Fatigue can be manifested as
- difficulty or inability initiating activity (perception of generalized weakness);
- reduced capacity maintaining activity (easy fatiguability); and
- difficulty with concentration, memory, and emotional stability (mental fatigue)
- Fatigue should be distinguished from somnolence, dyspnea, and muscle weakness
Patients with organ-based medical illness often associate their fatigue with activities they are unable to complete. In contrast, patients with fatigue that is not organ-based are tired all the time; their fatigue is not necessarily related to exertion, nor does it improve with rest.
1 In all patients complaining of fatigue, include depression in the differential diagnosis.
- Psychogenic: depression, anxiety, Somatization disorder, life stresses,
- Sleep: OSA, esophageal reflux, allergic rhinitis, psychologic causes
- Endocrine: DM, hypothyroidism, apathetic hyperthyroidism, malnutrition / drug addiction, Hypercalcemia, pituitary insufficiency, adrenal insufficiency, CKD, hepatic failure
- Infection: endocarditis, TB, mono, hepatitis, parasitic dz, HIV, CMV
- CV: CHF, COPD
- Inflammatory: Rheumatoid dz, SLE, PMR
- Substance abuse / drugs
- Neoplastic-hematologic: occult malignancy, severe Anemia
- Idiopathic dx by exclusion: idiopathic chronic fatigue, CFS, fibromyalgia
2 Ask about other constitutional symptoms as part of a systematic approach to rule out underlying medical causes in all patients complaining of fatigue.
- Onset – abrupt or gradual, related to event or illness?
- Duration and daily pattern, Course – stable, improving or worsening?
- Factors that alleviate or exacerbate symptoms
- Impact on daily life – ability to work, socialize, participate in family activities & Accommodations that patient/family has made to adjust to fatigue symptoms
- Sleep: quantity & quality & whether or not sleep improves symptoms
- Thyroid symptoms
- Social: EtOH, drugs, medications
Red flags (constitutional symptoms):
- Fever, weight loss, night sweats
- neurological deficits, ill-appearing
Screening for psychiatric disorders
- depression, anxiety disorders
- somatoform disorders
- substance abuse
- victims of domestic violence
- General appearance: level of alertness, psychomotor agitation or retardation, grooming
- Presence of lymphadenopathy
- Evidence of thyroid disease: goiter, thyroid nodule, ophthalmologic changes
- Cardiopulmonary examination: signs of congestive heart failure and chronic lung disease
- Neurologic examination:
- muscle bulk, tone, and strength;
- deep tendon reflexes;
- sensory and cranial nerve evaluation
3 Exclude adverse effects of medication as the cause in all patients complaining of fatigue.
- Drug abuse and drug withdrawal / EtOH
4 Avoid early, routine investigations in patients with fatigue unless specific indications for such investigations are present.
Extensive laboratory evaluation in the absence of a positive history or physical examination are of little diagnostic utility in the evaluation of the fatigued patient
Reasonable initial laboratory studies to obtain include:
- Complete blood count with differential
- Chemistry screen (including electrolytes, glucose, renal and liver function tests)
- Thyroid stimulating hormone
- Creatine kinase, if pain or muscle weakness present
Screen for HIV / Hep C
ESR in older pt to r/o polymyalgia rheumatica or giant cell arteritis
5 Given patients with fatigue in whom other underlying disorders have been ruled out, assist them to place, in a therapeutic sense, the role of their life circumstances in their fatigue.
- Acknowledge the patient’s complaints as real and potentially debilitating.
- Act as a guide in establishing therapeutic goals:
- Accomplishing the activities of daily living
- Returning to work
- Maintaining interpersonal relationships
- Performing some form of daily exercise
- Effective Tx: cognitive behavioral therapy (CBT) and graded exercise therapy
Other measures that may be useful include:
- Provision of general sleep hygiene advice and discouraging over-sleeping
- Provision of patient education brochures and other materials, discussion of various aspects of chronic fatigue, and referral to support groups
- Iron therapy in nonanemic patients with low serum ferritin may improve symptoms of fatigue
6 In patients whose fatigue has become chronic, manage supportively, while remaining vigilant for new diseases and illnesses.
- Establishing a trusting clinician-patient relationship and defining appropriate therapeutic goals is important
- Brief regularly scheduled appointments preferred over prn appointments to monitor progress
Chronic Fatigue Syndrome (CFS) Dx:
- unexplained fatigue > 6mo, not alleviated by rest and causes impact on lifestyle
- +≥ 4 associated symptoms:
- Impairment of short-term memory or concentration causing a ↓ in function
- Sore throat
- tender cervical or axillary LN
- Muscle pain
- Polymyalgia: Multi-joint pain with no swelling or redness
- New headache
- unrefreshing sleep
- Post-exertional malaise >24hr
- UpToDate 2015