WHAT ARE THE CAUSES OF FATIGUE?
Why do I feel fatigued when I am physically a healthy person? Fatigue is the term used to define a physical or mental state of extreme tiredness and lack of energy. It can’t be related to common states of feeling sleepy or drowsy. Though sleepiness may be a symptom of fatigue it essentially does not mean you are fatigued. A fatigued person can’t find enough energy or motivation to do anything. (1)
Fatigue can be a result of variety of causal physiological and psychological factors. Physiological factors include physical health conditions, medication and lifestyle factors.
Our lifestyles play a defining role in determining our physical and mental health. The lifestyles one adopts can turn out to be a possible risk factor for onset of fatigue both physical and psychological. A study conducted on about 8833 people in America described their lifestyle as the causal factor of fatigue in them. Out of this population, fatigue was found more prevalent in men who were overweight and physically inactive.
The study suggested that these factors of being physically inactive and overweight can be modified. Modifying lifestyles towards being more active and healthy can prevent or in the least reduce the development of fatigue. More over this targeted intervention of change in lifestyle can counter the psychological risks of fatigue development as well. (2)
Moreover, physical exertion, lack of sleep, periods of emotional stress, grief, consuming too much caffeine, using illicit drugs and not eating properly are major causal factors towards fatigue.
Many medical conditions can cause fatigue. Conditions like anemia, arthritis, fibromyalgia, chronic fatigue syndrome, infections such as flu and cold, Addison’s disease- a disorder that can affect your hormone levels, hyperthyroidism, hypothyroidism, insomnia, anorexia or eating disorder, depression, autoimmune disorders, COPD, diabetes, liver and kidney diseases.
While it is normal for anyone to feel tired after physical exertion patients who are anemic most often experience fatigue even after shorter periods of activity. This happens because their red blood cells become deprived of oxygen.
Iron and physical energy go hand in hand. Iron in blood is important for formation of Hemoglobin, the oxygen carrying entity in red blood cells. Iron also influences many functions of mitochondria that generates ATP the main units of energy.
Arthritis is one of the most common causes of reported fatigue cases. This may be due to overall health status of the patient and also pertaining to the work dysfunction. Fatigue in arthritic patients, as common as it is, is a disabling factor. Patients often define their fatigues as a hurdle, adversely affecting their quality of life.
CHRONIC FATIGUE SYNDROME:
Also known as “Myalgic Encephalomyelitis” in books of science, the chronic fatigue syndrome is one of the most distressing causes of fatigue which is not relieved by rest. The illness is characterized by at least a six months period of agonizing fatigue and a group of additional symptoms.
The exact cause of chronic fatigue syndrome is still unknown. However, it can be developed suddenly, in most patients, after a physical or emotional trauma, any flu like infection or following a surgery.
Many infectious illnesses such as Lyme disease and mononucleosis can be casual factors of chronic fatigue syndrome. Researchers have found the people with chronic fatigue syndrome sometimes have abnormalities of brain, particularly its parts such as pituitary gland and hypothalamus- part of brain which regulates hormones. (3)
Fatigue is one of the major symptoms of Addison’s disease. Addison’s disease occurs when the adrenal cortex of adrenal glands- the glands present on top of kidney, is damaged. Adrenal glands regulate hormonal functions.
Addison’s disease causes reduced production of cortisol which regulates body’s reaction to stress and aldosterone which regulates sodium and potassium levels in body. (4)
EATING DISORDER/ ANOREXIA:
One of the telltale symptoms of Anorexia or eating disorder is fatigue. Anorexia is a potentially life-threatening complication of malnutrition according to F.E.A.S.S Eating Disorder Glossary. Anorexic people tend to deprive their bodies of its basic energy source, food. Due to deprivation of sufficient nutrition the body experiences severe physical and mental fatigue and tiredness.(5)
When the kidney’s functions are compromised by either chronic kidney diseases or kidney stones, it leads to concentration of toxins and impurities in the blood. Also people with chronic liver disease suffer from anemia at the hands of lack of production of erythropoietin- a hormone that plays a key role in production of red blood cells. (6)
Fatigue constitutes one of the most frequent complaints in liver disease patients. The prevalence of fatigue in liver patients varies from individual to individual. About 65%-85% of patients with cholestasis liver disease experience fatigue. While the prevalence in hepatitis patients is not clearly known yet. (7)
It's not uncommon for people with chronic obstructive pulmonary disease (COPD) to experience fatigue. COPD reduces airflow into your lungs, making breathing difficult and labored. It also reduces the oxygen supply your whole body receives. Without enough oxygen, your body will feel tired and exhausted. (8)
Fatigue is a nearly-universal symptom of hypothyroidism (an underactive thyroid), occurring as a result of the decrease in thyroid hormone production. One noticeable sign that your thyroid levels aren't properly regulated may be bone-numbing fatigue. (9)
Fatigue and psychological morbidity are moderately correlated. Women and men both are susceptible to fatigue associated to psychological factors. However, women reportedly have more complaints of fatigue due to psychological factors, compared to men. (10)
There is a strong relation between fatigue and depression. Depression is equally affecting both and male and female population. It wears the sufferer’s body by subjecting it to constant pressure and stress. This leads to patient’s lack of will to improvement. The constant feeling of unworthy and loss of positive outlook puts the patient under both physical and mental fatigue.(11)
Insomnia is a sleep disorder in which you have trouble falling and/or staying asleep. The condition can be short-term (acute) or can last a long time (chronic). It may also come and go. This constant and ongoing push and pull of mind and body distresses the body to a level where the tiredness can no longer be treated with rest. This state is fatigue, very common in insomniac individuals. (12)
1. Fatigue: Causes, Diagnosis, Treatment & More [Internet]. Healthline. [Cited 2020 Jun 22]. Available from: https://www.healthline.com/health/fatigue
2. Bültmann U, Kant Ij, Kasl SV, Schröer KAP, Swaen GMH, van den Brandt PA. Lifestyle Factors as Risk Factors for Fatigue and Psychological Distress in the Working Population: Prospective Results from the Maastricht Cohort Study. J Occup Environ Med. 2002 Feb;44(2):116–124.
3. Publishing HH. Chronic Fatigue Syndrome [Internet]. Harvard Health. [Cited 2020 Jun 22]. Available from: https://www.health.harvard.edu/a_to_z/chronic-fatigue-syndrome-a-to-z
4. Addison’s Disease [Internet]. Healthline. [Cited 2020 Jun 22]. Available from: https://www.healthline.com/health/addisons-disease
5. 5 Anorexia Symptoms You Shouldn’t Ignore | Betterhelp [Internet]. [Cited 2020 Jun 22]. Available from: https://www.betterhelp.com/advice/eating-disorders/5-anorexia-symptoms-you-shouldnt-ignore/
6. 10 Signs You May Have Kidney Disease [Internet]. National Kidney Foundation. 2014 [cited 2020 Jun 22]. Available from: https://www.kidney.org/news/ekidney/august14/10_Signs_You_May_Have_Kidney_Disease
7. Swain MG. Fatigue in liver disease: Pathophysiology and clinical management. Can J Gastroenterol. 2006 Mar;20(3):181–8.
8. Paddison JS, Effing TW, Quinn S, Frith PA. Fatigue in COPD: association with functional status and hospitalisations. Eur Respir J. 2013 Mar 1;41(3):565–70.
9. Hypothyroidism - Symptoms and causes [Internet]. Mayo Clinic. [Cited 2020 Jun 22]. Available from: https://www.mayoclinic.org/diseases-conditions/hypothyroidism/symptoms-causes/syc-20350284
10. Pawlikowska T, Chalder T, Hirsch SR, Wallace P, Wright DJM, Wessely SC. Population based study of fatigue and psychological distress. BMJ. 1994 Mar 19;308(6931):763–6.
11. Fuhrer R, Wessely S. The epidemiology of fatigue and depression: a French primary-care study. Psychol Med. 1995 Sep;25(5):895–905.
12. Richter K, Acker J, Adam S, Niklewski G. Prevention of fatigue and insomnia in shift workers—a review of non-pharmacological measures. EPMA J. 2016 Aug 2;7(1):16.