Physical fatigue is often associated with lack of oxygen supply to the cells of the body. Thus, fatigue may result due to a decrease in the pumping action of the heart, a decrease in the oxygen-carrying capacity of the blood, or a decrease in oxygenation of the blood due to a lung problem.
The cause of fatigue may vary from something very mild to a very serious illness like cancer. Nearly any health condition can result in fatigue to various degrees. Listed below are some of the common causes of chronic fatigue:
► Thyroid disorders: Thyroid disorders are common causes of fatigue in women. Both high and low thyroid hormone levels leave the patient fatigued by the end of the day. Low thyroid levels result in lethargy and weight gain, while high thyroid hormone levels result in palpitations and weight loss.
► Anemia: The body requires oxygen for all the cellular functions, which is carried by the red blood cells. Anemia, a condition where the total number of red blood cells is low, results in fatigue. The patient also appears pale.
► Heart failure: Heart conditions like heart failure result in reduced blood supply to the different parts of the body. The patient therefore feels fatigued, sometime even after mild activity. The patient may show symptoms of breathlessness and swelling of feet.
► Hepatitis: Hepatitis, a liver infection commonly associated with jaundice, leaves the patient tired and drowsy. The skin and eyes appear yellow. The urine also appears deep yellow in color.
► Lung disease: Lung diseases cause decreased oxygenation of blood, and result in fatigue. The patient shows the presence of other symptoms like cough and breathlessness.
► Sleep apnea: Sleep apnea is a condition where a person snores and stops breathing temporarily at night. Thus, the patient is unable to get a full night sleep and is totally tired the next day.
► Persistent pain: A persistent feeling of pain due to conditions like arthritis and nerve inflammation cause extreme fatigue.
► Cancer: Cancer is one of the most serious causes of fatigue. If the cause of fatigue cannot be pinpointed, it is better to evaluate the person to rule out cancer. Cancer is commonly associated with sudden weight loss.
► Medications: It is necessary to evaluate the medication intake in patients complaining of fatigue. Drugs used for high blood pressure like beta blockers can affect heart function and result in fatigue. Similarly, sedatives could also cause daytime fatigue.
► Psychological disorders: Psychological disorders like depression and anxiety may result in mental fatigue and difficulty in concentrating.
► Other conditions: Other conditions that could be associated with fatigue are autoimmune diseases, infections, kidney diseases, and muscle or nerve diseases.
► Chronic fatigue syndrome: Chronic fatigue syndrome is a feeling of severe tiredness that lasts for at least 6 months and cannot be attributed to any underlying cause. The fatigue is not relieved by bed rest. The diagnosis is made by ruling out other possible causes of fatigue.
Frequently Asked Questions (FAQs)
1. Which doctor should I visit in case I suffer from fatigue?
You should visit your general practitioner or family doctor in case you suffer from fatigue.
2. Which are some of the tests that can be done to diagnose the cause of fatigue?
After obtaining a history and conducting an examination of the patient, some of the tests that may be advised to the patient include a complete blood count, erythrocyte sedimentation rate, liver, kidney and thyroid function tests, blood glucose estimation, and tuberculin test to rule out tuberculosis. Questionnaires may be given to the patient to rule out psychiatric problems. Further testing may be required based on the probable diagnosis.
References:1. Current Medical Diagnosis and Treatment 2012
Latest Publications and Research on Chronic Fatigue Symptom EvaluationMeta-analysis investigating post-exertional malaise between patients and controls. - Published by PubMed
Personalised relaxation practice to improve sleep and functioning in patients with chronic fatigue syndrome and depression: study protocol for a randomised controlled trial. - Published by PubMed
Study protocol and rationale for a prospective, randomized, double-blind, placebo-controlled study to evaluate the effects of Ashwagandha (Withania somnifera) extract on nonrestorative sleep. - Published by PubMed
Longitudinal relationship between onset of physical symptoms and functional impairment. - Published by PubMed
Fatigue in the general population: German normative values of the EORTC QLQ-FA12. - Published by PubMed