From the Guidelines
There are no specific laboratory tests that can diagnose anxiety disorders directly, but healthcare providers may order certain lab tests to rule out medical conditions that can mimic anxiety symptoms, such as thyroid function tests, complete blood count, and comprehensive metabolic panel, as suggested by the most recent guideline 1. When evaluating a patient with anxiety symptoms, it's essential to consider potential underlying medical conditions that may be contributing to their symptoms. According to the clinical practice guideline for the assessment and treatment of children and adolescents with anxiety disorders 1, medical conditions associated with anxiety include hyperthyroidism, caffeinism, migraine, asthma, diabetes, chronic pain/illness, lead intoxication, hypoglycemic episodes, hypoxia, pheochromocytoma, central nervous system disorders, cardiac arrhythmias, cardiac valvular disease, systemic lupus erythematosus, allergic reactions, and dysmenorrhea. Some studies have investigated the relationship between anxiety disorders and thyroid function, with mixed results. For example, a systematic review of 12 studies found that the prevalence of thyroid disorders in patients with anxiety disorders ranged from 2% to 39.3% 1. However, the quality of these studies varied, and the results should be interpreted with caution. In terms of laboratory tests, thyroid function tests (TSH, T3, T4) are commonly ordered to rule out thyroid disorders, which can present with anxiety-like symptoms 1. Other tests that may be ordered include complete blood count, comprehensive metabolic panel, and blood glucose levels to check for hypoglycemia. Additionally, tests for vitamin deficiencies (particularly B12 and D) might be ordered, as these can affect mood and anxiety. It's essential to note that anxiety disorders are primarily diagnosed through clinical evaluation of symptoms, medical history, and psychological assessments rather than laboratory findings. Laboratory tests are used to rule out underlying medical conditions that may be contributing to the patient's symptoms, rather than to confirm a diagnosis of anxiety disorder.
From the Research
Laboratory Tests for Anxiety
Some laboratory tests may be relevant in the diagnosis and management of anxiety, particularly when underlying medical conditions are suspected. These tests include:
- Complete blood cell count (CBC) 2
- Complete blood chemistry analysis 2
- Erythrocyte sedimentation rate (ESR) 2
- Urinalysis 2, 3, 4
- Serum glucose 2
- Blood urea nitrogen (BUN) 2
- Creatinine 2
- Electrolyte panel (including sodium, potassium, calcium, and magnesium) 3, 4
- Vitamin B12 level 5, 2
Rationale for Laboratory Tests
These laboratory tests can help identify underlying medical conditions that may be contributing to anxiety symptoms, such as:
- Electrolyte imbalances (e.g., hyponatremia, hypomagnesemia) 3, 4
- Vitamin B12 deficiency 5
- Diabetes or kidney disease 2
- Infections or inflammatory conditions 2
Special Considerations
Certain populations may benefit from more extensive laboratory evaluation, including: