occurring in the psychotic disorders, delusions also may be evident as part of a response to physical, medical conditions (such as braininjury or brain tumors), or reactions to ingestion of a drug.

Delusions also occur in the dementias, which are syndromes wherein psychiatric symptoms and memory loss result from deterioration of brain tissue. Because delusions can be shown as part of many illnesses, the diagnosisof delusional disorder is partially conducted by process of elimination. If the delusions are not accompanied by persistent, recurring hallucinations, then schizophrenia and schizoaffective disorder are not appropriate diagnoses. If the delusions are not accompanied by memory loss, then dementiais ruled out. If there is no physical illness or injury or other active biological cause (such as drug ingestion or drug withdrawal), then the delusions cannot be attributed to a general medical problem or drug-related causes. If delusions are the most obvious and pervasive symptom, without hallucinations, medical causation, drug influences or memory loss, then delusional disorder is the most appropriate categorization.

Because delusions occur in many different disorders, some clinician-researchers have argued that there is little usefulness in focusing on what diagnosis the person has been given. Those who ascribe to this view believe it is more important to focus on the symptom of delusional thinking, and find ways to have an effect on delusions, whether they occur in delusional disorder or schizophrenia or schizoaffective disorder. The majority of psychotherapytechniques used in delusional disorder come from symptom-focused (as opposed to diagnosis-focused) researcher-practitioners.

Causes

Because clear identification of delusional disorder has traditionally been challenging, scientists have conducted far less research relating to the disorder than studies for schizophrenia or mood disorders. Still, some theories of causation have developed, which fall into several categories.

GENETIC OR BIOLOGICAL.Close relatives of persons with delusional disorder have increased rates of delusional disorder and paranoid personality traits. They do not have higher rates of schizophrenia, schizoaffective disorder or mood disorder compared to relatives of non-delusional persons. Increased incidence of these psychiatric disorders in individuals closely genetically related to persons with delusional disorder suggest that there is a genetic component to the disorder. Furthermore, a number of studies comparing activity of different regions of the brain in delusional and non-delusional research participants yielded data about differences in the functioning of the brains between members of the two groups. These differences in brain activity suggest that persons neurologically with delusions tend to react as if threatening conditions are consistently present. Non-delusional persons only show such patterns under certain kinds of conditions where the interpretation of being threatened is more accurate. With both brain activity evidence and family heritability evidence, a strong chance exists that there is a biological aspect to delusional disorder.

DYSFUNCTIONAL COGNITIVE PROCESSING.An elaborate term for thinking is "cognitive processing." Delusions may arise from distorted ways people have of explaining life to themselves. The most prominent cognitive problems involve the manner in which delusion sufferers develop conclusions both about other people, and about causation of unusual perceptions or negative events. Studies examining how people with delusions develop theories about reality show that the subjects have ideas which which they tend to reach an inference based on less information than most people use. This "jumping to conclusions" bias can lead to delusional interpretations of ordinary events. For example, developing flu-like symptoms coinciding with the week new neighbors move in might lead to the conclusion, "the new neighbors are poisoning me." The conclusion is drawn without considering alternative explanations—catching an illness from a relative with the flu, that a virus seems to be going around at work, or that the tuna salad from lunch at the deli may have been spoiled. Additional research shows that persons prone to delusions "read" people differently than non-delusional individuals do. Whether they do so more accurately or particularly poorly is a matter of controversy. Delusional persons develop interpretations about how others view them that are distorted. They tend to view life as a continuing series of threatening events. When these two aspects of thought co-occur, a tendency to develop delusions about others wishing to do them harm is likely.

MOTIVATED OR DEFENSIVE DELUSIONS.Some predisposed persons might suffer the onset of an ongoing delusional disorder when coping with life and maintaining high self-esteem becomes a significant challenge. In order to preserve a positive view of oneself, a person views others as the cause of personal difficulties that may occur. This can then become an ingrained pattern of thought.