COPD characteristically starts in middle or past middle age and progresses slowly. A patient who has developed the disease at about 50 years of age, therefore, is likely to have a well established and advanced disease by the time he reaches 65 years or over. He is severely disabled because of breathlessness and suffers from frequent exacerbations due to recurrent infections and other complications.
COPD encompassing chronic bronchitis and emphysema, occurs most often in chronic and heavy smokers. Old age by itself does not cause COPD although the structural and functional alterations which take place with age, do contribute to lung function impairment, disease morbidity and mortality. Senile emphysema, a term which connotes age related emphysema is more a misnomer, than a disease. It only implies the presence of hyperinflated lungs due to increased elasticity. There is no true alveolar destruction unless the individual resorts to smoking which is likely to initiate true emphysematous changes and accelerate lung function decline.
Dyspnoea is a common symptom in the elderly even in the absence of COPD. This, in part is a general symptom and in part, related to increased cardio-respiratory demands. With aging, there is progressive worsening of cardiac disorders contributing to dyspnoea. It is worse if there is associated obesity, which is not uncommon in old age. Obesity causes increased work of breathing and respiratory muscle weakness.
Diagnosis of COPD is relatively simple. Clinical features and chest roentgengraphy, further aided by spirometric measurements are fairly diagnostic. Electrocardiography, echocardiography and sometimes exercise testing are required for cardiopulmonary assessment. Blood gas measurements are required to diagnose the presence and severity of respiratory insufficiency.
COPD is managed with general advice of stopping smoking, bronchodilators, expectorants and treatment of infections. For long term rehabilitation programmes, inspiratory muscle training and general exercise reconditioning are very useful. Domicilliary, long term oxygen therapy has been shown to benefit most such patients.
Acute exacerbations and respiratory failure are managed more actively with antibiotics, increased oxygen administration and other supportive therapy. Endotracheal intubation and a short period of assisted ventilation may be required in a severely hypoxic and hypercapnic patient.
It is better to manage these patients conservatively rather than aiming to achieve normal blood gas values. Mechanical ventilation, even if required, should be weaned off as early as possible. When prolonged, there develops respiratory muscle weakness and dependence on assisted ventilation. Unfortunately, we do not have a back up system of domicilliary care to provide home ventilation and other supports. Invariably therefore, a prolonged period of assisted ventilation becomes a source of an unending agony and misery to the patient and the family. It also burdens severely the already strained public health services in most instances.
Chronic airways obstruction in old age is more often caused by COPD but can occasionally be attributed to asthma which is either present from younger age or rarely starts de novo at old age. Asthma in the elderly needs to be differentiated from other causes of wheezing of which COPD is the most important. Left heart failure, pulmonary thromboembolism and central airway obstruction due to lung tumours are some other important causes. Eosinophilic syndromes, bronchial carcinoids or foreign body aspiration may also simulate a clinical picture of asthma.
Early recognition of asthma is important for efficient management. Asthma in the elderly is relatively poorly tolerated and requires more aggressive management requiring hospitalization earlier than late. An acute episode can prove to be fatal unless managed in time.
Bronchial hygiene is of particular interest in the elderly especially in the presence of airways obstruction. In view of the impaired defence mechanism, poor reflexes and weak respiratory muscles, an elderly patient is unable to cough and expectorate effectively. Bronchial secretions, being viscid and thick, may block respiratory passages and rapidly cause pneumonia and respiratory failure. Nebulization of bronchodilators and mucolytic agents and maintenance of hydration are important in liquefying the secretions. Parenteral corticosteroids and antibiotics are also required for acute exacerbations.
Respiratory physiotherapy is important to maintain bronchial patency. Expulsive coughing and other chest physical therapy (CPT) procedures such as chest percussion and vibration are helpful.
Both primary and metastatic lung tumours are common. Metastases may arise from cancers of breast, gastrointestinal tract, kidneys and urinary bladder, prostate and genital tract.
Primary Lung cancer occurs more commonly in the 6th and 7th decades of life. The mean age of lung cancer in India is reported to be lower (54-56 years) than in the West where it is above 65 years, in both males and females. There is evidence to suggest that the mean age of lung cancer is rising. In fact, the contemporary age incidence in India is similar to what was reported in the West some 40 years ago.
There are some differences in the histological types of cancer amongst smokers and nonsmokers in patients above 40 years of age. Squamous cell is most common amongst smoker and adenocarcinoma amongst the nonsmokers.
Diagnosis of cancer poses special problems. Invasive investigations are often required for which the patient is generally hesitant. Management plans involving both surgical and nonsurgical treatments are also cumbersome and generally tiring for a old person. Both radio and chemotherapy are poorly tolerated. Above all, the results are not curative in most instances. It is therefore palliative treatment which is often resorted to.