Fatigue – UpToDate

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.

DDx

1. Psychogenic: depression, anxiety, Somatization disorder, life stresses,
2. Sleep: OSA, esophageal reflux, allergic rhinitis, psychologic causes
3. Endocrine: DM, hypothyroidism, apathetic hyperthyroidism, malnutrition / drug addiction, Hypercalcemia, pituitary insufficiency, adrenal insufficiency, CKD, hepatic failure
4. Infection: endocarditis, TB, mono, hepatitis, parasitic dz, HIV, CMV
5. CV: CHF, COPD
6. Inflammatory: Rheumatoid dz, SLE, PMR
7. Substance abuse / drugs
8. Neoplastic-hematologic: occult malignancy, severe Anemia
9. 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.

Hx:

• 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

PEx

• 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.

1. Hypnotics
2. Antihypertensives
3. Antidepressants
4. 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.

1. Acknowledge the patient’s complaints as real and potentially debilitating.
2. 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
3. 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:

1. unexplained fatigue > 6mo, not alleviated by rest and causes impact on lifestyle
2. +≥ 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

References:

• UpToDate 2015