12. Fatigue

Question 1

Describe: Fatigue (4)

Answer 1

• Fatigue is defined as a state of extreme weariness.
• It is a symptom that is associated with many medical and psychiatric conditions.
• We will focus on medical, physical, and psychiatric conditions that present fatigue as the primary complaint and consider modifiable life changes that can contribute to decreasing overall fatigue.
• It is thought that there are many causes of fatigue that can easily be modified. It is important to ask about things such as sleep disturbances and lifestyle issues as causes of fatigue if no other cause can be found.

Question 2

Name DDX of fatigue (7)

Answer 2

• Chronic diseases
  
  • Neurologic
  • Cardiopulmonary
• Infectious
• Endocrine/metabolic
• Hematologic/neoplastic
• Pharmacologic
  
  • Hynotics /sedatives
  • Antidepressants
  • Anti hypertensives
  • Substance use
  • Antipsychotics
• Psychiatric
  
  • Depression
  • Anxiety
  • Somatization disorder
• Idiopathic
  
  • Chronic fatigue syndrome
  • Fibromyalgia

Question 3

Describe HX and physical exam: Fatigue (3)

Answer 3

• It is important to do a complete history and physical exam with a presentation of fatigue.
• Be sure to compile a list of medications that a patient is taking during the initial visit, as this may be the main cause of fatigue
• Do not forget to ask about sleep disturbances and lifestyle issues

Question 4

Describe investigations: Fatigue (9)

Answer 4

• The following investigations can be performed at the initial visit:
  
  • CBC
  • electrolytes
  • renal function tests
  • liver function tests
  • thyroid function tests
  • fasting plasma glucose
  • lipid panel
  • testing for syphilis and HIV.
  • These may be repeated as indicated clinically.
• Other, more focused investigations may be indicated according to your history and physical exam.

Question 5

Describe diagnosis: Fatigue (3)

Answer 5

• This may be a working Dx after the history, physical exam, and initial investigations.
• If there is an easily modifiable cause for fatigue, you can ask/suggest the patient to work on that cause first before investigating further.
• Be sure to consider fatigue as a symptom within another DSM-5 Dx such as:
  
  • MDD
  • Generalized anxiety disorder
  • Caffeine withdrawal
  • Stimulant withdrawal

Question 6

Describe management: Fatigue (2)

Answer 6

• The management principle is to treat the underlying cause of fatigue.
• As mentioned previously, this may be a stepwise approach in modifying the easily modifiable agents first (i.e., iron-deficient anemia) and then working on the more difficult causes of fatigue (i.e., chronic disease).