India ranks amongst the top countries in terms of deaths caused by various lung diseases.The most famous and reported cases of deaths due to respiratory illnesses that are often reported to larger public (through newspapers and media etc.) are often infectious in nature, mostly due to tuberculosis and pneumonia. However, we are only beginning to unravel the impact of non-infectious, long-term lung diseases in India.
These include asthma and chronic obstructive pulmonary disease (more commonly known as [chronic] ‘bronchitis’ and ‘emphysema’). Both Asthma and COPD are preventable, and treatments are available to at least control the daily symptoms of the disease. However, the prevalence of both these diseases is rapidly increasing around the world, and more so in developing countries such as India. In 2015, a large-scale study published in a well-known medical journal, The Lancet Respiratory Medicine, reported that approximately 32 lakh individuals died due to COPD, while 4 lakh people succumbed to asthma globally. In India, the estimated number of patients suffering from either asthma and COPD may be well over 100 million. In the last 25 years, the developed countries have invested and established substantial resources in understanding the mechanisms of these diseases and hence, limiting the disease burden due to these preventable diseases. On the contrary, India is left far behind in terms of prevention, awareness or management of these life-threatening respiratory conditions.
Asthma (also known as ‘Dama’) affects both children and adults in equal proportions. The disease itself could subside and re-emerge at any stage depending upon exposure to risk factors, such as pollutants, allergens etc. Asthma affects around 25% of Indian population, andaccording to the World Health Organization, the estimated number of asthmatics in India is approximately 15-20 million. However, other researchers speculate that the number of asthmatics in India may be as high as 30 million. Of note, the prevalence of asthma in Indian children (5-7 years of age) is around 10-15%, highlighting the fact that asthma onset is often during the early years of life. The age of 7 years seems to be crucial in confirming the establishment of asthma. The primary risk factor for asthma development are exposure to allergens, both external (air pollution, chemical irritants, dusts, weather changes and/or cigarette smoke) and internal (small insects such as cockroaches and domestic mites in the bedding, carpets, mold, pets etc.). In a developing country like India, where construction and urbanization are accelerating at a daily basis, the risk and prevalence of asthma is expected to rise substantially in coming decades. Moreover, a family member suffering from asthma is also a strong predictor of development and severity of asthma. Medically, asthma is characterized by frequent and recurrent episodes of breathlessness, tightness of chest (due to swelling and contraction of airways) and wheezing, all of which vary greatly in severity and frequency from one individual to another. The difficulty in breathing and obstruction in the airflow is generally treated with bronchodilators. If left untreated, asthma can result in hospitalizations and even death. Unfortunately, asthma cannot be cured as of now, however, robust asthma management strategies are available for controlling the disease.
The lack of awareness about COPD in India is widespread even among the educated masses. Although the Government and healthcare workers have been largely successful in highlighting the risks associated with tobacco use (including smoking, the primary risk factor for COPD), the campaign predominantly focusses on oral and lung cancers and ignores the risks of an important disabling diseases, COPD. This is evident from the fact that the true prevalence of COPD in India is largely unknown. COPD is broadly classified as chronic bronchitis or emphysema, which develops over a long period of continuous exposure to cigarette smoke, chemicals and fumes, or other irritants. The lungs respond to these external factors by mounting an inflammatory reaction, that is visible in terms of an increase of sputum production, frequent coughing and breathlessness that becomes more severe with ageing and disease progression. The diagnosis of COPD is based on the results of relatively simple and non-invasive breathing tests, that detects obstructions in the exhaled breath. This is achieved by a device called spirometer. Unfortunately, the unavailability of large-scale screening of ‘individuals at risk’ compliant with international standards, such as those mentioned and recommended by Global Burden of Obstructive Lung Diseases (GOLD), results (at best) in a speculative burden of COPD in India. Despite the limitation, several researchers predict the COPD prevalence in India ranges somewhere from 4% to 20%. A recent survey involving more than 1200 participants estimates the prevalence of COPD to be around 10%, which is at par with the disease burden in most countries around the world, including Australia, USA and UK.
COPD affects relatively elderly individuals (>40 years). The major risk factor for COPD remains cigarette smoking. Around 30% of Indian adults smoke daily. The majority of smokers are males, as smoking among females still remains a taboo in Indian society, at least in rural establishments where majority of population resides. However, COPD could also be caused due to chronic exposures to smoke from burning biomass sources (wood, cattle dung cakes etc.) for cooking/heating etc. Therefore, both females and young children are often exposed to this significant risk factor. Another major risk factor for COPD is air pollution, which is aplenty in India. Notably, as many as 13 out of 20 most polluted cities in the World are our very own cities! Last but not the least, there is still minimal awareness regarding the occupational exposures to hazardous chemicals, dusts and fumes in India, which has been frequently implicated in COPD. A small proportion of individuals (~5%) also exhibit genetic susceptibility towards COPD. The presence of all these risk factors in India, as well as lack of awareness regarding COPD prompts urgent attention from all the stakeholders in our society and we can all contribute in tackling this major global and national challenge before it’s too late to manage or control.
Many individuals demonstrate characteristics of both asthma and COPD, which is medically knwon as Asthma COPD overlap (ACO). Around 25% of total COPD/Asthma patients could very well be suffering from ACO. Moreover, compared to COPD or asthma alone,ACO patients have more rapid disease progression and exhibit more severe symptoms. These patients are often excluded from large clinical trials as they do not comply with the inclusion/exclusion criteria of particular studies, hence the detailed characteristics of ACO patients is not yet completely understood.
Collectively, these two major non-communicable lung diseases affect a vast population if we consider the absolute numbers. The course of both COPD and asthma is complicated by frequent bacterial and/or viral infections, that considerably increases the risk of hospitalizations and deaths. Treatment for both COPD and asthma primarily focus on reducing the hallmark symptoms of these diseases and improve the ‘breathability’ of the patient. Major treatment regimens include a bronchodilator (to open up the airways), corticosteroids (anti-inflammatory drugs) and antibiotics (to prevent/treat bacterial infections). Patients have to take these medications regularly to reduce the symptoms and manage the disease. Moreover, individuals with asthma and/or COPD are strongly advised to undertake preventive vaccination for influenza and pneumonia infections to develop immunity against common viral and bacterial infections. Although medical research is being undertaken around the world to find an appropriate therapy that could completely treat and/or cure these diseases, the breakthrough could be years away! This is due to the fact that both COPD and asthma are really complex and heterogeneous conditions and a common standard therapy may not necessarily benefit two individuals alike. In addition to the huge prevalence of these diseases, the economic costs associated with asthma and COPD are startling. For instance, the economic burden associated with asthma are projected to exceed the combined costs of managing tuberculosis and HIV/AIDS (two most deadly infectious diseases in India). The total sale of asthma medications has been reported to increase significantly (43%)from 2012 to 2016, indicating a substantial rise in asthmatics in India. According to estimates in 2011, the annual treatment cost of COPD is 350 billion rupees, which is expected to rise to the tune of 480 billion in 2016.
Despite the burden of asthma and COPD in India, the level of general awareness about these preventable diseases is still not widespread. In the meantime, all we need to do is to inform the stakeholders about the risks and early signs of these diseases, as well as most suitable prevention strategies. Albeit slowly, tobacco control policies are moving in the right direction. Moreover, the awareness regarding intake of daily recommended nutrition (i.e., balanced diet) is slowly gaining more attention in India. Furthermore, individuals working in the high-risk occupations (construction, chemical factories, mines, agriculture etc.) have to be made aware of the risks and preventive strategies along with the importance of personal protective equipment (masks, air purifiers etc.) to reduce the incidence of these chronic lung diseases. The socio-economic status, commonly measured by education, occupation, and/or income has a profound impact on health and longevity. It is also an important predictor of health and the outcomes of chronic diseases, including COPD and asthma, as the financial well-being of an individual determines the access to appropriately equipped healthcare facilities and the availability of medical counselling services. Last but not the least, everyone, including the medical practitioners, public health and policy makers, and most importantly, the general public have crucial roles to play in tackling the spread of these diseases.