How is it Diagnosed?
Diagnosing fatigue involves a multifactorial approach due to its nonspecific and
subjective nature. The clinician begins with a comprehensive history-taking session to
understand the duration, pattern (constant or intermittent), severity, and impact of the
fatigue. Associated symptoms—like sleep disturbances, mood changes, weight
fluctuations, pain, or shortness of breath—are also noted.
A thorough physical examination is performed to identify any clinical signs of systemic
illness, such as pallor (anemia), thyroid enlargement, lymphadenopathy, or signs of
depression. Lifestyle factors like diet, exercise, alcohol use, and sleep hygiene are
evaluated.
Blood tests are a central component. A complete blood count (CBC) helps detect
anemia or infections. Thyroid function tests (T3, T4, TSH) assess for hypothyroidism.
Blood glucose, liver and kidney function tests, and electrolyte panels are used to rule
out metabolic causes. Vitamin B12 and D levels may be checked for nutritional
deficiencies.
If psychological causes are suspected, screening for depression, anxiety, and stress is
conducted using standardized questionnaires like the PHQ-9 or GAD-7.
Polysomnography may be ordered if sleep disorders like sleep apnea are suspected.
Further diagnostic tests depend on suspected underlying conditions. Chronic fatigue
syndrome is diagnosed after ruling out other causes and following established criteria.
A multidisciplinary approach is often needed to determine the root cause and manage
fatigue effectively.