“I am always so tired these days.” “I just don’t seem to have the energy I used to.” I’m exhausted by 8 o’clock at night.” Ring a bell? One of the commonest reasons for seeing a doctor is fatigue – tiredness that interferes with daily living and seems abnormal compared with others or with previous energy levels.
There are some serious medical reasons for this, but there are also many lifestyle issues which can result in incapacitating fatigue. The high level of heat and humidity in Singapore can sap energy and acclimatization is often only partial. Long work hours and the frequent socializing associated with an expat lifestyle contribute, as does loss of fitness if there is no time for an exercise program. The arrival of a baby can take its toll both by interrupting sleep or simply due to the extra workload. Even if a helper does the housework, just playing with a young child all day is more tiring than a full-time job. Frequent travel especially if changing time zones is another factor affecting many people here.
The most common pathological causes of fatigue are depression, thyroid disorder, iron deficiency and viral infection. Diabetes may also present in this way.
Depression is often insidious and may not necessarily produce intense sadness. Features such as loss of enjoyment in life, loss of libido, irritability, anxiety and sleeping difficulties may be more prominent, and fatigue is very often the most obvious feature. The stress brought on by an international move, separation from loved ones, enforced leaving of satisfying jobs, and the difficulty of living in a different environment without the support of close friends, can all help to precipitate an episode of depression. This is more likely if there is a family history or previous experience of depression. Symptoms may first appear after the birth of a child, either the first or any subsequent baby. Treatment has greatly advanced in recent years, with relief from symptoms resulting rapidly and often without side effects. Counseling can also be very helpful.
Both over- and underactivity of the thyroid gland can result in fatigue, and are more common in women. A family history of thyroid disease may be present. Hypothyroidism (underactivity) may produce weight gain, intolerance to cold, and dry hair and skin. Hyperthyroidism will often result in weight loss, tremor, and intolerance to heat. A blood test will reliably diagnose these conditions.
Dietary iron deficiency is becoming more common as we eat less and less red meat and more and more fibre. Red meat is still the best source of iron, although fish, chicken, egg yolk, pulses and green vegetables contain reasonable amounts. The problem with dietary fibre is that it binds iron in the intestine and prevents it from being absorbed. Women are at particular risk of iron deficiency due to regular blood loss from menstruation.
Diabetes is becoming an increasingly serious health problem world-wide as Western diets become adopted. Early mortality from associated cardiovascular disease, blindness, kidney failure and gangrene can all result from undiagnosed diabetes, which may have no distinct symptoms other than fatigue.
In some individuals, fatigue may persist despite exclusion of all the above causes. This may date from the time of a viral infection or commence without any obvious precipitant. Fatigue lasting at least 6 months, not due to any other medical condition, and significantly interfering with daily life, are the diagnostic criteria of chronic fatigue syndrome. A wide variety of treatments have been suggested for this, but the most effective have been shown to be a graded exercise program where physical activity is gradually increased day by day, and anti-depressants including St. John’s wort.