CRITÉRIOS DIAGNÓSTICOS DO TRANSTORNO DE ANSIEDADE GENERALIZADO

CLINICAL MANIFESTATIONS AND DIAGNOSIS:
Diagnostic
criteria from the DSM-IV for GAD include excessive anxiety and worry
about a number of events or activities, occurring more days than not for
at least six months, that are out of proportion to the likelihood or
impact of feared events.
Affected patients also present with somatic symptoms, including
fatigue, muscle tension, memory loss, and insomnia, and, as noted above,
other psychiatric disorders.
They often have little insight into the connection between reported
worries, current life stress, and their physical symptoms.
Figure 1 presents a diagnostic algorithm to help distinguish GAD from major depression and other anxiety disorders(figure1).

A seven-item anxiety questionnaire (GAD-7) has been developed and validated in a primary care setting (table 2).
This patient self-assessment tool may facilitate screening, but
positive screens should be followed by clinician interview to establish
the diagnosis of GAD. A score of 10 or greater on the GAD-7 represents a
reasonable cut point for identifying cases of GAD with a sensitivity of
89 percent and specificity of 82 percent. Cut points of 5, 10, and 15
have been established as representing mild, moderate, and severe levels
of anxiety on the GAD-7.
The GAD-7 tool has been validated to screen for generalized anxiety, as
well as for other types of anxiety (panic disorder, social anxiety
disorder, and posttraumatic stress disorder).
Additionally, the first two items of the GAD-7 tool (referred to as the
GAD-2), with a cutoff score of 3 or more leading to further evaluation,
may be equally sensitive to the GAD-7.

Many
patients have the full constellation of symptoms that meet the DSM-IV
criteria, but have had symptoms for a shorter period than the required
six months. These individuals often have symptoms of anxiety as a result
of a specific stressor, or symptoms that occur within three months of
the onset of a stressor; they fulfill the DSM-IV diagnostic criteria for
"adjustment disorder with anxious mood" rather than GAD. Patients with
adjustment disorder may have considerable impairment in social
relationships and occupational functioning.
Patients should be
screened for comorbid psychiatric disorders and an organic etiology for
anxiety by careful history taking, a complete physical examination, and
appropriate laboratory studies:

• The initial interview should be open-ended and unhurried; family members should be involved when appropriate.
  
• The
  medical history should focus upon possible contributory factors
  relating to current medical disorders, medication side effects, or
  substance abuse.
  
• The
  psychosocial history should screen for comorbid psychiatric disorders
  such as major depression and agoraphobia, stressful life events, family
  psychiatric history, current social history, substance abuse history
  (including caffeine, nicotine, and alcohol), and past sexual, physical
  and emotional abuse, or emotional neglect.
  
• Laboratory studies to consider include a complete blood count, chemistry panel, serum thyrotropin (TSH),
  urinalysis, electrocardiogram (in patients over 40 with chest pain or
  palpitations), and any other specific studies required to diagnose a
  suspected medical cause of anxiety. Urine or serum toxicology
  measurements or drug levels can be obtained for drugs or medications
  suspected in the etiology of anxiety.
  

REFERÊNCIA: UpToDate - Generalized anxiety disorder: Epidemiology, clinical manifestations, and diagnosis