Etiology - Anxiety, Anxiety Disorders, and Stress-Related Illness

ETIOLOGY

Biologic Theories

Genetic Theories

Anxiety may have an inherited component because first-degree relatives of clients with increased anxiety have higher rates of developing anxiety. Heritability refers to the propor-tion of a disorder that can be attributed to genetic factors:

·    High heritabilities are greater than 0.6 and indicate that genetic influences dominate.

·    Moderate heritabilities are 0.3 to 0.5 and suggest an even greater influence of genetic and nongenetic factors.

·    Heritabilities less than 0.3 mean that genetics are negligible as a primary cause of the disorder.

Panic disorder and social and specific phobias, includ-ing agoraphobia, have moderate heritability. GAD and OCD tend to be more common in families, indicating a strong genetic component, but still require further in-depth study (McMahon & Kassem, 2005). At this point, current re-search indicates a clear genetic susceptibility to or vulner-ability for anxiety disorders; however, additional factors are necessary for these disorders to actually develop.

Neurochemical Theories

Gamma-aminobutyric acid ( -aminobutyric acid [GABA]) is the amino acid neurotransmitter believed to be dysfunc-tional in anxiety disorders. GABA, an inhibitory neurotrans-mitter, functions as the body’s natural antianxiety agent by reducing cell excitability, thus decreasing the rate of neu-ronal firing. It is available in one third of the nerve synapses, especially those in the limbic system and in the locus ceruleus, the area where the neurotransmitter norepineph-rine, which excites cellular function, is produced. Because GABA reduces anxiety and norepinephrine increases it, researchers believe that a problem with the regulation of these neurotransmitters occurs in anxiety disorders.

Serotonin, the indolamine neurotransmitter usually implicated in psychosis and mood disorders, has many subtypes. 5-Hydroxytryptamine type 1a plays a role in anxiety, and it also affects aggression and mood. Serotonin is believed to play a distinct role in OCD, panic disorder, and GAD. An excess of orepinephrine is suspected in panic disorder, GAD, and posttraumatic stress disorder (Neumeister, Bonne, & Charney, 2005).

DISORDER

Agoraphobia is anxiety about or avoidance of places or situations from which escape might be difficult or in which help might be unavailable.

Panic disorder is characterized by recurrent, unexpected panic attacks that cause con-stant concern. Panic attack is the sudden onset of intense apprehension, fearfulness, or terror associated with feelings of impend-ing doom.

Specific phobia is characterized by significant anxiety provoked by a specific feared object or situation, which often leads to avoidance behavior.

Social phobia is characterized by anxiety pro-voked by certain types of social or perfor-mance situations, which often leads to avoidance behavior.

Obsessive–compulsive disorder involves ob-sessions (thoughts, impulses, or images) that cause marked anxiety and/or compulsions (repetitive behaviors or mental acts) that at-tempt to neutralize anxiety.

Generalized anxiety disorder is character-ized by at least 6 months of persistent and excessive worry and anxiety.

Acute stress disorder is the development of anxiety, dissociation, and other symptoms within 1 month of exposure to an extremely traumatic stressor; it lasts 2 days to 4 weeks.

Posttraumatic stress disorder is character-ized by the reexperiencing of an extremely traumatic event, avoidance of stimuli associ-ated with the event, numbing of responsive-ness, and persistent increased arousal; it begins within 3 months to years after the event and may last a few months or years.

Psychodynamic Theories

Intrapsychic /Psychoanalytic Theories

Freud (1936) saw a person’s innate anxiety as the stimulus for behavior. He described defense mechanisms as the human’s attempt to control awareness of and to reduce anx-iety . Defense mechanisms are cognitive distortions that a person uses unconsciously to maintain a sense of being in control of a situation, to lessen discom-fort, and to deal with stress. Because defense mechanisms arise from the unconscious, the person is unaware of using them. Some people overuse defense mechanisms, which stops them from learning a variety of appropriate methods to resolve anxiety-producing situations. The dependence on one or two defense mechanisms also can inhibit emo-tional growth, lead to poor problem-solving skills, and cre-ate difficulty with relationships.

Interpersonal Theory

Harry Stack Sullivan (1952) viewed anxiety as being gen-erated from problems in interpersonal relationships. Care-givers can communicate anxiety to infants or children through inadequate nurturing, agitation when holding or handling the child, and distorted messages. Such commu-nicated anxiety can result in dysfunction such as failure to achieve age-appropriate developmental tasks. In adults, anxiety arises from the person’s need to conform to the norms and values of his or her cultural group. The higher the level of anxiety, the lower the ability to communicate and to solve problems and the greater the chance for anxi-ety disorders to develop.

Hildegard Peplau (1952) understood that humans exist in interpersonal and physiologic realms; thus, the nurse can better help the client to achieve health by attend-ing to both areas. She identified the four levels of anxiety and developed nursing interventions and interpersonal communication techniques based on Sullivan’s interper-sonal view of anxiety. Nurses today use Peplau’s interper-sonal therapeutic communication techniques to develop and to nurture the nurse–client relationship and to apply the nursing process.

Behavioral Theory

Behavioral theorists view anxiety as being learned through experiences. Conversely, people can change or “unlearn” behaviors through new experiences. Behaviorists believe that people can modify maladaptive behaviors without gain-ing insight into their causes. They contend that disturbing behaviors that develop and interfere with a person’s life can be extinguished or unlearned by repeated experiences guided by a trained therapist.