Comorbidity Patterns in Generalized Anxiety Disorder

Abstract

This article aims to review the comorbidity patterns in generalized anxiety disorder. This disorder is characterized by excessive anxiety and worry that is present in great part of the days, lasting at least six months. The focus of worry is concentrated on future events, past transgressions, financial matters, and health. Generalized anxiety disorder is comorbid with several disorders. Among anxiety disorders, social phobia and panic disorder and agoraphobia have the more prevalence. Generalized anxiety disorder is also comorbid with other mental disorders that belongs to another groups, for instance major depressive disorder and dysthymia, dependent, avoidant, obsessive-compulsive personality disorder, and alcohol and substance use disorders. Physical conditions has been associated to generalized anxiety disorder, namely gastrointestinal problems, that includes ulcers and stomach distress and also irritable bowel syndrome.

Keywords: Generalized Anxiety Disorder; Comorbidity; Diagnosis

Introduction

The main features of generalized anxiety disorder consists of excessive anxiety and worry that occurs the majority of the days and last at least six months. People who receives a diagnosis of generalized anxiety disorder demonstrates worry that are focused on external dangers, for instance events that can happen in the future, past transgressions, financial matters, and their own health and that of loved ones) [1]. For a diagnosis of generalized anxiety disorder, although the likelihood that these events will actually occur is very low, people perceive their outcomes as catastrophic [2]. In children, the worry is about their abilities or the quality of their academic performance. Worry is out of proportion to the actual situation, and is described as uncontrollable and accompanied by physical symptomathology that include muscle tension, restlessness or feeling keyed up or on edge, being easily fatigued, difficulty concentrating, sleep disturbance, and irritability. Cognitive symptomathology which are associated to generalized anxiety disorder include an inability to tolerate uncertainty [3], so people who are diagnosed with generalized anxiety disorder do attempts in order to control their worries by using of distraction from the thoughts, avoidance places that bring on the worrisome thoughts, seeking reassurance from other people, and by engaging in behaviors that make them feel safed, such as having a plan in the case their worry thoughts is actually true [4]. In general these people may say that always find something to worry about, and often have at least one other psychological disorder [5,6], that usually consists of another anxiety disorder or depression. However, worries demonstrated by people with a diagnosis of generalized anxiety disorder have higher severity; they complain with more frequency of muscle tension, feeling restless, and feeling keyed up or on edge [5].

The diagnosis of generalized anxiety disorder is more usual in adults than in children [2], and in general starts in the late tens through the late twenties [7]. Generalized anxiety disorder has a gradual beginning and usually is defined as a chronic condition [8]. In addition to the course of generalized anxiety disorder being chronic, it is also considered to be fluctuating [9]. Furthermore, the functional imparment linked to the diagnosis of generalized anxiety disorder is significant, with 56.3% of people described as severely disabled [10], and has an important impact on physical health due to the increase of the risk of cardiac problems such as cardiovascular death and nonfatal myocardial infarction, for instance heart attacks; [9] and inflammatory bowel disease [11]. A high number of individuals with generalized anxiety disorder seek for treatment from primary care physicians. In fact, more than 12% of people who seek treatment from their primary care physicians do it due to the symptoms of generalized anxiety disorder [12].

The lifetime prevalence of generalized anxiety disorder is situated at 5.7% of the adult general population [13]. In adolescents, is estimated a prevalence of 3%, and increases to 5% if the need for symptom duration is dropped from six months to three months [14].

Among children, the prevalence of generalized anxiety disorder may be estimated in 15% [15]. Feelings of tension and apprehension in these population are considered common and are a negative selfimage and the need for reassurance [16]. People with thirteen and fourteen years old have feelings of restlessness and fewer overall symptoms are less often reported than they are among seventeen to eighteen years old [14].

The onset of generalized anxiety disorder is usually associated to negative, or very important life events [17]. The diagnosis of generalized anxiety disorder is more common among racial/ethnic minorities and people of low socioeconomic status [7].

Comorbidity

A great number of individuals that receives a diagnosis of generalized anxiety disorder also meet diagnostic criteria for other mental disorder [18]. The anxiety disorder that is more considered in people with generalized anxiety disorder is social phobia, as 68% of people with generalized anxiety disorder also suffer from social phobia, panic disorder and agoraphobia [19]. In regards to affective disorders, 42% of people diagnosed with generalized anxiety disorder had a history of major depressive episodes [20]. Over than 65% of individuals who seek for treatment due to the diagnosis of dysthymia also were diagnosed with generalized anxiety disorder [21]. The diagnosis of generalized anxiety disorder can have features of a personality disorder, particularly those that are included in Cluster C. According to Sanderson and colleagues [22], almost half of individuals diagnosed with generalized anxiety disorder were also diagnosed with a Axis II disorder. Among Axis II disorders, the most frequent diagnosis were avoidant and dependent personality disorders [23]. The authors found a specific association between the diagnosis of generalized anxiety disorder and obsessive-compulsive personality disorder that was second only to the association found between social phobia and avoidant personality disorder [22]. Generalized anxiety disorder has also an association with elevated rates of alcohol and substance use disorders. An epidemiological study found that the prevalence of substance use disorders among people with a diagnosis of generalized anxiety disorder was 19.02%, and the prevalence of an alcohol use disorder was 14.82% [24].

People diagnosed with generalized anxiety disorder visit with high frequency primary care physicians. Roy-Byrne and Wagner [25], in their reviews about prevalence rates of generalized anxiety disorder within the primary care setting found that 2.8% to 8.5% of medical patients who visits their physicians for any reason also meet diagnosis criteria for generalized anxiety disorder, approximately twice the rate reported in community epidemiological surveys. Many individuals diagnosed with generalized anxiety disorder first seek treatment due to their anxiety-related symptoms in medican settings, wanting relief from insomnia, restlessness, or chronic muscle tension. Generalized anxiety disorder may have a co-occurrence with medical conditions, particularly those that are involved with the gastrointestinal system. The gastrointestinal problems that includes ulcers and stomach distress appear to accompany generalized anxiety disorder in more percentage in comparison with other conditions [26]. Additional research have examined the association that exists between generalized anxiety disorder and the irritable bowel syndrome and was found that 37% of a clinical generalized anxiety disorder sample also met the diagnostic criteria for irritable bowel syndrome [27], and 34% of a sample constituted by patients with irritable bowel syndrome had a lifetime history of generalized anxiety disorder [28].

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