‘Rome Proposal’ Sets Framework for Classifying COPD Exacerbations
An international team of researchers has published a new framework, dubbed the Rome proposal, for defining and classifying exacerbations of chronic obstructive pulmonary disease (COPD).
“The ‘Rome Proposal’ represents an important milestone for better understanding and treating a very important and troubling component of COPD progression and, the prospect for more accurate treatment and better quality of life for people living with this condition,” Gabriele Nicolini, of the Chiesi Group, said in a press release. Nicolini is head of global medical affairs at Chiesi, a research-focused Italian pharmaceutical company, which sponsored the study.
“The updated definition and severity classification offer physicians a structured methodology and decision-making tool to detect and swiftly respond to ECOPD [COPD exacerbations],” Nicolini said.
The proposal was described in a paper, “An Updated Definition and Severity Classification of Chronic Obstructive Pulmonary Disease Exacerbations: The Rome Proposal,” published in the American Journal of Respiratory and Critical Care Medicine.
Exacerbations are generally defined as episodes in which COPD symptoms suddenly and markedly worsen. However, this loose definition has numerous limitations: it is highly subjective, as it relies on a patient’s assessment of symptoms, and provides no guidance about the timing of exacerbations.
Moreover, the severity of these episodes is usually graded after the fact, based on what medication(s) were used to control symptoms. This introduces a lot of variability and bias, since different hospitals, doctors, or patients — especially across continents and cultures — may have individual preferences or habits that influence treatment decisions.
Given these limitations, a group of experts from North America and Western Europe convened to create a more precise and reliable definition and classification of COPD exacerbations. The group had originally planned to meet in person in Rome, Italy — hence the title of the proposal — but moved to virtual meetings due to the COVID-19 pandemic.
The team shared experiences and conducted a thorough review of available scientific literature to define the features of COPD exacerbations, noting that shortness of breath, called dyspnea, and cough are very common, along with increases in sputum (thick mucus). An elevated heart rate, known as tachycardia, and/or rapid breathing, called tachypnea, also can occur.
“These observations helped with reaching a consensus that the upper time limit for an ECOPD to develop is 14 days from first onset of symptom worsening and that an ECOPD may develop over just hours in some cases,” the team wrote.
They added that exacerbations are characterized by acute bursts of inflammation in the airways, which often are triggered by infectious viruses or bacteria, or by irritants or pollutants.
Taken together, the team proposed that a COPD exacerbation should be defined as “an event characterized by dyspnea and/or cough and sputum that worsen over [less than or equal to] 14 days, which may be accompanied by tachypnea and/or tachycardia and is often associated with increased local and systemic inflammation caused by airway infection, pollution, or other insult to the airways.”
Exacerbations can be life-threatening, the team noted, and require proper evaluation and treatment.
“This revised definition addresses many of the shortcomings of the current definition and should better inform clinical care, research, and health service planning,” the researchers added, though they noted that the definition “needs to be validated prospectively in adequately designed and powered studies.”
The researchers noted that the Rome proposal was more than a year in the making.
“Credit must be given to the panel of international experts of multiple specialties who, over one year of intense work, were able to dissect the literature and, using a methodological approach, provide a final proposal that once validated in prospective studies, should help the field move forward,” said Bartolome R. Celli, MD, a professor at Harvard Medical School and co-author of the proposal.
To grade the severity of exacerbations, the scientists recommended measuring five variables: dyspnea, blood oxygen saturation, respiratory rate, heart rate, and levels of the inflammatory protein CRP (C-reactive protein) in the blood.
For each of these measures, specific severity criteria were noted. For example, dyspnea was considered “severe” if a patient rated it as a five or higher on a scale from zero to 10, in which zero indicates no shortness of breath and 10 corresponds to the worst of shortness of breath experienced. Experts also agreed that a CRP level of 10 mg/L or higher can be used to distinguish mild from moderate exacerbations.
“For an episode to be considered moderate, at least three of these five parameters, all of which carry a similar weight, should be worse than those threshold values characteristic of a mild ECOPD,” they wrote.
For an exacerbation to be considered severe, the panel determined that a sixth variable — indicating the presence of elevated levels of carbon dioxide in the blood and respiratory acidosis, a condition that causes body fluids to become acidic — should be taken into account.
The proposal also notes that some other health conditions commonly occur in COPD patients and may mimic symptoms of an exacerbation, requiring special attention to ensure appropriate diagnosis and treatment.
“The ‘Rome Proposal’ highlights the importance of making the right diagnosis and conducting a careful differential diagnosis of the several chronic diseases that are almost invariably associated with COPD in stable conditions, and that may worsen during exacerbations,” said Leonardo Fabbri, MD, a co-author from the University of Ferrara, in Italy.
“This includes not only heart failure, pneumonia and thromboembolism but also ischemic heart diseases, arrhythmias, asthma, bronchiectasis, pneumothorax and many others,” Fabbri said.
According to the researchers, the proposal sets forth a set of “well-established, measurable, and clinically relevant markers.”
“This will allow clinicians to establish ECOPD occurrences based on objective metrics, thus removing the uncertainties arising from patients’ subjective description of their symptoms and unconscious bias,” the company said.