Evaluating dyspnoea in chronic obstructive pulmonary disease

Abstract

Dyspnoea is the most common and troubling symptom in patients with chronic obstructive pulmonary disease (COPD) and the severity of the symptom engenders negative impacts on health status, exacerbation rate, healthcare resource utilization and prognosis. Therefore, alleviating dyspnoea is a primary treatment goal for most patients with stable COPD. The objective of improving dyspnoea is supreme in the management of COPD as few therapeutic interventions are disease-modifying in curtailing the underlying problem of accelerated loss of lung function leading to premature disability or death. However, in spite of the well-established fundamental mechanisms that induce dyspnoea in healthy individuals and patients with COPD, as well as the proven effectiveness of multiple and varied therapeutic interventions in reducing dyspnoea in such patients, the clinical evaluation and quantification of dyspnoea remain imprecise. Subjective measurement tools currently used in clinical practice are incapable of grading both immediate and longer-term changes in dyspnoea simultaneously, and repetitive scoring using questionnaires is burdensome for both the patient and observer. This paper reviews the current understanding and management of dyspnoea in COPD and discusses potential improvements in evaluating dyspnoea with the aim of achieving personalization of care for patients with COPD.

Clinical Evaluation of Dyspnoea in Obstructive Lung Disease – Progressing from Psychometrics to Physiology

“…The pathophysiological basis leading to the increased awareness of dyspnoea in patients with COPD have been well described elsewhere. 5,6,7 Increased perceived breathing effort is believed to reflect the awareness of increased motor command output to the respiratory muscles (respiratory neural drive) via the augmented central corollary discharge from the respiratory motor centres to the somatosensory cortex. 4 In other words, respiratory motor areas of the brain, can send an ascending copy of their descending motor activity to perceptual areas (corollary discharge), and the overall sensation of dyspnoea is processed in the higher somatosensory cortex.…”

“…11 In general, measurement tools for dyspnoea may be classified into three distinct sets: (1) short-term measures of intensity of dyspnoea, e.g., Borg scale and visual analog scale (VAS); (2) situational measures, e.g., the baseline dyspnoea index, the transition dyspnoea index (BDI-TDI) and the mMRC dyspnoea scale; (3) impact measures of dyspnoea on functional status or health status, e.g., the Chronic Respiratory Questionnaire. 7 Another way to "classify" measurement tools is by the domains of dyspnoea that they measure: sensory-perceptual experience (e.g., Borg and VAS scales), affective distress, symptom impact or burden (e.g., MRC and scales of health status). 3 Pros and cons of each class of dyspnoea measurement tool exist.…”