LRTIs: Society’s Biggest Burden
The impact of LRTIs on all aspects of society
In 1915, the average life expectancy at birth for a man was less than 49 years and women could expect to live to 54. In a time when sewage was disposed of on the streets, it’s understandable that the most common cause of death was infection, in particular, lower respiratory tract infections (LRTIs). Fast forward to 2015 and a man’s life span was extended to 79.3 years and almost 83 years for a woman, with the most common causes of death relating to cancer, heart conditions and external causes.1 However, in 2016 LRTIs remained to be the deadliest communicable disease, causing 3 million deaths worldwide in 2016 alone and being the fourth biggest cause of death globally.2
Modern science has seen the development of antibiotics and successful vaccines that have eradicated many diseases entirely. With testing relatively simple in identifying infections and with treatments proven and available, why are LRTIs still so extremely prevalent? The statistics of LRTI mortality shine a spotlight on the true severity of how they burden our society.
What is an LRTI?
Lower respiratory tract infections (LRTIs) are any infection in the lungs, that occur below the larynx. Well known examples of LRTIs are pneumonia, bronchitis and tuberculosis and can be caused by both bacteria and viruses. Coughing is a symptom of less severe LRTIs with more severe infections causing difficulty with breathing and chest pains.3
Public health advice is simple for preventing the spread of LRTIs and suggests it can be as easy as washing your hands more, quitting smoking and sneezing into tissues.4 Other simple steps to prevent contraction of an LRTI include avoiding touching your face with unwashed hands, avoiding known irritants and cleaning and disinfecting surfaces regularly.3
In which patients do we need to act urgently?
Most healthy people make a full recovery from uncomplicated LRTIs. However, when complications occur, they can be serious. Those most at risk of developing complications are people with existing health conditions, adults over the age of 65 and children under 5 years old.3
The prevalence of LRTIs in respiratory disease patients in particular, is high. During a recent study, in a cohort of stable bronchiectasis patients, viruses were detected in 92% of patients during the winter season and 33% of patients during the summer season.5
Another example is COPD, a common cause of disability and estimated to become the third leading cause of death worldwide in 2030. LRTIs exacerbate COPD which form a large part of the disease burden. Over £250 million is spent on treating COPD exacerbations annually in the UK, including LRTIs. Recurrent exacerbations are associated with increased morbidity and mortality.6
Not only do LRTIs have a high mortality rate, they also have a substantial impact on quality of life. DALYs are a measure of years of ‘healthy’ life lost, caused by a disease. This can give an indication of the burden of a disease.7 DALYs lost to lower respiratory tract infections amount to 79 million (5.4%) worldwide and 2.2 million (1.5%) in the WHO European region.8 In 2016 the third highest accumulation of DALYs lost were to LRTIs.9
Let’s talk about NTM infections.
Non-tuberculous mycobacteria (NTM) infection have been strongly linked with bronchiectasis patients pathophysiologically, and prevalence of NTM in bronchiectasis patients is estimated to be 9.3%.10 11 However, in bronchiectasis patients, who are recommended to be tested for NTM by both British Thoracic Society (BTS) and European Respiratory Society (ERS) guidelines, only 17.2% of UK patients enrolled in the European Multicentre Bronchiectasis Audit and Research Collaboration (EMBARC) registry were actually tested for NTM at least once. The percentage of patients tested varied substantially between regions, ranging from 8.3% to 35.5%.12 Only by testing, will we establish the true prevalence of NTM in bronchiectasis patients. Increasing and standardising testing for NTM in the UK in bronchiectasis patients will give an accurate incidence and highlight the extent to which NTM is currently overlooked.
In a 2012 study investigating the role of NTM in COPD disease progression, 24.7% of COPD patients had been admitted for exacerbations at least once a year, and patients with multiple and single NTM isolates were more than twice as likely as those with no isolate to experience such exacerbations. This study suggests that NTM plays a role in disease progression and deterioration of pulmonary function in COPD patients.13 NTM is contributing to the cost of COPD exacerbations and the increase they cause in morbidity and mortality.
Where do we start with tackling the LRTI crisis?
With an increasing ageing population, the number of those most at risk of severe LRTIs is on the rise. It is a scary reality for these patients, even more so for those with existing lung diseases. Understanding the importance and impact of NTM for these patients will enable more patients at risk to be tested and treated which could ultimately help tackle the LRTI crisis. Act now, test for NTM.