Psychology

It can be defined as a persistent pattern of inner experience and behavior that is quite different from the individuals cultural expectations, is insidious and inflexible, start at adolescent or early adulthood, is stable for a considerable time, and results in distress or impairment. Personality problem can therefore be said to mean maladaptive pattern of perceiving and reacting to other people and stressful situations. There are ten personality disorders which have been discovered and they are grouped into three clusters (American Psychiatric Association, 2000). 

Pathophysiology
There is a considerably controversy surrounding personality disorders. Traditional schools of thought maintain that these abnormal patterns of behavior are as a result of dysfunctional early environment that hinders development of adaptive patterns of perception, reactions, and defense. Several studies suggests genetic and psychological contributions to the development of signs of these disorders, however, the information on these studies are not consistent and this prevents the authorities form drawing the final conclusion from these facts (Marshall,  Serin, 1997).

Prevalence
The disorder is diagnosed in about 10 -15 of the total US population. It is possible for an individual to have more than one personality disorder. There are several types of personality disorders and they even vary in terms of their prevalence in the population and causes (Costa,  McCrae, 1990). Paranoid personality disorder constitutes 0.5-2.5, schizotypal type 3, antisocial personality disorder affects 3 of men and 1 of women, borderline personality disorder 2, Histrionic 2-3, narcissistic affects less than 1, avoidant personality disorder 0.5-1, and obsessive compulsive personality disorder affects 1. The information regarding the prevalence of personality disorders in other countries is quite unreliable (Millon,  Roger, 1995).

Mortality and morbidity
Patients suffering from personality disorders are quite prone to many psychiatric disorders as compared to the whole population. Mood disorder is likely to affect all individuals suffering from personality disorders. Some psychiatric disorders are more specific to a particular personality disorders and clusters.

In cluster A, paranoid personality disorder as a complication to delusional disorder or obvious schizophrenia. People suffering from personality disorder grouped in this cluster are prone to agoraphobia, depression, obsessive compulsive disorder, and drug abuse. Those with schizoid personality disorder may also develop major depression while those with schizotypal are likely to develop psychotic disorder or delusional disorder. By the time these individuals are being diagnosed with the disorder, 30-50 is found to have major depression, and majority have a history of major depression episode (Young, 1994).

Cluster B contains antisocial personality disorder and individuals suffering from this kind of disorder are prone to anxiety disorder, substance abuse, somatization disorder, and pathological gambling. Borderline personality disorder is associated with risk of substance abuse, eating disorders especially bulimia, and post traumatic stress disorder. People suffering from borderline personality disorder are at risk of suicide while Histrionic personality disorder is associated to somatoform disorders. Narcissistic personality disorder is closely associated to anorexia nervosa, substance abuse, and episodes of depression (American Psychiatric Association, 2000). 

Cluster C has avoidant, dependent, and obsessive compulsive personality disorder. Avoidant personality disorder is associated with anxiety especially social phobia, dependent personality disorder associated with anxiety and adjustment disorders, while obsessive compulsive personality disorder patients are prone to myocardial infarction because of their lifestyles. They may also experience anxiety disorders (Marshall,  Serin, 1997).

The prevalence of these personality disorders also vary with the sex of the patients. In cluster A, schizoid personality disorder is frequently diagnosed in males as compared to females. In cluster B, antisocial personality disorder is 3 times common in men as opposed to women and the reverse in the case with the borderline personality disorder. Narcissistic personality disorder is quite common in male patients. Cluster C has obsessive compulsive personality disorder and it is twice as common in men as compared to females (Costa,  McCrae, 1990).

Personality disorders cannot be diagnosed in children and adolescents because they have not achieved complete development of personality and symptoms may not continue into adulthood.  Because of this fact, diagnosis of personality disorder should only be done at the age of 18 years and above. Criteria for diagnosis of this disorders are closely connected with the behaviors of young and middle adulthood, therefore this criteria is not reliable in adults (Millon,  Roger, 1995).

History
Patients suffering from personality disorders normally experience a series of problems ranging from social relationships and mood changes. These difficulties can be experienced throughout adulthood. Their patterns of perception, thoughts and response are constant and cannot change, however their behavior cannot be predicted. The patterns of behavior are quite different from their cultural expectations. The diagnosis criterion for personality disorder is referred to as DSM-IV-TR. For one to qualify for diagnosis, the symptoms must attain clinically important distress, or difficulties in social, occupational, or other areas of body function which are considered important. The disorder can develop in all settings and it is not restricted to one aspect of activity (Pervin, 1990).

Physical findings
There are no distinct physical findings which are linked with any type of personality disorder. Physical findings may demonstrate findings associated to the consequences and sequel of different personality problems. Patients suffering from disorders grouped in cluster B may have signs of previous suicide attempts or stigma of substance abuse. Substance abuse is a common accompanying problem and may be demonstrated with the physical stigma of alcoholism or drug abuse. Suicide attempts may be known through scars from self inflicted wounds (Millon,  Roger, 1995).

Mental status may be used to diagnose personality disorder. Patients suffering from histrionic personality may demonstrate la belle indifference, while describing dramatic physical symptoms. Anti social disorder patients have hostile attitude and in some situations, they may become homicidal. Those individuals with borderline personality disorder most of the time display effective liability while paranoid personality disorder patients voice persecutory ideation without the formal thought disorder which is always found in schizophrenia (Marshall,  Serin, 1997).

Although hallucinations are not common, patients with borderline personality disorder may experience dissociative phenomena as though they are hallucinating. In schizotypal disorder, patients speak with peculiar or idiosyncratic use of language. Cognitive functions including memory, orientation, and intelligence are usually affected. Insight is mostly limited as patients link their suffering to uncontrollable influences outside themselves. Judgment can be based on presenting conditions.

Causes of personality disorders
Paranoid personality disorder can attributed to genetic link because of its relation with schizophrenia. Psychosocial theories link it to projection of negative internal feelings and parental modeling. Schizoid personality is also thought to be associated with genes. Schizotypal personality disorder is genetically related to schizophrenia. There is evidence of dysregulation of doperminagenic pathways in these patients. Antisocial personality disorder is thought to be caused by genes which contribute to anti social behavior (Pervin, 1990). Low levels of behavioral inhibition may be reconciled by serotonergic dysregulation in the septohippocampal system. There are also some possibilities of developmental or acquired abnormalities in the prefrontal brain systems and lowered autonomic activity in patients suffering from antisocial personality abnormalities. This may be the logic behind low arousal, poor fear conditioning, and decision making deficits which are reported in antisocial patients (American Psychiatric Association, 2000).   

Borderline personality disorder is thought to be caused by early abuse such as sexual, physical, and emotional abuse. It is mostly formulated as a variant of post traumatic stress disorder. Mood disorders in first degree relatives are also strongly associated with borderline personality disorder. Biological factors such as abnormal monoaminergic functioning and prefrontal neuropsychological dysfunctions are also associated with borderline personality disorder, but this links are not well supported by the research (Marshall,  Serin, 1997).

Very little studies have been conducted to determine the biologic causes of histrionic personality disorder. According to psychoanalytic theories, seductive and authoritarian attitudes demonstrated by the parents especially fathers of these children can lead to this disorder. Narcissistic personality lacks biologic data on biological features (Millon,  Roger, 1995).

According to classic model, narcissistic disorders functions as a defense against realizations of low self esteem. Modern psychodynamic models suggest that this disorder come as a result of imbalance between positive reflection of the developing child and the presence of idealizable adult figure. Avoidant personality disorder is associated with expression of extreme characters of introversion and neuroticism (Costa,  McCrae, 1990). There is no information on biological causes for this disorder but there is a diagnostic overlap with social phobia.