Swollen feet — medically called oedema — can make life miserable. Shoes and slippers don’t fit — they are tight and uncomfortable and sometimes impossible to put on. The feet feel like dead weights, and walking becomes a Herculean task. It is much easier to simply sit. But inactivity makes the swelling worse, and the sufferer is caught in a vicious cycle of swelling-inactivity-more swelling.
The fluid that accumulates and causes oedema leaks from tiny blood vessels called capillaries. This can occur as a result of increased pressure, damage to the vessels or a fall in the protein concentration of the blood. As soon as the body senses that the capillaries are leaking, compensatory mechanisms come into play and fluid is retained in the body by the kidney. The amount of fluid circulating in the body therefore increases. This, in turn, causes the capillaries to leak more. This fluid from the capillaries leaks into the surrounding tissue, causing the swelling. At least five litres of fluid need to be retained before actual swelling appears.
Feet swell before any other part of the body. This is because the hydrostatic pressure on the blood vessels of the lower limbs are, by virtue of gravity, one metre more than the pressure on the face. Also, when we sit and stand, our feet are at a lower level than the heart and this aggravates the problem.
To demonstrate oedema, press firmly with your forefinger and maintain the pressure for 10 seconds. A persistent dimple like depression indicates the presence of oedema.
However, swollen feet do not always indicate disease. Overweight individuals may develop some amount of swelling at the end of a stationery day. (Fat is fluid at body temperature). This can be normal. The swelling can extend up to the knees.
Salt also causes fluid retention. If you consume a lot of salty snacks and pickles, the kidney is not able to handle the sodium overload and fluid is retained.
Women are more prone to develop oedema than men. The female hormones oestrogen and progesterone cause fluid retention. Women tend to “swell up” during the pre-menstrual period, pregnancy and if they are on hormones, either as oral contraceptive pills or as part of hormone replacement therapy (HRT). This can extend to the hands, making finger rings tight. The face may also appear puffy. This type of oedema disappears spontaneously in a few days once menstruation occurs, the baby is born or the hormones discontinued.
Oedema can be a side effect of prescribed medication like nifedepine, amlodepin and other anti-hypertensives. Medicines for pain belonging to the non-steroidal anti-inflammatory drugs (NSAIDs) group can also cause fluid retention. Some like diclofenac may damage the kidneys. If you develop swelling while on medication, consult your doctor.
At times, oedema can be the first sign of a serious underlying medical condition. If the heart is unable to pump blood efficiently, blood can accumulate in the capillaries of the legs, ankles and feet, causing oedema.
The liver regulates the protein content of the blood. It is also responsible for adjusting the hormones and chemicals that regulate the fluid content of the body. The organ can become damaged as a result of alcoholism, hepatitis B infection or other diseases. This injury results in scar formation and is called cirrhosis. Fluid can then accumulate in the legs and abdomen. But two of the causal factors can be prevented — don’t drink excessively and take your hepatitis B immunisations.
Damaged kidneys cannot excrete excess fluid. The oedema then occurs typically around the legs and eyes. Kidney damage can occur for a variety of reasons. Preventable causes are uncontrolled, neglected diabetes and hypertension.
The veins in the leg may be damaged or weak. Sometimes the valves in these veins — which prevent back flow of blood — may be inefficient. Chronic venous insufficiency and varicose veins can result in swelling.
Excess fluid from tissues is cleared by the lymphatic system. These drain into lymph nodes and eventually into the large veins. Infections like filaria can damage the lymphatic system. The nodes can be infiltrated by cancerous deposits. The nodes may have been removed or damaged during surgery. All this can result in swelling. Usually this is present in any one limb and not symmetrically on both sides of the body.
Always keep in mind:-
• Oedema can be treated if the causal factor is removed
• Reduce weight if the BMI (body mass index or weight divided by height in metre squared ) is more than 23
• Walk, jog or swim for 40 minutes a day
• Try to move the legs every half hour during the day
• Do not add extra salt to food and avoid salty snacks
• Keep the feet elevated
• Use elastocrepe bandages or compression stockings on affected limbs
• Do not consume NSAIDs unnecessarily
• Seek medical advice immediately for filaria
• Use diurectics to get rid of fluid only if prescribed by a doctor
• Control diabetes and hypertension.
Source: The Telegraph (Kolkata, India)