From the Guidelines
When investigating tiredness, a thorough medical history and physical examination should be performed, followed by basic blood tests, including a complete blood count, thyroid function tests, and comprehensive metabolic panel, as recommended by 1.
Initial Assessment
The initial assessment of tiredness should include:
- A focused fatigue history, including onset, pattern, duration, and associated or alleviating factors
- Evaluation of disease status, including risk of recurrence and review of systems to determine if other symptoms substantiate suspicion for recurrence
- Assessment of treatable contributing factors, such as comorbidities, medications, alcohol/substance abuse, nutritional issues, and deconditioning
Laboratory Evaluation
Laboratory evaluation should be considered based on the presence of other symptoms, onset, and severity of fatigue, and may include:
- Complete blood count with differential to assess for anemia and other cell lines
- Comprehensive metabolic panel to assess electrolytes, hepatic, and renal function
- Endocrinologic evaluation, including thyroid-stimulating hormone (TSH) levels
- Other tests, such as vitamin levels, inflammatory markers, and cortisol levels, may be ordered based on clinical suspicion
Further Investigations
If initial tests are normal but symptoms persist, further investigations may include:
- Screening for sleep disorders, such as sleep apnea
- Testing for chronic infections, such as Epstein-Barr virus or HIV
- Checking inflammatory markers for autoimmune conditions
- Assessing mental health, including screening for depression and anxiety
- Referral to specialists, such as cardiologists, endocrinologists, or mental health professionals, may be necessary
Lifestyle Factors
Lifestyle factors, including diet, exercise patterns, alcohol consumption, and stress levels, should be thoroughly evaluated, as they often contribute significantly to fatigue, as noted in 1.
Stepwise Approach
The investigation process should be stepwise, starting with the most common causes of tiredness before proceeding to more specialized testing based on clinical suspicion, as recommended by 1.
From the Research
Investigations for Tiredness
- The diagnosis of fatigue can be guided by a comprehensive history and physical examination, including cardiopulmonary, neurologic, and skin examinations 2.
- Laboratory tests may be ordered to rule out underlying medical conditions, but results affect management in only 5 percent of patients 3.
- If initial laboratory results are normal, repeat testing is generally not indicated 3.
- Investigations beyond the history, physical examination, and simple laboratory tests are needed only in the presence of additional symptoms or findings 4.
- Watchful waiting and regularly scheduled follow-up can help prevent an excessive focus on somatic causes, leading to overdiagnosis 4.
Common Causes of Fatigue
- Sleep disorders and sleep-related disorders of breathing, depression, and excessive psychosocial stress are the most common causes of persistent fatigue 4.
- Anemia and other organic causes are rare, accounting for only 4.3% of cases 4.
- Previously undiagnosed cancer is a rare cause, accounting for only 0.6% of cases 4.
- Lifestyle issues, physical conditions, mental disorders, and treatment side effects can also contribute to fatigue 3.
Treatment and Management
- Treatment of fatigue should include a structured plan for regular physical activity, such as stretching and aerobic exercise 3.
- Cognitive behavior therapy, exercise therapy, and acupuncture may help with some of the fatigue associated with chronic conditions 2.
- Psychoeducative and psychotherapeutic approaches, as well as an individually adapted exercise program, can be beneficial for patients with fatigue 4.
- Patients with chronic fatigue syndrome should be educated about pacing their activity to not exceed their limited energy capacity 2.