The difference between fatigue and everyday tiredness
Fatigue is a common complaint made to primary care providers by both the general population and by individuals with certain chronic conditions including chronic heart failure,1 chronic kidney disease,2 coeliac disease3 and inflammatory bowel disease (IBD).4 Studies in the UK and the USA found that up to 24% of individuals reported fatigue as a major problem in a primary care setting.5 In a study of 220 patients, fatigue was shown to be up to three times more likely to be reported by women than men.6
It is important to distinguish between everyday tiredness, that can be managed, and fatigue that can have a serious and continuing impact on an individual’s quality of life.
Everyday tiredness is short-term and generally resolves with extra exercise, rest, and/or sleep.7 It can be caused by:
- Lack of, or excessive exercise5,7–9
- Lack of sleep10
- Excess caffeine11 or alcohol intake12
- Colds or flu7
In contrast, fatigue is more serious, and can affect the patient’s physical, emotional, social and economic wellbeing. Fatigue has been characterized as long-term mental and/or physical exhaustion that occurs without any great physical exertion.13 Patients may describe fatigue as feeling “exhausted”, “listless”, “washed out” or “cranky” and may also associate it with diminished performance at work or increased difficulty in performing routine daily tasks.14
Fatigue is a complex symptom because it can be caused by many different underlying conditions, including:
- Iron deficiency, with or without anaemia15
- Anaemia due to other reasons, such as low levels of vitamin B12 or folate16
- Hormonal conditions such as hypothyroidism and diabetes17
- Chronic fatigue syndrome, also called myalgic encephalomyelitis (ME)5
- Depression5,18 and sleep problems17
- Iron overload, known as haemochromatosis19
Due to this it is important that physicians investigate the underlying cause of the fatigue, for example by performing blood tests for iron deficiency.
How can fatigue be measured?
It can be challenging to measure fatigue in a clinical context as fatigue is, by its nature, a subjective experience.6 The use of clinically verified fatigue questionnaire tools can enable doctors to determine the level of a patient’s fatigue.
The Functional Assessment of Chronic Illness Therapy-Fatigue scale (FACIT-F scale) is one example of a diagnostic questionnaire for fatigue that has been validated in multiple patient populations, including the general population.20 The FACIT-F scale captures the patient’s perspective of their level of fatigue and its impact on their life based on the previous seven days.20 It consists of 13 questions that only take 2-3 minutes for the average patient to complete.20 If the questionnaire is completed on multiple occasions the scale can also indicate how the patient’s fatigue changes or improves over time.
Other short form options to assess fatigue include the Brief Fatigue Inventory21 and the Daily Fatigue Impact Scale.22 Alternatively, other longer-form questionnaire options are also available. These include the Piper Fatigue Scale and the Multidimensional Assessment of Fatigue (MAF), a revised shorter version of the Piper Fatigue Scale.13,23
You can use irondeficiency.com’s user-friendly, interactive Fatigue Survey, based on the FACIT-F scale to record your patients’ levels of fatigue. Patients can also complete the questionnaire in their own time and discuss reports with you during consultations.