Air pollution is a risk factor for COPD and other respiratory disorders. According to a 2016 World Health Organization report, about 92% of the world’s population is exposed to dirty air. The Commission on Air pollution and Health, which is the most comprehensive global analysis to-date, and published in The Lancet in October 2017, suggests each year air pollution kills over 9m people prematurely, and costs US$4.6tn, which is equivalent to more than 6% of global GDP.
In advanced industrial economies exposure to tobacco smoke is the number one risk factor in developing COPD, where cigarette smoking is linked to 80% of all COPD deaths. In the US, for instance, approximately 25% of the adult population continue to smoke, despite aggressive smoking prevention and cessation efforts. Each year COPD claims some 134,700 American lives, and COPD is the 4th leading cause of death in the US, and expected to be the 3rd by 2020.
In developing economies COPD burden is caused more by exposure to indoor air pollution, such as the use of biomass fuels for cooking and heating. Almost 3bn people worldwide use biomass and coal as their main source of energy for cooking, heating, and other household needs. In these communities biomass fuels are often burned inefficiently in open fires, leading to high levels of indoor air pollution responsible for a greater degree of COPD risk than smoking or outdoor air pollution. Biomass fuels account for the high prevalence of COPD among non-smoking women in parts of the Middle East, Africa and Asia, where indoor air pollution is estimated to kill 2m women and children each year. COPD research and data from these regions are sparse.
In some people, COPD is caused by a genetic condition known as alpha-1 antitrypsin deficiency (AATD). People with AATD do not make a type of protein that helps to protect the lungs. Because not all individuals with COPD have AATD, and because some individuals with COPD have never smoked, it is suggested that there are other genetic predispositions to developing COPD. AATD is not a common cause of COPD, and few people know they have the genetic condition. In the US for example, it is estimated that only about 100,000 people have AATD.
Symptoms and diagnosis
The typical symptoms of COPD are cough, excess sputum production, and dyspnea (difficulty breathing), recurring respiratory infections, and fatigue. Because symptoms develop relatively slowly, sometimes people are unaware that they have lung problems. People with COPD are diagnosed by way of a multifactorial assessment that includes; spirometry, clinical presentation, symptomatology, and risk factors.
The heterogeneous nature of COPD, and the fact that it affects different people differently, and different therapies impact the condition differently, presents challenges for clinicians. There are several types of drugs, which can be used for the condition based on whether the drug is intended to improve airflow obstruction, provide symptom relief, modify or prevent exacerbations, (a worsening of symptoms often precipitated by infection), or alter the progression of the disease. It is possible that a drug may affect only one aspect of the condition or that it may act on many. It is also possible that a drug may benefit COPD patients in other meaningful ways.
View from a leading pulmonologist
“Some treatments for COPD overlap with asthma,” says Murali Mohan, Consultant Pulmonologist from Narayana Health City in Bangaluru, India. “The foundation for treating COPD is inhaled long-acting bronchodilators, whereas corticosteroids are beneficial primarily in patients who have coexisting features of asthma, such as eosinophilic inflammation and more reversibility of airway obstruction. . . . An important part of COPD management is for smokers to stop, and to reduce a patient’s exposure to pollutants both in the home and at work. Vaccines are used to prevent serious infections . . . . . . People with COPD tend to eat less, and become breathless when they eat. There is a lot of systemic inflammation, which causes patients to lose weight, but being overweight is just as bad. So we ensure that COPD patients adopt a healthy diet and exercise. This is to obtain an ideal body weight, and to supplement muscle strength, which is very important because it’s the muscles that move the lungs and gets the air in and out of the chest . . . . Often we recommend psychotherapy because a lot of people with COPD are depressed. More research is needed to better understand the conditions mechanisms, and to develop new treatments that reduce disease activity and progression,” says Mohan, see videos below.
What are the treatments for COPD?
COPD market and changing treatment landscape
Given the vast and escalating global prevalence of COPD, the market for therapies is also huge, global, and rapidly growing, and giant pharmaceutical companies aggressively compete for market share. The current size of the COPD market is estimated to be US$17bn. The overall respiratory therapeutics market, which in addition to COPD, includes, asthma, idiopathic pulmonary fibrosis (IPF), and cystic fibrosis, is about US$30bn and projected to grow to US$47bn by 2022. Currently, there are some 900 drugs in development for all types of respiratory disorders. The sheer size and rate of growth of this market, plus the fact that there is still no definitive treatment for COPD, motivates pharmaceutical companies to commit millions to its research. Notwithstanding, the overwhelming majority of current research data are derived from a relatively narrow band of developed nations.
Influence of cigarette smoking on COPD research
For many years COPD research concentrated on the condition’s association with cigarette smoking. This led to the early discovery that a subgroup of patients with emphysema was genetically deficient in an inhibitor of an enzyme that breaks down proteins and peptides. Although this explanation captures key elements of COPD, it has neither led to a reduction in its prevalence or morbidity, nor to the development of any therapy proven to modify the disease process itself, or to an adequate understanding of how risk factors other than cigarette smoking may contribute to COPD pathogenesis.
Although research has improved and our understanding of COPD has advanced, there remain challenges for researchers. Contributing to these is a broader array of mechanisms implicated in COPD’s pathogenesis compared to many other respiratory disorders. Notwithstanding, there has been a determined focus on a range of targeted biologic agents as potential therapies for the condition, which has led to an improved understanding of the pathophysiology and clinical manifestations of COPD; and the increased awareness of the importance of inflammation.
Although, innovative sampling techniques have led to the identification of several pulmonary biomarkers, (measurable substances that signal the presence of disease in the blood or tissues), which potentially could provide an enhanced insight into the pathophysiological mechanisms of exacerbation, sampling methods still could be improved because the utility of current methods is not yet established, and they have yet to provide compelling data in support of their use in COPD. This suggests a need for more research directed toward identifying the bases of COPD exacerbations, and clarifying the pathophysiological processes that contribute to worsening of symptoms. Other research studies focus on the underlying genetics of COPD in order to find better ways of identifying which smokers are more likely to develop COPD.
Challenge of COPD data
When recruiting patients for COPD studies, it is impossible to determine the speed at which the lung function will deteriorate in any given individual. This raises methodological challenges particularly with regard the size and nature of a cohort at the beginning and end of a study. Further, longitudinal studies require regular, and systematic collection of patient data, which may be a combination of self-reporting, electronic patient records (EPR), and results of tests undertaken by health professionals. Collecting longitudinal patients’ perceptions of the status of their COPD from a dispersed patient cohort is challenging because of different distributions of the disease, and the variation in the availability and quality of significant events, such as exacerbations.
More recently, apps have been developed to encourage the self-management of COPD, but they are also potentially helpful for research. This is because apps are able to unobtrusively enter the daily lives of people with COPD. However, the utility of apps as research aids is limited because rarely are they configured to aggregate, export and share the data they collect. However, this is changing.
The large and rapid growth of the health-related apps market, and the impact it has on shaping the attitudes and expectations of millions of people about healthcare, suggests that the utility of such devices to support clinical research will increase. Helpful in this regard is the fact that apps are being configured to enable rapid remote tests, and collect, transmit, store and analyse data.
Data validity and patient compliance
Notwithstanding, two significant challenges associated with apps remain for COPD researchers. One concerns the technological adequacy of apps to consistently produce valid data, and another is the compliance of patients in COPD studies. Both of these concerns however are being addressed.
A study, published in 2017 in the journal Nature Biotechnology, provides some validation for data derived from apps to be used in clinical studies. Scientists developed an app to collect survey data from 7,600 asthma sufferers over a 6-month period on how they managed their condition. Researchers then compared these app-generated patient-reported data with similar data from traditional asthma studies and found that there were no significant differences. Although there still remains some methodological challenges associated with using apps to recruit patients for clinical studies, findings from this and other studies give scientists some degree of confidence that app-derived data can be reliable enough for clinical studies.
Giant tech companies and medical research
The increasing validation of app-generated health data is driving the growth in pairing wireless health apps with data monitoring, and creating an opportunity for giant global technology companies to enter the healthcare market by joint venturing with big pharmaceutical companies. Such ventures create big-data opportunities to aggregate vast amounts of patient data from millions of COPD sufferers and the efficacy of specific drugs. Such ventures also allow patients remotely to keep track of their drug usage, and for health professionals to instantly access the data to monitor an individual patient’s condition.
There is some evidence to suggest that people with COPD are less compliant recording information about their condition when they are experiencing an exacerbation, or just not feeling well. A solution might be to employ techniques, which “nudges” patients to be more compliant. The genesis of nudge systems is a 2008 publication, Nudge, by US academics Cass Sunstein and Richard Thaler. The authors suggest that making small changes to the way options are presented to individuals “nudges” them to engage in behaviours that they would not normally do. Following the publication of the book, “nudge units” were set up in the White House and in 10 Downing Street to encourage people to change entrenched behaviours in order to improve occasional and unsystematic public services, while reducing costs.
The UK’s Nudge Unit has, among other things, significantly increased the rate of organ donation, and encouraged a substantial number of individuals to initiate and maintain healthier lifestyles. Minded of the successes, governments throughout the world have set up nudge units. A 2017 OEDC report suggests that nudge units have entered the mainstream, and could be used much more widely. Also in 2017, Richard Thaler was awarded the Nobel Prize for his contribution to behavioural economics. COPD researchers might consider replacing the current “pull” techniques with nudge techniques to enhance patient compliance in COPD clinical studies.
For years COPD research was in the doldrums, but over the past decade things have changed significantly. Notwithstanding, COPD studies could benefit from more compelling data, and this could be achieved by employing smart online communications strategies that increase the connectivity of globally dispersed COPD researchers and individuals living with the condition with an eye to enhance patient compliance in COPD studies, increase the quality of research data, and expand the geographies from which COPD data are retrieved.