Losing weight is a good thing for most people, but not necessarily when you are diagnosed with chronic obstructive pulmonary disease (COPD).
As the disease is closely related to obesity, many COPD patients are actually overweight when they first receive their diagnosis. However, in the advanced stages of the disease, some patients may find themselves wasting away.
The severe weight loss caused by COPD can make it even harder for patients to cope with the breathing difficulty and the extreme fatigue associated with the disease.
A COPD patient can expend five to 10 times more energy than a healthy person for basic activities like breathing, so getting enough fuel from food becomes critical in managing the disease, explains Dr Ong Thun How, Senior Consultant at the Department of Respiratory and Critical Care Medicine, Singapore General Hospital (SGH).
“Malnutrition and weight loss are common complications of COPD so it’s important for patients to maintain a healthy body weight to improve their prognosis and survival,” says Dr Ong.
COPD essentially refers to lung function which has been damaged, usually by heavy smoking, in someone who is genetically susceptible to the disease. There are two forms of COPD:
Chronic bronchitis is a condition in which the lining of the two bronchial tubes (lung airways) becomes inflamed and thickens. Mucus forms, making it difficult for the airways to carry air into the lungs.
Emphysema is the failure of the tiny air sacs or alveoli to oxygenate the lungs, resulting in shortness of breath. This happens when the air sacs, found in each lobe of the lung, are damaged and lose their elasticity to expand and contract.
Many patients have overlapping features of both chronic bronchitis and emphysema. In both cases, the lung damage results in narrowing of the airways, thus restricting the flow of air in and out of the lungs.
What causes weight loss in COPD patients?
The following factors can cause people with COPD to lose weight:
- Burning up more energy than normal even for the simplest physical activity
Even normal activities like dressing and washing will require high-energy output, resulting in weight loss.
- Taking anti-inflammatory medications such as inhaled corticosteroids to manage COPD symptoms
Corticosteroids may cause side effects such as a sore mouth and mood changes which may dampen appetite. They also weaken bones and muscle tissues.
- Feeling too depressed to eat
The debilitating effects of COPD on everyday life can affect the patient’s emotional and psychological well-being – and interest in food.
Symptoms of COPD
COPD is an irreversible disease which becomes progressively worse if left untreated. People with very severe COPD feel breathless even at rest and may suffer lung failure eventually.
Common symptoms include:
- Shortness of breath (dyspnea)
- Persistent cough with mucus
- Chest tightness
- Respiratory infections
Risk factors for COPD
In Singapore, COPD mainly affects people over the age of 40 and it is the sixth major cause of death. Its risk factors include:
- Cigarette smoking – the No.1 cause of COPD (80 to 90 per cent of those diagnosed are chronic smokers)
- Exposure to secondary smoke
- Exposure to chemical fumes, excessive dust and pollutants at work
- Recurrent respiratory infections
Treatment for COPDDoctors will usually prescribe medications which allow the airways to relax and open up (bronchodilators), inhaled corticosteroid medications, and antibiotics to treat COPD symptoms. Surgery and oxygen therapy can be considered for severe COPD. (Get more information on COPD treatment.)
Though lung damage caused by COPD is irreversible, medication can manage the symptoms and slow the progression of the disease.
“It’s important that slightly overweight COPD patients do not attempt to lose too much weight. In fact, they are better off carrying a little extra weight around than being underweight. Try to eat more protein to build muscle mass. And if you are a smoker, stop smoking completely,” Dr Ong advises.