Every mental illness is listed in the Diagnostic and Statistical Manual of Mental Disorders and coded within a five-Axis system. Axis I disorders consist of all clinical disorders and mental illnesses with the exception of mental retardation and personality disorders.
The Five-Axis System
The book that clinicians use to diagnose patients is called the Diagnostic and Statistical Manual of Mental Disorders or the DSM. The DSM is published by the American Psychiatric Association and has been revised numerous times. As of Spring 2013, the DSM-V is the most current edition.
Axis I is a component of the DSM’s five-part axial system, which encompasses all of the dimensions that need to be considered when diagnosing someone with a mental illness. It applies a biopsychosocial approach, in which ‘bio’ refers to the biological factors, ‘psycho’ refers to the psychological aspects and ‘social’ refers to the social features involved. For example, a person with an Axis I diagnosis of major depressive disorder will likely have issues apparent in his or her work, as well as physical problems like headaches or high blood pressure, in conjunction with the symptoms of depression, like sadness and despair.
All clinical disorders are coded on Axis I. They include an enormous variety of disorders, including the following categories:
- Disorders usually first diagnosed in infancy, childhood or adolescence.
This can include learning disorders (like reading or mathematics disorder), conduct disorder, separation anxiety disorder and attention deficit hyperactivity disorder (ADHD). Although most of these disorders are diagnosed during childhood or adolescence, sometimes they are not diagnosed until adulthood.
- Delirium, dementia, amnestic and other cognitive disorders, including dementia of the Alzheimer’s type and vascular dementia. The primary feature of these disorders includes significant disturbances in cognition that result in severe changes in functioning.
- Mental disorders due to a general medical condition, which are characterized by the presence of mental symptoms that are directly linked to the physiological consequences of a medical condition. The symptoms cannot be better accounted for by another mental illness. The symptoms also cannot occur exclusively during the course of a delirium.
- Substance-related disorders include the taking of a drug or substance as well as the side effects that may occur as a result of substance consumption. There are a variety of substance-related disorders categorized by the type of drug, including caffeine, alcohol, nicotine, opioids and inhalants.
- Schizophrenia and other psychotic disorders include psychotic symptoms as the leading symptom. Psychotic disorders are mental illnesses that include the presence of delusions or hallucinations. Delusions are beliefs that are false but that the person holds to be true. They tend to be irrational and unsupported.
For example, many schizophrenic people have delusions that the government is spying on them, so they display paranoid behaviors. Hallucinations can be auditory or visual experiences that the person encounters despite no presence of an actual stimulus. It is very common for schizophrenic people to hear voices and/or see things that are not really there.
- Mood disorders are mental illnesses in which a disturbance in a person’s mood is the primary symptom.
Mood disorders include major depressive disorder, dysthymic disorder, bipolar I disorder, bipolar II disorder, and cyclothymic disorder.
- Anxiety disorders, like panic attack, agoraphobia, social phobia, obsessive-compulsive disorder and posttraumatic stress disorder. Anxiety disorders most often include excessive anxiety, apprehension and worry as primary symptoms.
- Somatoform disorders are mental illnesses that include the presence of physical symptoms that are not explained or linked to any medical illness.
The symptoms will cause significant distress and impairment in functioning that can be seen in multiple areas of functions, including social, occupational and interpersonal. Somatoform disorders include somatization disorder, conversion disorder, body dysmorphic disorder and pain disorder.
- Factitious disorders are distinguished by psychological or physical symptoms that are intentionally designed to put the individual in the role of a ‘sick’ person. While there is in fact no physical illness, the individual experiences an actual, psychological need to play the role of the sick person.
- Dissociative disorders are present when there is a disruption in the processes of consciousness, memory or perception. These include dissociative amnesia, dissociative fugue and depersonalization disorder.
- Sexual and gender identity disorders is the category that includes paraphilias and gender identity disorder, which is an intense identification with the opposite sex. Sexual dysfunctions are also listed under this category on Axis I.
- Eating disorders are severe disturbances in people’s eating behaviors.
Anorexia nervosa and bulimia nervosa are the two most commonly diagnosed eating disorders.
An eating disorder is a severe disturbance in eating behavior
- Sleep disorders include disorders that severely impact a person’s normal sleep and include dyssomnias, narcolepsy and sleep terror disorder.
- Impulse control disorders not otherwise classified include disorders of impulse control that are not classified anywhere else in the DSM, but that are coded on Axis I. These include kleptomania, pyromania and trichotillomania.
- Adjustment disorders involve a psychological response to a stressor that results in severe and clinically significant behavioral and emotional symptoms.
These disorders can be present with depressed mood, with anxiety or with a mix of both anxiety and depression.
- There is also an other conditions category that consists of problems that are not related to a mental disorder or symptoms that require separate attention from the mental disorder that causes them.
Diagnosing Axis I Disorders
It is possible for one individual to have more than one Axis I disorder or to have an Axis I disorder along with an Axis II disorder. When a person suffers from two or more disorders at the same time, they have co-occurring disorders. For example, someone with a substance-related disorder along with another Axis I or Axis II disorder suffers from co-occurring disorders. If no Axis I disorder is present, then the proper DSM code is V71.
09. If the Axis I diagnosis is deferred, meaning that we need to obtain more information before we can reach a diagnosis, the DSM code on Axis I is 799.9.
Let’s review. Axis I is a category of disorders defined by the Diagnostic and Statistical Manual of Mental Disorders. These include a wide array of clinical disorders and mental illnesses, including, but not limited to, mood disorders, anxiety disorders, and eating disorders.
Given the complexities of symptoms, only a trained professional can accurately diagnose an individual with an Axis I disorder.