Tiredness can negatively impact performance at work, family life, and social relationships. Fatigue has a reputation as a vague and difficult problem for doctors to investigate, and many people with fatigue do not report it to their doctor.
Doctors who are conscious of this take the problem seriously and attempt to determine an underlying cause. There are many reasons people become tired, and, consequently, there are many ways to rectify the situation.
- Fatigue is also known as tiredness, reduced energy, physical or mental exhaustion, or lack of motivation.
- Causes of fatigue can be psychological, physiological, and physical.
- To diagnose the reasons for fatigue, a doctor will ask questions and take a sleep history, and may perform a physical examination and blood and urine tests.
- Treatment is focused on the underlying cause of tiredness.
What is fatigue?
Fatigue and tiredness are common and can affect everyday life.
Simply put, fatigue is the feeling of being tired.
It is generally different from the sleepy feeling of drowsiness, or the psychological feeling of apathy, although these might both accompany fatigue.
Other terms to describe fatigue include:
- reduced or no energy
- physical or mental exhaustion
- lack of motivation
Fatigue is a common experience - all humans become tired. However, this is not usually due to disease. There are numerous medical and non-medical causes of fatigue, including personal dietary and lifestyle habits.
The following factors can contribute to fatigue, either alone or in combination:
- Psychological and psychosocial - stress, anxiety, and depression.
- Physical - anemia, diabetes, glandular fever, and cancer.
- Physiological - pregnancy, breast-feeding, inadequate sleep, and excessive exercise.
Some types of fatigue are not normally considered a medical problem, this includes tiredness as a result of:
- physical activity
- emotional stress
- lack of sleep
The National Institute on Aging lists the following lifestyle habits that can lead to tiredness and fatigue:
- staying up too late
- having too much caffeine
- drinking too much alcohol
- eating junk food
Some people are more likely than others to suffer from fatigue. For instance, women more often report fatigue. People who live in poverty and those with mental or physical illness are also more likely to present with fatigue.
Physical causes can lead to fatigue, along with psychological and physiological factors. The list of physical or medical causes is long, making it important to see a doctor for an accurate diagnosis based on an individual's personal and medical history.
The list of potential medical reasons for fatigue includes:
- obstructive sleep apnea
- sedative and antidepressant treatments
- iron deficiency
- kidney disease
- liver disease
- heart failure
- thyroid disease
- Addison's disease
- anorexia nervosa or other eating disorders
- arthritis, including rheumatoid arthritis
- autoimmune diseases such as systemic lupus erythematosus
- infection, especially long-term
- AIDS, tuberculosis, and mononucleosis
There is no single treatment for fatigue - because the management approach depends on the cause of the tiredness.
If the diagnostic process unveils no underlying medical explanation for the fatigue, the following lifestyle and dietary modifications may help resolve it:
- Improving sleep habits and ensuring adequate sleep.
- Exercising regularly and balancing rest and activity.
- Cutting out caffeine and drinking plenty of water.
- Eating healthy to avoid becoming overweight or underweight.
- Setting realistic expectations for workload and schedule.
- Taking time to relax, perhaps trying meditation or yoga.
- Identifying and dealing with stressors by, for example, taking time off work or resolving relationship problems.
- Avoiding the use of alcohol, nicotine, and illegal drugs.
For some people with fatigue, doctors may consider offering a referral for counselling or a talking therapy known as cognitive behavioral therapy (CBT).
Some doctors specialize in chronic fatigue syndrome (or myalgic encephalopathy) services, and these may be a suitable referral even for people who do not meet the criteria for this diagnosis. They will offer a consultant opinion for occupational reasons for fatigue, or may provide a structured, multidisciplinary approach to management, including supervised graded exercise therapy.
Doctors will ask a series of questions when diagnosing fatigue to determine the cause.
Fatigue is a difficult issue for doctors. It may be a physical problem rather than a psychological one.
The following conclusion from a research paper on psychological fatigue highlights the need for a partnership to be developed between doctor and patient for proper diagnosis.
"Patients consulting for tiredness are likely to report symptoms of psychological distress and attend more frequently than other patients.
They tend to view the problem as physical while their doctors view the problem as psychological. Having established that there is no physical problem, doctors may need to focus more on sharing ideas and explanations when patients complain of being 'tired all the time.'"
When patients present with fatigue, doctors will try to develop a more precise description of symptoms, typically by asking the following types of questions:
- Have you felt drowsy, or has the fatigue been more a feeling of weakness? - the answer can give clues to the diagnosis because drowsiness may be a symptom of a sleep disorder, while weakness may be a sign of a neuromuscular cause.
- During the past month have you often been bothered by feeling down, depressed, or hopeless? - positive answers may indicate depression.
- Has your fatigue developed gradually or suddenly?
- Does your tiredness come in cycles? - for example, depression is indicated if the fatigue is worst in the morning but persists all day, whereas fatigue associated with exercise suggests a neuromuscular issue.
- What are your concerns about the fatigue? What do you think may be the cause? - the doctor may be looking for a connection with any distressing life events, for example.
More general questions are designed to elicit information regarding psychological or lifestyle issues. There may be questions about relationships and any recent bereavements or upheavals related to employment or housing. The doctor may also ask about a patient's diet and exercise.
The doctor might take a 'sleep history' to work out whether a sleep disorder is leading to the fatigue:
- How much sleep do you get each night?
- Do you have trouble getting to sleep or do you wake up during the night?
- Has anyone told you that you snore?
- Has anyone noticed that you stop breathing for short periods of time during sleep?
These sleep history questions are designed to determine the sleep quality, quantity, patterns, and sleep routine.
The doctor may also examine a patient physically or check their mental state to find physical and mental causes. If no specific cause is indicated, there is a set of standard tests used to help narrow down the diagnosis. Based on the patient's complaints, these may include:
- full blood count
- erythrocyte sedimentation rate or C-reactive protein
- liver function tests
- urea and electrolytes
- thyroid stimulating hormone and thyroid function tests
- creatine kinase
- urine and blood tests for glucose
- urine test for protein
Chronic fatigue syndrome
Any tiredness that persists for a long time can be termed chronic, but medical papers and guidelines set chronic tiredness as being fatigue that lasts at least 6 months.
A diagnosis of chronic fatigue syndrome (CFS, also known as myalgic encephalopathy or ME) is made when tiredness persists for more than 4 months and cannot be explained by another diagnosis.
The person with CFS/ME must display one or more of the following symptoms:
- difficulty with sleeping
- muscle or joint pain - multi-site without evidence of inflammation
- painful lymph nodes
- sore throat
- cognitive dysfunction
- physical or mental exertion makes symptoms worse
- general malaise or flu-like symptoms
- dizziness or nausea
- palpitations in the absence of identified heart disease
A diagnosis of CFS/ME should be reconsidered if none of the following features is present:
- fatigue or malaise after exertion
- cognitive difficulties
- sleep disturbance
- chronic pain