What symptoms and criteria support a diagnosis of generalized anxiety disorder in an adult with persistent worry after ruling out medical, substance, and safety causes?

Diagnostic Criteria for Generalized Anxiety Disorder

Generalized anxiety disorder is diagnosed when a patient exhibits excessive, uncontrollable worry persisting for at least 6 months across multiple life domains, accompanied by at least three of six associated symptoms (restlessness, fatigue, concentration difficulty, irritability, muscle tension, or sleep disturbance), causing significant functional impairment. 1, 2

Core Diagnostic Features

Primary Symptom: Excessive Worry

• The worry must be excessive and disproportionate to actual circumstances or risks 1
• Patients describe the worry as "uncontrollable" or difficult to control 1, 3
• The worry must span multiple life domains (health, family, work, finances) rather than focusing on a single concern 4, 1
• Duration requirement: symptoms must persist for at least 6 months 2, 1

Six Associated Physical and Psychological Symptoms

The American Psychiatric Association requires at least three of the following symptoms to be present more days than not 1, 5:

• Restlessness or feeling keyed up or on edge 6, 5
• Being easily fatigued 6, 5
• Difficulty concentrating or mind going blank 6, 5
• Irritability 6, 5
• Muscle tension 6, 5
• Sleep disturbance (difficulty falling or staying asleep, or restless, unsatisfying sleep) 6, 5

Functional Impairment

• Symptoms must cause clinically significant distress or impairment in social, occupational, or other important areas of functioning 3, 7
• The American College of Oncology recommends assessing specific examples: missing work, avoiding social situations, difficulty completing household tasks 7
• Moderate GAD typically causes mild to moderate functional impairment, while severe GAD markedly interferes with daily functioning 3, 7

Validated Screening Tools and Scoring

GAD-7 Scale (Primary Screening Instrument)

The American College of Physicians recommends the GAD-7 as the primary screening tool, assessing seven key symptoms over the past 2 weeks 4, 3:

GAD-7 Severity Stratification: 3, 4, 6

• 0-4: None/minimal symptoms - monitor only
• 5-9: Mild anxiety - low-intensity interventions
• 10-14: Moderate anxiety - referral to psychology/psychiatry recommended
• 15-21: Severe anxiety - immediate mental health specialist referral required

GAD-7 Content Items

Each item is rated 0-3 (not at all, several days, more than half the days, nearly every day) 3:

• Feeling nervous, anxious, or on edge 3
• Cannot stop or control worry 3
• Worrying too much about different things 3
• Trouble relaxing 3
• Being so restless that it's hard to sit still 3
• Becoming easily annoyed or irritable 3
• Feeling afraid as if something awful might happen 3

Alternative Screening Tools

• GAD-2 (ultra-brief): Uses first two GAD-7 items; score ≥3 indicates need for full assessment 4
• GAD-Q-IV: 9-item self-report assessing DSM-IV criteria including uncontrollable worry, functional impairment, physical symptoms, and subjective distress 3
• Penn State Worry Questionnaire (PSWQ): 16-item scale assessing worry severity and controllability 3

Essential Exclusion Criteria

Medical Causes to Rule Out

The Journal of Clinical Oncology mandates ruling out medical conditions before diagnosing GAD 3, 2:

• Hyperthyroidism 2
• Hyperparathyroidism 2
• Cardiac arrhythmias 2
• Other chronic medical illnesses 3

Substance-Induced Anxiety

• Substance use or abuse (alcohol, stimulants, caffeine) must be identified and treated concurrently 3, 8
• Medication-induced causes (e.g., interferon, corticosteroids) should be determined 3

Safety Concerns Requiring Immediate Action

The American College of Oncology recommends immediate screening for 7:

• Suicidal ideation or self-harm thoughts (requires immediate psychiatric referral or emergency evaluation) 7
• Intent to harm others 7
• Severe agitation, psychotic symptoms, or confusion/delirium 7

Risk Factors and Comorbidities to Assess

Psychiatric History and Comorbidities

• Prior diagnosis of any anxiety disorder with or without prior treatment 3
• Major depressive disorder co-occurs in approximately 31% of GAD cases - screen with PHQ-9 1, 3
• Other comorbid psychiatric disorders (mood disorders) 3
• Other anxiety disorders: panic disorder, social phobia, specific phobias, PTSD 3, 4

Substance Use

• History of alcohol or substance use or abuse 3
• Current presence of alcohol or substance use or abuse 3

Other Risk Factors

• Presence of other chronic illnesses 3
• Family history of anxiety or mood disorders 7
• Major life stressors 4

Differential Diagnosis Considerations

Distinguishing GAD from Other Anxiety Disorders

The Diagnostic and Statistical Manual of Mental Disorders distinguishes GAD by its multi-domain worry pattern 4:

• Panic disorder: recurrent unexpected panic attacks rather than persistent worry 2, 9
• Social anxiety disorder: fear focused specifically on social/performance situations 9
• Specific phobias: anxiety limited to specific objects or situations 4
• PTSD: anxiety related to specific traumatic event 4

GAD versus Adjustment Disorder

• Adjustment disorder requires a clear precipitating stressor and typically resolves when stressor is removed 7
• GAD involves worry about multiple areas without necessarily having an identifiable precipitant 4

GAD versus Normal Worry

• GAD must be distinguished from normal worries and fears common to everyday life 4, 1
• The key differentiators are: excessive nature, uncontrollability, multi-domain focus, duration ≥6 months, and functional impairment 1, 2

Cultural Considerations

Somatic Symptom Presentation

• Non-Western populations more likely to report somatic symptoms rather than psychological symptoms 7
• Common somatic presentations include: fatigue, muscle tension, sleep disturbance, palpitations, dizziness, indigestion 7
• Cultural factors may influence presentation and require culturally sensitive assessment approaches 4

Common Diagnostic Pitfalls to Avoid

• Missing comorbid depression: Always screen with PHQ-9 or direct questioning about depressed mood and anhedonia 7, 1
• Overlooking substance use disorders: These require concurrent treatment and complicate anxiety management 7, 8
• Ignoring cultural variations: Particularly somatic symptom presentations in non-Western populations 7
• Failing to assess functional impairment: This guides treatment intensity and is essential for diagnosis 7
• Not ruling out medical causes: Thyroid disorders and cardiac conditions must be excluded 2