Reported dyspnea and fatigue using different scales during the physical effort in COPD

Abstract

Introduction: Therapy choice and its progression for patients with Chronic Obstructive Pulmonary Disease (COPD) should be based on their symptoms and clinical condition according to reports of dyspnea and fatigue. Therefore patient-reported scales have presented a key role during the communication with the patient. Objective: To verify if patients with COPD prefer the Modified Borg Scale (MBS), Visual Analogue Scale (VAS), Glasses Scale (GS), Faces Scale (FS) or Ratings of Perceived Exertion (RPE) during the six-minute walk test(6MWT), and to compare and correlate the scales with each other, with peripheral oxygen saturation (SpO2) and heart rate (HR). Methods: 28 patients with COPD (50% had mild to moderate COPD and 50% had severe to very severe) were evaluated by a respiratory and cognitive assessment. Additionally, they performed the 6MWT, in which the scales were applied simultaneously (random order) and patients reported their preference in the end of the test. Results: 57% of patients were illiterate or presented incomplete primary education and most of them (67%) chose the FS or GS. Significant positive correlations were observed between instruments for both dyspnea and fatigue in the end of the 6MWT, which the strongest was between MBS and  FS (r = 0.95). Nevertheless, there was no correlation between the scales and SpO2 and HR. Conclusion: As the majority of patients preferred pictured to numerical scales we suggest their use as a resource for therapeutic evaluation; MBS might be replace by FS, even though they have different scores and not scaled proportionally. However, this change must be carefully considered because there is the risk of dubious interpretation.