Thyroid Function and Anxiety Disorders

Introduction to Thyroid Function Tests

Significant comorbidity exists between anxiety disorders and thyroid dysfunction, with a notable correlation between thyroid hormone levels and anxiety severity in non-medicated patients, as stated by the American Psychiatric Association 1

The American College of Emergency Physicians recommends ordering TSH and free T4 as primary laboratory tests for patients presenting with severe anxiety and panic attacks, with a strength of evidence level of "strong recommendation" 1

The following laboratory tests are recommended for patients with anxiety:

Test	Indication
TSH, free T4	Thyroid dysfunction
Plasma-free metanephrine or urinary vanillylmandelic acid	Suspected pheochromocytoma
Serum serotonin or urinary 5-hydroxyindoleacetic acid	Suspected carcinoid syndrome
CBC	Anemia, infection, or other hematologic abnormalities
CMP	Electrolytes, glucose, kidney and liver function tests
Lipid profile	Standard baseline tests

1, 2, 3

Laboratory testing should be guided by the patient's clinical evaluation, rather than routine extensive testing, as recommended by the American College of Emergency Physicians 3
Targeted tests such as glucose testing should be considered when medical causes of anxiety are suspected based on clinical presentation, as hypoglycemia can present with anxiety-like symptoms 4

Anxiety disorders commonly co-occur with depression, ADHD, and substance use disorders, and focus on psychiatric comorbidities is essential 4
Normal developmental fears should be distinguished from pathological anxiety, and consideration of developmental factors is crucial 4
The American Academy of Child and Adolescent Psychiatry recommends the use of standardized screening tools, such as the Generalized Anxiety Disorder-7 (GAD-7), for the assessment of anxiety disorders in adolescents 4
The GAD-7 is a 7-item self-report scale with excellent validity, where scores ≥10 suggest moderate anxiety and scores ≥15 suggest severe anxiety, with a sensitivity of 89% and specificity of 82%, as recommended by the National Institute of Mental Health and American Academy of Family Physicians 5, 6
The GAD-2 (ultra-short version) is a good initial rapid screening tool, where a positive screen is defined as a score ≥ 3 points, according to the National Institute of Mental Health 6

A comprehensive treatment approach should include thyroid optimization, selective serotonin reuptake inhibitors (SSRIs), and cognitive behavioral therapy (CBT), with careful monitoring of thyroid function to prevent exacerbation of anxiety symptoms, as recommended by the American Psychiatric Association 1
Cognitive-behavioral therapy (CBT) is a first-line non-pharmacological treatment for anxiety, as recommended by the American Psychological Association 1
The American Academy of Child and Adolescent Psychiatry recommends SSRIs as first-line treatment for anxiety disorders and panic attacks, starting with a low dose and gradually increasing to minimize side effects 4
Beta-blockers (e.g., propranolol 10-20mg as needed) can be used to manage physical symptoms of panic attacks, according to the National Institute of Mental Health guidelines 1
The optimal target TSH range for most patients with Hashimoto's is in the mid-normal range (1-3 mU/L) to avoid overtreatment and exacerbation of anxiety symptoms, as recommended by the Endocrine Society 1
Referral to psychiatry should be considered for adolescents with moderate to severe anxiety, risk of self-harm, severe functional impairment, or poor response to initial interventions, with a GAD-7 score threshold of ≥10 for moderate to severe anxiety 4