What are psychiatric disorders? |

Causes and Symptoms

Many centuries ago, physicians began to understand that psychiatric disorders such as depression arose from abnormalities in brain structure or chemistry. As the field of psychiatry developed, medicine has had a profound influence in establishing the biomedical model to define and treat mental disorders. Sigmund Freud and other influential psychiatrists working in the late nineteenth century broadened the understanding of how emotional pain and trauma experienced during a person’s childhood can contribute profoundly to the occurrence and course of mental disorders. The medical influence on the field of psychiatry was deepened and broadened by the contribution of neuroscience. Scientists who began studying the brain more intensively, beginning in the early twentieth century, proved the relationship of brain function to speech, learning, comprehension, memory, emotional regulation, and other important human abilities. Technologies developed in the late twentieth century, such as functional magnetic resonance imaging (fMRI) and genetic testing, have furthered psychiatrists' understanding of the biological, genetic, and neurological basis of a number of mental disorders.

Despite long and exacting efforts to understand mental illness, much remains to be explored. While psychiatrists would prefer to base their diagnoses on knowing the causes and the biological or neurological mechanisms of mental disorders, this knowledge has proved to be elusive. Therefore, most psychiatric diagnoses are based on the psychiatrist recognizing a pattern of symptoms and a typical course of disease. During World War II, psychiatrists realized that their colleagues differed widely in how they recognized and described various mental illnesses. Bureaucratic and professional forces coalesced in a drive to make the diagnosis of psychiatric disorders more systematic. In 1952, the American Psychiatric Association issued a manual that sought to clarify the diagnostic process. Unfortunately, the early manuals proved to be impractical and were largely ignored by psychiatrists. This changed when a more rigorous effort culminated in the publication of the third edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-III) in 1980. This text became widely accepted as the standard reference for psychiatrists to use when diagnosing psychiatric disorders. The manual has been strengthened and revised several times; a fifth edition, known as DSM-5, was published in 2013. Scientists and clinicians continue their work on the manual to correct flaws, incorporate research findings, and explore new areas. However, shortly before the publication of the DSM-5 in May 2013, the US National Institute of Mental Health issued a statement condemning the DMS-5's "lack of validity," noting that "DSM diagnoses are based on a consensus about clusters of clinical symptoms, not any objective laboratory measure." While psychiatrists agree that standard definitions of psychiatric disorders are needed to clarify their thinking, permit easier communication, improve treatment planning, and stimulate further research, a growing number of psychologists recognize the need for more accurate diagnostic criteria that are based on genetic, neurophysiological, and biological measures. While psychiatrists agree that a more accurate diagnostic system based on biomarkers is needed, the technology and research to establish such diagnostic criteria are not yet available. Therefore, the symptom-based diagnostic criteria put forth in the DSM-5 remain the most widely used in the field of psychiatry.

When using the DSM-5, psychiatrists must find that the person exhibits specific signs and symptoms and has maintained this clinical picture for a sufficient length of time to warrant being diagnosed with a psychiatric disorder. The DSM-5 assigns a specific code for each psychiatric diagnosis, which facilitates administrative and statistical work. The diagnostic codes in the DSM-5 are compatible with the coding system used in the ninth edition of the International Classification of Diseases (ICD-9-CM), published by the World Health Organization. This coding system uses five-digit numerical codes. Contributing environmental factors are represented in the DSM-5 through an expanded set of ICD-9-CM codes, which provide clinicians with a way to indicate other issues that are affecting the presentation or course of treatment of the primary mental disorder. The tenth edition of the International Classification of Diseases (ICD-10-CM) is scheduled to be released in 2014. The ICD-10-CM coding system uses a combination of letters and numbers in its codes, and the DSM-5 contains both the ICD-9-CM and the ICD-10-CM coding systems to facilitate the transition to the ICD-10-CM coding system.

Furthermore, the DSM-5 combined the first three axes of the multiaxial diagnostic system used in the fourth edition of the DSM (DSM-IV-TR) into one list that includes all disorders. The DSM-IV-TR had listed clinical disorders on five separate axes, with Axis I referring to the principal disorder, Axis II indicating any additional personality disorder that might affect the Axis I disorder, Axis III indicating any medical problems that might affect the presentation or treatment of the principal disorder; Axis IV noting any psychosocial or contextual factors, and Axis V noting any disability. The DSM-5 introduced a nonaxial diagnostic system, combining Axes I, II, and III into one list, with an expanded set of ICD-9-CM codes to note any psychosocial or environmental factors and disability (formerly Axes IV and V).

Several major diagnostic categories of psychiatric disorders are shown in the DSM-5. These include neurodevelopmental disorders; schizophrenia spectrum and other psychotic disorders; bipolar and related disorders; depressive disorders; anxiety disorders; obsessive-compulsive and related disorders; trauma- and stressor-related disorders; dissociative disorders; somatic symptom and related disorders; feeding and eating disorders; sleep-wake disorders; sexual dysfunctions; gender dysphoria; disruptive, impulse-control, and conduct disorders; substance-related and addictive disorders; neurocognitive disorders; and paraphilic disorders. This listing demonstrates the breadth of problems that are seen and treated by psychiatrists and other mental health practitioners.

Research shows that, on average, 26.2 percent of adults in the United States will experience one or more psychiatric disorders in a given year. Globally, approximately 10 percent of the adult population will have a psychiatric disorder, although psychologists believe the actual rates of mental illness are underreported in many developing countries. The most common disorders are anxiety disorders and mood disorders, such as depression.

Researchers learned that people who experience their first symptoms later in life generally have a better chance of recovering, but almost all people who suffer from a psychiatric disorder will experience distressing symptoms for several years. More men than women, the data show, have suffered a psychiatric disorder at some point in life, although women are more likely than men to experience anxiety or mood disorders. According to researchers, the differences in prevalence among the races may be more reflective of survey methods than of ethnic origins. Higher rates of mental illness are found among people who are poor and who fail to complete high school. People who suffer from one psychiatric disorder were found by researchers to be at a high risk (60 percent) for having another mental health disorder at some time during their lives.

Treatment and Therapy

Making an accurate diagnosis of psychiatric disorders is essential to treating problems properly, since many can be improved through the application of psychosocial, somatic, drug, and adjunctive therapies. For example, it is said that most people who suffer from major depression can be treated successfully with brief psychotherapy, a course of medication, or a combination of both. The somatic technique of exposing a person each day to a bank of bright lights (light therapy) has been used successfully to treat
seasonal affective disorder (depression associated with a specific season, especially winter). Many depressed people and their families have been helped by the adjunctive therapy of participating in a support group.

The use of laboratory tests to clarify psychiatric diagnosis is growing in importance. Only a few disorders can be revealed by laboratory tests, but research is being conducted to validate such testing and to increase its scope and usefulness. Some tests are done routinely to rule out medical problems that may be causing the psychiatric problems the person is experiencing or to ensure that the patient can take needed medication.

Drugs have been used in the United States to treat psychiatric disorders since the early 1950s, and new medications are introduced frequently. The distressing thought disturbances experienced by people suffering from schizophrenia have been treated with antipsychotic drugs. Antipsychotics also are used to treat psychotic symptoms such as the hallucinations and delusions experienced by some people who are suffering from depression or other mood disorders. Several classes of antipsychotics have been developed.
Lithium carbonate is the drug most commonly used to treat people suffering from bipolar disorders, in which patients experience swings in mood from the highs of mania to the lows of depression. Various classes of
antidepressants such as tricyclics and
monoamine oxidase inhibitors (MAOIs) are used to treat people suffering from depression. Many people experiencing symptoms associated with anxiety disorders have been helped through the use of benzodiazepines and other anxiolytics. Central nervous system
stimulants (psychostimulants) are used to treat narcolepsy, a disorder in which people have trouble staying awake. Psychostimulants also are used to treat
Attention-deficit disorder (ADD), because the stimulants have the paradoxical effect of reducing the behaviors that disrupt classroom work and life at home. The drugs decrease excessive physical activity and have been shown to improve an individual's attention to adult guidance, increase attention span and memory, and lessen the individual's tendency to be distracted from tasks and to act impulsively. The person with ADD also is helped with behavior management techniques and careful control of the environment to reduce sources of external stimulation.

Unfortunately, the use of drugs in treating psychiatric disorders is not problem-free. Almost all psychopharmaceuticals have side effects that can be serious enough to prevent their use in treatment. A growing number of psychiatrists have expressed their concern over what they believe to be widespread overdiagnosis and overtreatment for psychiatric disorders in the United States; many patients respond well to simple lifestyle changes, such as increased physical activity or brief therapeutic interventions, so psychiatrists should prescribe psychopharmaceutical medications judiciously. Some people must take other prescription drugs that preclude the use of the drug needed to treat the psychiatric disorder. The possibility of overdose by people who have thoughts of taking their lives can limit the use of possibly toxic drugs. Some people are not helped by drug therapy, are reluctant to take drugs, or fail to take drugs properly. For such people, it is fortunate that other forms of treatment can be used.

Many people who suffer from psychiatric illness have been helped by trained psychotherapists, such as psychiatrists, psychologists, social workers, counselors, and members of the clergy. Many forms of
psychotherapy are practiced. The aims of psychotherapy can be to help the person deal well with life’s stresses and crises, confront and resolve psychological conflict, avoid interpersonal problems, and find more satisfaction and fulfillment in life. Psychotherapy is delivered to individuals, couples, families, and other groups. More emphasis is being placed on conducting psychotherapy only for a limited time, because this approach is preferred by most patients and their insurance companies and because research results support its effectiveness.

Behavioral therapy can be used to help the person to change specific behaviors that cause problems. Behavioral therapy has been used to treat several psychiatric disorders, including alcohol and drug dependence, anxiety, phobias, autism spectrum disorders, and eating disorders. Systematic desensitization has been used to help people who have irrational fears, or phobias. The patient is gradually introduced to the situation that elicits the fearful response and is taught to use relaxation techniques to reduce anxiety and to bring fears under personal control. In behavior modification programs, unwanted behavior is defined, targeted, reduced, and eliminated. At the same time, the person is rewarded for behaving properly.

Electroconvulsive therapy (ECT), formerly called shock therapy, is used generally to treat people with severe depression who have not responded to less intrusive treatment methods. In ECT, the patient is exposed to an electric current that is passed through electrodes taped to the scalp. The current causes the person to experience a brief seizure, usually for less than a minute. This treatment method has been used for many years, and several improvements have been made to make the procedure safer and less damaging to the person’s memory.

Treatment of psychiatric disorders is usually delivered in the community where the affected person lives. In the United States, legislation in the 1960s caused federal funds to be used to build and staff community mental health centers. Many health insurance providers will pay part of the fees charged by private therapists, which allows some people to afford their services. Alcohol and drug treatment programs generally offer people either short-term residential or outpatient services. Many people are served in institutional settings, such as mental hospitals and nursing homes. Some use services provided by governmental funding.

Many people who have suffered psychiatric disorders recover completely; investigators find a 38 percent remission rate. The researchers were surprised to learn that people are most likely to recover from alcohol and drug abuse, generalized anxiety, and antisocial personality. Complete freedom from distressing symptoms and episodes is less likely for those who suffer from mania, obsessive-compulsive disorder (in which the person performs repetitive rituals to allay anxiety caused by disturbing thoughts or fears), and schizophrenia (a disorder typified by thought disturbances such as hallucinations and delusions, mood changes, communication problems, and unusual behaviors). However, with a combination of pharmacological and psychosocial treatments and interventions, 70 to 90 percent of patients with psychiatric disorders experience a reduction of symptoms and improved quality of life, even without achieving full remission.

A large number of people who suffer mental illness have never been treated. Researchers estimate the economic cost of untreated psychiatric disorders in the United States to be more than $100 billion each year.

Perspective and Prospects

Early medical documents show that mental illness has always been an area of significant concern. Symptoms of mental illness were described in the Bible, and they were studied and treated in classical times. Interest in understanding mental disorders waned during the medieval period, when it was thought that sufferers were possessed by demons or were being punished by God. Mentally ill people were often maltreated and incarcerated. Finally, the foundation was laid in the late sixteenth century for a more complete understanding of psychiatric disorders: In 1586, Timothy Bright, a physician, published the first English-language text on mental illness, entitled Treatise of Melancholie.

In late eighteenth-century France, Philippe Pinel took over the management of a hospital for insane men and not only advocated more humane treatment of mentally ill people but also took steps to free them from the chains and other punishing devices that they were forced to endure. Pinel instituted the scientific study of mental illness. He tracked the prevalence of mental disorders, conducted studies to learn the natural course of mental illness, and established a treatment model followed by the more progressive psychiatric facilities.

The brain was studied even more intensely in the nineteenth century. During this era, scientists made important contributions to the understanding of how certain parts of the brain are responsible for specialized functions. They learned that particular brain regions are related to speech and language, movement, sensations, learning, understanding, and emotions. Emil Kraepelin correlated information about the age of onset, natural course, and length of time of particular mental disorders. He used the information that he organized to develop the first classification system of psychiatric disorders. Among the maladies he named were dementia praecox (now called schizophrenia), dementia in the elderly (now called Alzheimer’s disease), and manic-depressive illness (bipolar disorder).

While neuroscientists were making significant contributions to the understanding of the brain, psychiatrist Sigmund Freud was advancing his study of hysteria and its connection with childhood trauma. He used hypnosis and free association to release and resolve underlying misconceptions and fears and to give the patient relief from debilitating trauma and its associated symptoms. He also produced theories on psychological function and structure and on psychotherapy.

During the twentieth century, psychiatrists drew on a broad array of disciplines to improve the diagnosis and treatment of psychiatric disorders, including the study of brain chemistry, biology, structure, and functioning. Advances in neuroimaging techniques allowed scientists to study and sometimes diagnose brain dysfunction. Specialized drugs were developed to be used in the treatment of specific mental disorders. Since 1952, the American Psychiatric Association has published a series of diagnostic and statistical manuals designed to bring order to the study, diagnosis, and treatment of psychiatric disorders. Psychiatrists continue to work toward developing more accurate diagnostic criteria and more effective treatments for psychiatric disorders.

Bibliography

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5th ed. Arlington, Va.: American Psychiatric Association, 2013.

Black, Donald W., and Nancy C. Andreasen. Introductory Textbook of Psychiatry. 5th ed. Washington, D.C.: American Psychiatric Press, 2010.

North, Carol S., and Sean H. Yutzy. Goodwin and Guze's Psychiatric Diagnosis. 6th ed. New York: Oxford University Press, 2010.

Insel, Thomas. "Transforming Diagnosis." National Institute of Mental Health, April 29, 2013.

Kring, Ann M., et al. Abnormal Psychology. 11th ed. Hoboken, N.J.: John Wiley & Sons, 2010.

Oltmanns, Thomas F., et al. Case Studies in Abnormal Psychology. 9th ed. Hoboken, N.J.: John Wiley & Sons, 2012.

Sadock, Benjamin J., Virginia A. Sadock, and Pedro Ruiz, eds. Kaplan and Sadock’s Comprehensive Textbook of Psychiatry. 9th ed. Philadelphia: Lippincott Williams & Wilkins, 2009.