Generalized anxiety disorder
Generalized anxiety disorder, or GAD, is a disorder characterized by diffuse and chronic worry. Unlike people with phobias or post-traumatic disorders, people with GAD do not have their worries provoked by specific triggers; they may worry about almost anything having to do with ordinary life. It is not unusual for patients diagnosed with GAD to shift the focus of their anxiety from one issue to another as their daily circumstances change. For example, someone with GAD may start worrying about finances when several bills arrive in the mail, and then fret about the state of his or her health when it is noticed that one of the bills is for health insurance. Later in the day he or she may read a newspaper article that moves the focus of the worry to a third concern.
A manual commonly used by mental health professionals is the Diagnostic and Statistical Manual of Mental Disorders , also known as the DSM. This manual may also be identified more specifically by edition, such as the DSM, fourth edition text revised, or DSM-IV-TR. The DSM-IV-TR classifies GAD as an anxiety disorder.
Generalized anxiety disorder is characterized by persistent worry that is excessive and that the patient finds hard to control. Common worries associated with generalized anxiety disorder include work responsibilities, money, health, safety, car repairs, and household chores. The ICD-10, which is the European equivalent of DSMIV-TR, describes the anxiety that typifies GAD as "free-floating," which means that it can attach itself to a wide number of issues or concerns in the patient's environment.
DSM-IV-TR specifies that the worry must occur "more days than not for a period of at least six months"; ICD-10 states only that the patient "must have primary symptoms of anxiety most days for at least several weeks at a time, and usually for several months." The patient usually recognizes that his or her worry is out of proportion in its duration or intensity to the actual likelihood or impact of the feared situation or event. For example, a husband or wife may worry about an accident happening to a spouse who commutes to work by train, even though the worried partner knows objectively that rail travel is much safer than automobile travel on major highways. The anxiety level of a patient with GAD may rise and fall somewhat over a period of weeks or months but tends to become a chronic problem. The disorder typically becomes worse during stressful periods in the patient's life.
DSM-IV-TR specifies interference with work, family life, social activities, or other areas of functioning as a criterion for generalized anxiety disorder; ICD-10 does not mention interference with tasks or other activities as a criterion for the disorder. Both diagnostic manuals mention such physical symptoms as insomnia , sore muscles, headaches, digestive upsets, etc. as common accompaniments of GAD, but only DSM-IV-TR specifies that an adult patient must experience three symptoms out of a list of six (restlessness, being easily fatigued, having difficulty concentrating, being irritable, high levels of muscle tension, and sleep disturbances) in order to be diagnosed with the disorder.
Patients diagnosed with GAD have a high rate of concurrent mental disorders, particularly major depression disorder, other anxiety disorders, or a substance abuse disorder. They also frequently have or develop such stress-related physical illnesses and conditions as tension headaches, irritable bowel syndrome (IBS), temporomandibular joint dysfunction (TMJ), bruxism (grinding of the teeth during sleep), and hypertension. In addition, the discomfort or complications associated with arthritis, diabetes, and other chronic disorders are often intensified by GAD. Patients with GAD are more likely to seek help from a primary care physician than a psychiatrist ; they are also more likely than patients with other disorders to make frequent medical appointments, to undergo extensive or repeated diagnostic testing, to describe their health as poor, and to smoke tobacco or abuse other substances. In addition, patients with anxiety disorders have higher rates of mortality from all causes than people who are less anxious.
In many cases, it is difficult for the patient's doctor to determine whether the anxiety preceded the physical condition or followed it; sometimes people develop generalized anxiety disorder after being diagnosed with a chronic organic health problem. In other instances, the wear and tear on the body caused by persistent and recurrent worrying leads to physical diseases and disorders. There is an overall "vicious circle" quality to the relationship between GAD and other disorders, whether mental or organic.
Children diagnosed with GAD have much the same anxiety symptoms as adults. The mother of a six-year-old boy with the disorder told his pediatrician that her son "acted like a little man" rather than a typical first-grader. He would worry about such matters as arriving on time for school field trips, whether the family had enough money for immediate needs, whether his friends would get hurt climbing on the playground jungle gym, whether there was enough gas in the tank of the family car, and similar concerns. The little boy had these worries in spite of the fact that his family was stable and happy and had no serious financial or other problems.
GAD often has an insidious onset that begins relatively early in life, although it can be precipitated by a sudden crisis at any age above six or seven years. The idea that GAD often begins in the childhood years even though the symptoms may not become clearly noticeable until late adolescence or the early adult years is gaining acceptance. About half of all patients diagnosed with the disorder report that their worrying began in childhood or their teenage years. Many will say that they cannot remember a time in their lives when they were not worried about something. This type of persistent anxiety can be regarded as part of a person's temperament, or inborn disposition; it is sometimes called trait anxiety. It is not unusual, however, for people to develop the disorder in their early adult years or even later in reaction to chronic stress or anxiety-producing situations. For example, there are instances of persons developing GAD after several years of taking care of a relative with dementia , living with domestic violence, or living in close contact with a friend or relative with borderline personality disorder .
The specific worries of a person with GAD may be influenced by their ethnic background or culture. DSMIV-TR's observation that being punctual is a common concern of patients with GAD reflects the value that Western countries place on using time as efficiently as possible. One study of worry in college students from different ethnic backgrounds found that Caucasian and African American students tended to worry a variable amount about a wider range of concerns whereas Asian Americans tended to worry more intensely about a smaller number of issues. Another study found that GAD in a community sample of older Puerto Ricans overlapped with a culture-specific syndrome called ataque de nervios , which resembles panic disorder but has features of other anxiety disorders as well as dissociative symptoms. (People experience dissociative symptoms when their perception of reality is temporarily altered— they may feel as if they were in a trance, or that they were observing activity around them instead of participating.) Further research is needed regarding the relationship between people's ethnic backgrounds and their outward expression of anxiety symptoms.
Causes and symptoms
The causes of generalized anxiety disorder appear to be a mixture of genetic and environmental factors. It has been known for some years that the disorder runs in families. Recent twin studies as well as the ongoing mapping of the human genome point to a genetic factor in the development of GAD. A gene related to panic disorder was identified in late 2001, which increases the likelihood that there is a gene or genes that govern susceptibility to generalized anxiety. The role of the family environment (social modeling ) in an individual's susceptibility to GAD is uncertain. Social modeling, the process of learning behavioral and emotional response patterns from observing one's parents or other adults, appears to be a more important factor for women than for men.
Another factor in the development of GAD is social expectations related to gender roles. A recent Swiss study corroborated earlier findings that women have higher levels of emotional distress and lower quality of life than men. The higher incidence of GAD in women has been linked to the diffuse yet comprehensive expectations of women as caregivers. Many women assume responsibility for the well-being and safety of other family members in addition to holding a job or completing graduate or professional school. The global character of these responsibilities as well as their unrelenting nature has been described as a mirror image of the persistent but nonspecific anxiety associated with GAD.
Socioeconomic status may also contribute to generalized anxiety. One British study found that GAD is more closely associated with an accumulation of minor stressors than with any demographic factors. Persons of lower socioeconomic status, however, have fewer resources for dealing with minor stressors and so appear to be at greater risk for generalized anxiety.
One additional factor may be the patient's level of muscle tension. Several studies have found that patients diagnosed with GAD tend to respond to physiological stress in a rigid, stereotyped manner. Their autonomic reactions (reactions in the part of the nervous system that governs involuntary bodily functions) are similar to those of people without GAD, but their muscular tension shows a significant increase. It is not yet known, however, whether this level of muscle tension is a cause or an effect of GAD.
The symptomatology of GAD has changed somewhat over time with redefinitions of the disorder in successive editions of DSM. The first edition of DSM and DSM-II did not make a sharp distinction between generalized anxiety disorder and panic disorder. After specific treatments were developed for panic disorder, GAD was introduced in DSM-III as an anxiety disorder without panic attacks or symptoms of major depression. This definition proved to be unreliable. As a result, DSM-IV constructed its definition of GAD around the psychological symptoms of the disorder (excessive worrying) rather than the physical (muscle tension) or autonomic symptoms of anxiety. DSM-IV-TR continued that emphasis.
According to the DSM-IV-TR, the symptoms of GAD are:
- excessive anxiety and worry about a number of events or activities, occurring more days than not for at least six months
- worry that cannot be controlled
- worry that is associated with several symptoms such as restlessness, fatigue , irritability, or muscle tension
- worry that causes distress or impairment in relationships, at work, or at school
In addition, to meet the diagnostic criteria for GAD,
the content or focus of the worry cannot change the diagnosis from GAD to another anxiety disorder such as panic disorder, social phobia , or obsessive-compulsive disorder , and the anxiety cannot be caused by a substance (a drug or a medication).
One categorization of GAD symptoms that some psychiatrists use in addition to the DSM framework consists of three symptom clusters:
- symptoms related to high levels of physiological arousal: muscle tension, irritability, fatigue, restlessness, insomnia
- symptoms related to distorted thinking processes: poor concentration, unrealistic assessment of problems, recurrent worrying
- symptoms associated with poor coping strategies: procrastination, avoidance, inadequate problem-solving skills
It is difficult to compare present statistics for generalized anxiety disorder with those of the 1980s and early 1990s because of changes in the diagnostic criteria for GAD in successive editions of DSM. The National Institute of Mental Health (NIMH) states that as of 2000, 2.8% of the general United States population, or about four million people, have GAD during the course of a given year. One study that used DSM-III-R criteria concluded that 5% of the United States population, or one person in every 20, will develop GAD at some point in their lives. Another range of figures given for the lifetime prevalence of GAD in the American population is 4.1%–6.6%. The figure given for children in the United States is also 5%. Women develop generalized anxiety disorder more frequently than men; the sex ratio is variously given as 3:2 or 2:1. Prevalence across races and ethnic groups is more difficult to determine because of cultural influences on expressions of anxiety.
Some psychiatrists think that generalized anxiety disorder is overdiagnosed in both adults and children. One reason for this possibility is that diagnostic screening tests used by primary care physicians for mental disorders produce a large number of false positives for GAD. One study of the PRIME-MD, a screening instrument for mental disorders frequently used in primary care practices, found that 7% of patients met the criteria for GAD. Follow-up in-depth interviews with the patients, however, revealed that only a third of the GAD diagnoses could be confirmed.
Diagnosis of GAD, particularly in primary care settings, is complicated by several factors. One is the high level of comorbidity (co-occurrence) between GAD and other mental or physical disorders. Another is the considerable overlap between anxiety disorders in general and depression. Some practitioners believe that depression and GAD may not be separate disorders after all, because studies have repeatedly confirmed the existence and common occurrence of a "mixed" anxiety/depression syndrome.
Evaluating a patient for generalized anxiety disorder includes the following steps:
- Patient interview. The doctor will ask the patient to describe the anxiety, and will note whether it is acute (lasting hours to weeks) or persistent (lasting from months to years). If the patient describes a recent stressful event, the doctor will evaluate him or her for "double anxiety," which refers to acute anxiety added to underlying persistent anxiety. The doctor may also give the patient a diagnostic questionnaire to evaluate the presence of anxiety disorders. The Hamilton Anxiety Scale is a commonly used instrument to assess anxiety disorders in general. The Generalized Anxiety Disorder Questionnaire for DSM-IV (GAD-Q-IV) is a more recent diagnostic tool, and is specific to GAD.
- Medical evaluation. Nonpsychiatric disorders that are known to cause anxiety (hyperthyroidism, Cushing's disease, mitral valve prolapse, carcinoid syndrome, and pheochromocytoma) must be ruled out, as well as certain medications (steroids, digoxin, thyroxine, theophylline, and selective serotonin reuptake inhibitors) that may also cause anxiety as a side effect. The patient should be asked about his or her use of herbal preparations as well.
- Substance abuse evaluation. Because anxiety is a common symptom of substance abuse and withdrawal syndrome, the doctor will ask about the patient's use of caffeine, nicotine, alcohol, and other common substances (including prescription medications) that may be abused.
- Evaluation for other psychiatric disorders. This step is necessary because of the frequent overlapping between GAD and depression or between GAD and other anxiety disorders.
In some instances the doctor will consult the patient's family for additional information about the onset of the patient's anxiety symptoms, dietary habits, etc.
There are several treatment types that have been found effective in treating GAD. Most patients with the disorder are treated with a combination of medications and psychotherapy .
Pharmacologic therapy is usually prescribed for patients whose anxiety is severe enough to interfere with daily functioning. Several different groups of medications have been used to treat generalized anxiety disorder.
These medications include the following:
- Benzodiazepines. This group of tranquilizers does not decrease worry, but lowers anxiety by decreasing muscle tension and hypervigilance. They are often prescribed for patients with double anxiety because they act very quickly. The benzodiazepines, however, have several disadvantages: they are unsuitable for long-term therapy because they can cause dependence, and GAD is a long-term-disorder; they cannot be given to patients who abuse alcohol; and they cause short-term memory loss and difficulty in concentration. One British study found that benzodiazepines significantly increased a patient's risk of involvement in a traffic accident.
- Buspirone (BuSpar). Buspirone appears to be as effective as benzodiazepines and antidepressants in controlling anxiety symptoms. It is slower to take effect (about two–three weeks), but has fewer side effects. In addition, it treats the worry associated with GAD rather than the muscle tension.
- Tricyclic antidepressants. Imipramine (Tofranil), nortriptyline (Pamelor), and desipramine (Norpramin) have been given to patients with GAD. They have, however, some problematic side effects; imipramine has been associated with disturbances in heart rhythm, and the other tricyclics often cause drowsiness, dry mouth, constipation, and confusion. They increase the patient's risk of falls and other accidents.
- Selective serotonin reuptake inhibitors. Paroxetine (Paxil), one of the SSRIs, was approved by the Food and Drug Administration (FDA) in 2001 as a treatment for GAD. Venlafaxine (Effexor) appears to be particularly beneficial to patients with a mixed anxiety/depression syndrome; it is the first drug to be labeled by the FDA as an antidepressant as well as an anxiolytic. Venlafaxine is also effective in treating patients with GAD whose symptoms are primarily somatic (manifesting as physical symptoms, or bodily complaints).
Some studies have found cognitive therapy to be superior to medications and psychodynamic psychotherapy in treating GAD, but other researchers disagree with these findings. As a rule, GAD patients who have personality disorders , who are living with chronic social stress (are caring for a parent with Alzheimer's disease , for example), or who don't trust psychotherapeutic approaches require treatment with medications. The greatest benefit of cognitive therapy is its effectiveness in helping patients with the disorder to learn more realistic ways to appraise their problems and to use better problem-solving techniques.
Family therapy is recommended insofar as family members can be helpful in offering patients a different perspective on their problems. They can also help the patient practice new approaches to problem-solving.
Alternative and complementary therapies
Several alternative and complementary therapies have been found helpful in treating patients with generalized anxiety disorder. These include hypnotherapy ; music therapy; Ayurvedic medicine; yoga ; religious practice; and guided imagery meditation .
Biofeedback and relaxation techniques are also recommended for GAD patients in order to lower physiologic arousal. In addition, massage therapy, hydrotherapy, shiatsu, and acupuncture have been reported to relieve muscle spasms or soreness associated with GAD.
One herbal remedy that has been used in clinical trials for treating GAD is passionflower ( Passiflora incarnata ). One team of researchers found that passionflower extract was as effective as oxazepam (Serax) in relieving anxiety symptoms in a group of 36 outpatients diagnosed with GAD according to DSM-IV criteria. In addition, the passionflower extract did not impair the subjects' job performance as frequently or as severely as the oxazepam.
Generalized anxiety disorder is generally regarded as a long-term condition that may become a lifelong problem. Patients frequently find their symptoms resurfacing or getting worse during stressful periods in their lives. It is rare for patients with GAD to recover spontaneously.
As of 2002, the genetic factors involved in generalized anxiety disorder have not been fully identified. In addition, the many stressors of modern life that raise people's anxiety levels are difficult to escape or avoid. The best preventive strategy, given the early onset of GAD, is the modeling of realistic assessment of stressful events by parents, and the teaching of effective coping strategies to their children.
American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th edition, text revised. Washington, DC: American Psychiatric Association, 2000.
"Generalized Anxiety Disorder." Section 15, Chapter 187 in The Merck Manual of Diagnosis and Therapy, edited by Mark H. Beers, M.D., and Robert Berkow, M.D. Whitehouse Station, NJ: Merck Research Laboratories, 2001.
Pelletier, Kenneth R., MD. The Best Alternative Medicine. Part II, "CAM Therapies for Specific Conditions: Anxiety." New York: Simon and Schuster, 2002.
Rowe, Dorothy. Beyond Fear. London, UK: Fontana/Collins, 1987.
World Health Organization (WHO). The ICD-10 Classification of Mental and Behavioural Disorders. Geneva: WHO, 1992.
Brown, Timothy A., Laura A. Campbell, Cassandra L. Lehman, and others. "Current and Lifetime Comorbidity of the DSM-IV Anxiety and Mood Disorders in a Large Clinical Sample." Journal of Abnormal Psychology 110 (November 2001): 585-599.
"Clinical Notes from the APA: Treating Generalized Anxiety Disorder." Psychopharmacology Update 12 (June 2001): 22-25.
Gale, Christopher. "Anxiety Disorder." British Medical Journal 321 (November 11, 2000): 1204-1207.
Gamma, A., and J. Angst. "Concurrent Psychiatric Comorbidity and Multimorbidity in a Community Study: Gender Differences and Quality of Life." European Archives of Psychiatry and Clinical Neuroscience 251 (2001): Supplement 2:1143-1146.
Gliatto, Michael F. "Generalized Anxiety Disorder." American Family Physician 62 (October 1, 2000): 1591-1600, 1602.
Hettema, John M., Michael C. Neale, Kenneth S. Kendler. "A Review and Meta-Analysis of the Genetic Epidemiology of Anxiety Disorders." American Journal of Psychiatry 158 (October 2001): 1568-1578.
"Location of Genes Linked to Obesity and Anxiety Found." Pain & Central Nervous System Week. (October 8, 2001).
Magill, Michael K. "Generalized Anxiety Disorder in Family Practice Patients." American Family Physician 62 (October 1, 2000): 1537-1540.
Preboth, Monica. "Paroxetine Approved for Generalized Anxiety." American Family Physician 64 (October 1, 2001): 1280.
Rynn, Moira A., Lynne Siqueland, Karl Rickels. "Placebo-Controlled Trial of Sertraline in the Treatment of Children with Generalized Anxiety Disorder." American Journal of Psychiatry 158 (December 2001): 2008-2014.
Scott, E. L., W. Eng, and R. G. Heimberg. "Ethnic Differences in Worry in a Nonclinical Population." Depression and Anxiety 15 (2002): 79-82.
Shortt, Alison L., Paula M. Barrett, Tara L. Fox. "Evaluating the FRIENDS Program: A Cognitive-Behavioral Group Treatment for Anxious Children and Their Parents." Journal of Clinical Child Psychology 30 (December 2001): 525.
Tolin, D. F., J. Robinson, C. Gruman, and others. "The Prevalence of Anxiety Disorders Among Middle-Aged and Older Puerto Ricans." Gerontologist (October 15, 2001): 33.
Wagner, Karen D. "Children Who Worry Too Much." Psychiatric Times 17 (September 2000): 9.
Young, A. S., and others. "The Quality of Care for Depressive and Anxiety Disorders in the United States." Archives of General Psychiatry 58 (January 2001): 55-61.
Anxiety Disorders Association of America. 11900 Parklawn Drive, Suite 100, Rockville, MD 20852-2624. (301) 231-9350. <www.adaa.org> .
Anxiety Disorders Education Program, National Institute of Mental Health. 6001 Executive Blvd., Room 8184, MSC 9663, Bethesda, MD 20892-9663. (301) 443-4513. <www.nimh.nih.gov> .
Freedom From Fear. 308 Seaview Avenue, Staten Island, NY 10305. (718) 351-1717. <www.freedomfromfear.com> .
National Mental Health Association. 1021 Prince Street, Alexandria, VA 22314-2971. (800) 969-6642. <www.nmha.org> .
National Institute of Mental Health (NIMH). Anxiety Disorders. NIH Publication No. 00-3879 (2000). <www.nimh.nih.gov/anxiety/anxiety.cfm> .
National Institute of Mental Health (NIMH). Facts About Generalized Anxiety Disorder. NIH publication OM-99 4153, revised edition (2000). <www.nimh.nih.gov/anxiety/gadfacts.cfm> .
Rebecca J. Frey, Ph.D.