Chronic obstructive pulmonary disease (COPD), refers to a group of progressive lung conditions marked by narrowing of the airways and difficulty emptying air out of the lungs. The two main conditions include emphysema and chronic bronchitis, which often coexist.

OVERVIEW OF COPD
• COPD is one of the most common respiratory conditions. As per the Global Burden of Disease Study, over 250 million cases were reported worldwide in 2016.

• More than 3 million deaths due to COPD were reported in 2015 (approximately 5% of global deaths during the year). Nearly 90% of COPD deaths occur in low and middle income countries.

• The disease usually begins around the mid –thirties particularly in smokers but often diagnosed only in the fifties.

• Earlier, the disease was more common in men due to smoking, but with increasing women smokers in the developed countries and exposure to indoor pollution due to use of biomass fuel for cooking by women in low income countries, the condition now affects both sexes almost equally

• In emphysema the air spaces or alveoli, the terminal portion of the airways become destroyed and trap air. The alveoli collapse due to loss of elasticity and damage to intervening lung tissue both of which normally exert a pull on them to keep them from collapsing

• Chronic bronchitis, on the other hand is characterized by inflammation and narrowing of the airways with production of excess mucus or phlegm

• In both these conditions, the outward flow of air is disrupted and as a result, the person is unable to take in fresh oxygen or get rid of the excess carbondioxide that accumulates within the body

• Both these conditions are progressive and cannot be reversed but treatment can reduce the severity of symptoms and thus it is essential to get an early diagnosis

CAUSES OF COPD
• COPD is caused by breathing in harmful substances that damage the lung tissue, chiefly cigarette smoke. Equally exposure to second hand smoke is also associated with an increased risk of developing COPD. Children especially are vulnerable and it is important to avoid smoking where children are around

• Longterm exposure to harmful chemicals due to air pollution, and dust can cause COPD.

• The risk of COPD is higher in persons with asthma and smokers

• Occupational exposure to cotton dust, coal dust, silica, and grain dust has been reported to cause COPD. The resultant condition is referred to as occupational lung disease. Other substances implicated include animal dander, natural rubber latex, platinum salts, isocyanates and several agents, all of which can cause or aggravate asthma

• Indoor pollution due to breathing in fumes from biofuel used for cooking and heating and tobacco

smoke, especially in poorly ventilated homes can cause COPD

• Persons with alpha-1 antitrypsin deficiency have a genetic predisposition for developing COPD. This condition damages lung tissue and liver tissue.

SYMPTOMS OF COPD
In the early stages, symptoms may be mild and intermittent but as the disease progresses, the symptoms become more severe and persistent.

Early symptoms include
• Mild but recurrent cough
• Early morning cough and needing to clear the throat on waking
• Occasional breathlessness, especially on exertion

With progression of disease, symptoms are more severe, including
• Breathlessness on minimal exertion
• Chronic persistent cough with/without phlegm
• Fatigue and lack of energy
• Chest tightness and difficulty in breathing
• Wheezing (high pitched noisy breathing on inhalation)
• Recurrent respiratory infections

In the advanced stages,
• Extreme tiredness
• Breathlessness at rest
• Weight loss
• Swelling of feet and ankles

Immediate medical attention is required if the lips and finger nails turn blue (indicating low oxygen saturation in the blood), heart rate is increased, severe breathlessness and inability to speak, and feeling faint or confused

DIAGNOSIS OF COPD
• Detailed history – The doctor will take a detailed history including history of smoking, exposure to second hand smoke, exposure to chemicals and fumes due to air pollution, occupational exposure, family history of COPD, drug history and history of asthma

• Physical examination – Thorough general examination including BMI measurement and chest examination with a stethoscope (auscultation) will be performed to assess the state of lungs

• Degree of lung damage and lung function can be evaluated by a simple test called spirometry. During this test, the patient blows out hard into a machine following a deep breath. This measures lung capacity and how quickly the patient can empty your lungs. It is also called forced expiratory volume in one second, often shortened to FEV1.

• Arterial blood gas analysis to measure oxygen and carbon dioxide saturations

• Imaging investigations such as chest x-ray and CT scan which will give detailed information about changes in the lungs and heart

The above investigations can help to confirm the diagnosis of COPD or detect the presence of other conditions such as asthma, heart failure or restrictive lung disease

TREATMENT OF COPD
Early diagnosis and treatment can provide relief of symptoms and prevent acute flare-ups. Treatment measures include the following

Medications
• Medical treatment depends on the severity of symptoms.
• Bronchodilators are prescribed either as inhalers or as nebulizers to widen the narrowed airways and make breathing easier.
• A steroid agent may be added to reduce inflammation of the airways and especially if there is a background of asthma.
• If there is chronic cough with thick sputum production a mucolytic or mucus thinning agent may be advised. This makes it easier to cough out the sputum

Oxygen therapy
• If the oxygen saturation of the blood is low, administered via a nasal canula or oxygen mask. A portable unit will make it easy for the person to move around while on oxygen therapy

Surgery
• Surgery is indicated only when other measures have failed, particularly in severe emphysema. Types of surgery include bullectomy (removal of abnormal air spaces in the lung), lung volume reduction surgery and rarely lung transplantation

Lifestyle changes
• Last but not least, cessation of smoking is essential to prevent further lung damage.
• Avoid exposure to fumes and second hand smoke
• Prevent/control occupational exposures
• Consume a healthy diet rich in fresh fruits and vegetables
• Exercise as appropriate
• Lung rehabilitation program to improve lung function and decrease breathlessness