BACKGROUNDThe current theory of dyspnea perception presumes a multidimensional conception of dyspnea. However, its validity in patients with cardiopulmonary dyspnea has not been investigated.

METHODSA respiratory symptom checklist incorporating spontaneously reported descriptors of sensory experiences of breathing discomfort, affective aspects, and behavioral items was administered to 396 patients with asthma, chronic obstructive pulmonary disease (COPD), diffuse parenchymal lung disease, pulmonary vascular disease, chronic heart failure, and medically unexplained dyspnea. Symptom factors measuring different qualitative components of dyspnea were derived by a principal component analysis. The separation of patient groups was achieved by a variance analysis on symptom factors.

RESULTSSeven factors appeared to measure three dimensions of dyspnea: sensory (difficulty breathing and phase of respiration, depth and frequency of breathing, urge to breathe, wheeze), affective (chest tightness, anxiety), and behavioral (refraining from physical activity) dimensions. Difficulty breathing and phase of respiration occurred more often in COPD, followed by asthma (R(2) = 0.12). Urge to breathe was unique for patients with medically unexplained dyspnea (R(2) = 0.12). Wheeze occurred most frequently in asthma, followed by COPD and heart failure (R(2) = 0.17). Chest tightness was specifically linked to medically unexplained dyspnea and asthma (R(2) = 0.04). Anxiety characterized medically unexplained dyspnea (R(2) = 0.08). Refraining from physical activity appeared more often in heart failure, pulmonary vascular disease, and COPD (R(2) = 0.15).

CONCLUSIONSThree dimensions with seven qualitative components of dyspnea appeared in cardiopulmonary disease and the components under each dimension allowed separation of different patient groups. These findings may serve as a validation on the multiple dimensions of cardiopulmonary dyspnea.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Asthma ; physiopathology ; Dyspnea ; classification ; diagnosis ; etiology ; Female ; Heart Failure ; physiopathology ; Humans ; Lung Diseases ; physiopathology ; Male ; Middle Aged ; Pulmonary Disease, Chronic Obstructive ; physiopathology ; Young Adult

BACKGROUND/AIMS: In assigning patients with chronic obstructive pulmonary disease (COPD) to subgroups according to the updated guidelines of the Global Initiative for Chronic Obstructive Lung Disease, discrepancies have been noted between the COPD assessment test (CAT) criteria and modified Medical Research Council (mMRC) criteria. We investigated the determinants of symptom and risk groups and sought to identify a better CAT criterion. METHODS: This retrospective study included COPD patients seen between June 20, 2012, and December 5, 2012. The CAT score that can accurately predict an mMRC grade > or = 2 versus < 2 was evaluated by comparing the area under the receiver operating curve (AUROC) and by classification and regression tree (CART) analysis. RESULTS: Among 428 COPD patients, the percentages of patients classif ied into subgroups A, B, C, and D were 24.5%, 47.2%, 4.2%, and 24.1% based on CAT criteria and 49.3%, 22.4%, 8.9%, and 19.4% based on mMRC criteria, respectively. More than 90% of the patients who met the mMRC criteria for the 'more symptoms group' also met the CAT criteria. AUROC and CART analyses suggested that a CAT score > or = 15 predicted an mMRC grade > or = 2 more accurately than the current CAT score criterion. During follow-up, patients with CAT scores of 10 to 14 did not have a different risk of exacerbation versus those with CAT scores < 10, but they did have a lower exacerbation risk compared to those with CAT scores of 15 to 19. CONCLUSIONS: A CAT score > or = 15 is a better indicator for the 'more symptoms group' in the management of COPD patients.
Aged ; Algorithms ; Area Under Curve ; *Decision Support Techniques ; Decision Trees ; Female ; Humans ; Lung/*physiopathology ; Male ; Middle Aged ; Predictive Value of Tests ; Pulmonary Disease, Chronic Obstructive/classification/*diagnosis/physiopathology ; ROC Curve ; Regression Analysis ; Reproducibility of Results ; Republic of Korea ; Retrospective Studies ; Risk Factors ; Severity of Illness Index