06. Approach to Fatigue

Resident Editors:  Scott Goldberg, MD

Faculty Editor:  Katherine Julian, MD

Background

  • The most important question to ask a patient when they say they have fatigue is – “what do you mean by fatigue?”
  • Patients may say they are fatigued when they have: difficulty or inability initiating activity (perception of generalized weakness); reduced capacity maintaining activity (easy fatigability); difficulty with concentration, memory, or emotional stability (mental fatigue); sleepiness or tiredness; weakness; or shortness of breath. 
  • Primary complaint in 5-7% of primary care visits
  • Diagnosis made in <50% of patients; most cases multifactorial
  • Duration:
    • Recent: < 1 month ,
    • Prolonged: 1 - 6 months
    • Chronic > 6 months
  • Extremely broad differential diagnosis that is best organized by an organ/system approach

Differential Diagnosis

  • Psychiatric (depression, anxiety, somatization disorder, substance use)
  • Sleep disorders (OSA, OHS, narcolepsy, insomnia)
  • Pharmacologic (B-blockers, antihistamines, narcotics, muscle relaxants, sleep aids, benzodiazepines, antidepressants)
  • Cardiac (congestive heart failure)
  • Pulmonary (chronic lung disease)  
  • Endocrine (hypothyroidism, DM, pituitary insufficiency, hypercalcemia, adrenal insufficiency)
  • Renal (chronic renal failure)
  • Liver (chronic liver disease)
  • Infectious (chronic infections such as endocarditis, tuberculosis, mononucleosis, hepatitis, parasitic disease, HIV infection, CMV)
  • Rheumatologic
  • Neoplastic/hematologic (malignancy, anemia)
  • Neurologic (multiple sclerosis)
  • Gastrointestinal
  • Idiopathic (i.e. chronic fatigue syndrome)
    • Chronic Fatigue Syndrome (CFS):
      • Consider a diagnosis of CFS if these 3 criteria are met:
        • The individual has severe chronic fatigue for 6 or more consecutive months that is not caused by ongoing exertion or other medical conditions associated with fatigue
        • The fatigue significantly interferes with daily activities and work

The individual concurrently has four or more of the following eight symptoms: post-exertion malaise lasting more than 24 hours; unrefreshing sleep; significant impairment of short-term memory or concentration; muscle pain; multi-joint pain without swelling or redness; headaches of a new type, pattern, or severity; tender cervical or axillary lymph nodes; a sore throat that is frequent or recurring 

Evaluation

  • History
    • History is the most important part of the evaluation of a patient presenting with fatigue
    • Ask patient to describe fatigue in their own words
    • Ask about:
      • Recent life stressors
      • Symptoms of depression/anxiety (perform PHQ-9)
      • Symptoms of disordered sleep (especially OSA)
      • New medications or substance use
      • Signs of bleeding, dyspnea on exertion, weakness
    • Complete ROS focusing on each organ system: chronic kidney disease, cirrhosis, heart failure, lung disease, infections, joint pains, constitutional symptoms  
  • Physical exam
  • Laboratory workup
    • Laboratory evaluation rarely reveals a cause for fatigue
    • If there is not an obvious cause of fatigue, appropriate to get CBC, TSH, CMP, ESR
    • Consider HIV/Hep C in at-risk populations
    • Order sleep study if high suspicion for OSA
    • All patients should have age-appropriate cancer screening
    • Other lab testing not recommended unless history is suggestive

Treatment

  • Treat underlying organic and psychiatric illness as appropriate
  • Medications that may be causing fatigue should be replaced or discontinued, if possible
  • When initial evaluation for fatigue is non-diagnostic, the provider should acknowledge the patient’s symptoms. Provide reassurance that there will be active ongoing management in the form of symptom-focused treatment and plan for observed follow up.
  • In all patients with chronic fatigue syndrome or idiopathic fatigue, review principles of good sleep hygiene. Recommend low-intensity physical activity and consider cognitive behavioral therapy (CBT).

References

Cornuz J, Guessous I, Favrat B. Fatigue: a practical approach to diagnosis in primary care. CMAJ. 2006;174(6):765-7.

Hamilton W, Watson J, Round A. Investigating fatigue in primary care. BMJ. 2010;341:c4259.

Rosenthal et al.  Fatigue: An Overview.  American Family Physician. 2008; 78 (10); 1173-1179.

Stern SC, Cifu AS, Altkorn D. Stern S.C., Cifu A.S., Altkorn D Eds. Scott D.C. Stern, et al.eds. Symptom to Diagnosis: An Evidence-Based Guide, 3e New York, NY: McGraw-Hill; 2014.

Wright J, O'Connor KM. Fatigue. Med Clin North Am. 2014 May;98(3):597-608.