Diagnosis in chronic obstructive pulmonary disease—“Too little,too late?”

Introduction

The Global Burden of Disease study highlighted chronic obstructive pulmonary disease (COPD) and lung cancer and lower respiratory tract infection (LRTI) in the top 10 causes of mortality. ¹ Together, respiratory diseases account for 1 in 6 deaths, 1 in 10 disability adjusted life years lost (DALYs), and 7% of hospital admissions. ² Globally, COPD was ranked the fourth leading cause of death in 1990 and third in 2010. It was one of the few conditions that did not significantly decrease, falling only from 3.1 to 2.9 million ¹ . The annual worldwide cost of COPD is estimated at €48.4 billion. In the United Kingdom, 835,000 people have a diagnosis of COPD, with a further estimated 2.2 million people have not yet had the diagnosis confirmed. ³

COPD is challenging because it is a progressive, destructive disease with no clear pathological or clinical starting point. ⁴ The onset and progression is insidious leading to permanent damage before diagnosis. COPD has a significant progressive impact on the quality of life and activities of daily living for both individuals and their families. ⁵ Mortality from COPD can to some extent be modified by amenable factors that stretch across the care continuum, from primary prevention and early detection, structured and coordinated care management, and the delivery of health services. ⁶

Could COPD be diagnosed earlier?

A study of 40,000 patients in the United Kingdom illustrated missed diagnostic opportunities in 85% of patients in the 5 years before eventual COPD diagnosis. ⁴ In 8% of cases, the diagnosis could have been made 15–20 years earlier. ⁴ A Swedish study also illustrated that during the 20 years leading up to diagnosis the proportion and frequency of consultations increased suggesting missed opportunities. ⁷

Fundamentally, respiratory diseases in general suffer from delayed diagnosis. ³ There is considerable potential to include asthma, lung cancer, and even infective processes in this category due to the similarities between symptoms and the opportunity for more consistent diagnostic methods. For example, a largely artificial distinction is seen between early lung cancer diagnosis and other conditions. A holistic and more urgent approach to detection and diagnosis of respiratory symptoms will improve patient outcomes across the board. ⁸

Why is COPD poorly diagnosed?

COPD is underdiagnosed due to a failure of both health professionals and patients to recognize the early signs and symptoms of the disease. ⁹ Spirometry is still not routinely available in all general practioner (GP) practices, limiting diagnostic access. ⁴ In the Swedish study, 22% of patients were receiving a short- or long-acting anticholinergic bronchodilator without diagnosis of COPD being recorded. ⁷

Is it worth diagnosing earlier?

Identifying individuals with undiagnosed COPD will facilitate earlier interventions and reduce the health burden and financial cost of symptomatic COPD. ¹⁰ Early diagnosis and appropriate management has the potential to save the National Health Service (NHS) in England more than £1 billion over 10 years. ¹¹ Forced expiratory volume in one second (FEV₁) is a strong marker of premature death from cardiovascular disease, coronary artery disease, and stroke highlighting additional diagnostic benefits. ¹² Previous arguments which suggest that there is no point in diagnosing COPD until it becomes symptomatic are no longer tenable.

How could you do it?

Screening asymptomatic patients for COPD with spirometry is probably not justified. ⁷ The majority of evidence points towards the need for community-based spirometry to case find patients with early disease. The National Outcomes Strategy for COPD provides a framework for improving outcomes in England. ³ This suggests case finding should focus on patients with lower respiratory tract symptoms and concordant long-term comorbidities. ³ These patients could be picked up in the community upon presentation, through retrospective case finding or via case-finding software such as the GRASP COPD tool. ¹³

1. Patients presenting with lower respiratory tract symptoms

COPD should be considered and spirometry performed for patients over 40 years old and current or ex-smokers presenting who present with lower respiratory tract symptoms in primary care or those referred for chest radiography. ¹⁴ GPs should take responsibility and ownership for diagnosis of COPD and use prospective diagnostic reasoning to predict the disease trajectory.

• 2. Screening Health Checks

In England, the NHS Health Check is offered to all who are aged 40–74-years with the aim of detecting and managing risk factors to mainly focus on cardiovascular disease prevention. ¹⁵ Smoking status is assessed, but there is no assessment of respiratory function. Spirometry could be used for the assessment of respiratory disease and cardiovascular risk. ^16,17

• 3. Chronic disease management

Patients with COPD have a higher incidence of comorbidities due to shared risk factors. ⁴ These factors promote a cycle of debility, muscle wasting, increased susceptibility to exacerbations, and worsening comorbidities. ¹⁴ A holistic disease management approach considering all comorbidities will evaluate those at risk of developing COPD. Health-care strategy and initiatives from government are usually disease specific rather than cross boundaries. ¹⁸

• 4. Community pharmacists

People attending community pharmacists for repeat prescriptions for inhalers, steroids, antibiotics, and cough medicines could be a point for targeting interventions. ⁴ Pharmacists could perform the spirometry, manage result interpretation, educate regarding inhaler technique, and provide red flag advice.

• 5. Public awareness

COPD management comprises a number of different approaches including smoking cessation, rehabilitation, immunization, education, and pharmacological treatment. Public health campaigns around breathlessness emphasize the importance and benefit of early diagnosis. ¹⁹ There is need to clarify tobacco legislation and tax on tobacco. The public smoking ban has made a contribution towards reducing individual and passive smoking and is expected to subsequently impact the development of respiratory disease in the future. ²⁰

Conclusion

COPD is a significant cause of global morbidity and mortality and along with other respiratory conditions is often diagnosed late and informally. There is no quick fix, but earlier diagnosis allows effective evidence-based interventions to modify respiratory and cardiovascular risk. This impacts the frequency of exacerbations and rate of progression of disease. Excessive mortality from respiratory conditions will not be reduced by better treatment unless diagnostic accuracy and timing is improved.