The purposes of this study were: to examine the decriptors of breathlessness chosen by a large sample of patients with cardiorespiratory disease; to determine test-retest reliability of a patient's selection of the descriptors; and to assess whether a patient's recall of the experience of breathlessness is the same as that provoked by physical activity. Questionnaire data were collected at an initial visit for patients who complained of breathlessness and at a second visit in a subgroup of patients. A total of 218 patients who sought medical care for difficulty breathing due to one of seven different conditions were recruited from an outpatient pulmonary disease clinic at a university medical center. Patients selected statements that described qualities of breathlessness from a 15-item questionnaire and completed pulmonary function tests. At a subsequent visit (4 to 15 d later) a subgroup of 16 patients with chronic obstructive pulmonary disease (COPD) repeated the questionnaire at rest (to assess reliability) and after walking in a hallway to provoke a moderate intensity of breathlessness (to compare recall with direct experiences). The relationship among descriptors was evaluated by cluster analysis. The "work/effort" cluster was common for all diagnoses. Each condition was characterized by more than one cluster except COPD. Each diagnosis was associated with a unique set of dusters (e.g., asthma with "work/effort" and "tight," interstitial lung disease with "work/effort" and "rapid" breathing). Percent agreement for all descriptors selected at Visits 1 and 2 (recall) was 79% (r = 0.82; p = 0.001). Percent agreement at Visit 2 between descriptors for recall and for breathlessness provoked by walking was 68% (r = 0.69; p = 0.004). We conclude that patients with different cardiorespiratory conditions experience distinct qualities of breathlessness. Patients' recall of their sensations of breathlessness is reliable and comparable to dyspnea with walking. Employing a questionnaire containing descriptors of breathlessness may help to establish a specific diagnosis and to identify mechanisms whereby a specific intervention relieves dyspnea.

To investigate the hypothesis that clinical methods and psychophysical testing provide different information about breathlessness, we compared dyspnea ratings from a modified Medical Research Council (MRC) scale, the Oxygen-Cost Diagram (OCD), and the Baseline Dyspnea Index (BDI) with the perceived magnitude of added loads in 24 patients with obstructive airway disease (OAD) who experienced dyspnea on exertion. Age of the patients was 55.8 +/- 13.7 yr (mean +/- SD), FEV1 was 1.77 +/- 0.81 L, and FEV1/FVC ratio was 52.6 +/- 10.5%. Dyspnea ratings were obtained for each clinical method by 2 independent observers; estimates of the magnitude of 5 resistive loads (10 to 85 cm H2O/L/s) were obtained using the Borg category scale (0 to 10). For comparative purposes, 12 age-matched (48.9 +/- 13.5 yr) healthy subjects were also studied. Clinical ratings of dyspnea obtained in patients for MRC (range, 0 to 4), OCD (range, 23 to 98), and BDI (range, 0.5 to 12.0) were all highly interrelated (rs = 0.79, -0.83, and -0.71; p less than 0.001 for all comparisons). Exponents of the psychophysical power function for resistive breathing loads were similar for patients with OAD (0.57 +/- 0.27) and control subjects (0.63 +/- 0.18) (p = NS). Clinical dyspnea scores were significantly correlated with both FEV1 and FVC; however, neither dyspnea ratings nor lung function were significantly related to the exponent for added breathing loads in the patient group. These comparisons indicate that in patients with symptomatic OAD, clinical methods for rating dyspnea are interrelated and are correlated with lung function, but are independent of perception of resistive breathing loads.(ABSTRACT TRUNCATED AT 250 WORDS)

In this study we developed self-administered versions of modified baseline and transition dyspnea indexes and compared the scores obtained by this method with the mean value obtained by two trained interviewers. Twenty-five patients (14 males/11 females) with chronic obstructive disease who had a chief complaint of "breathlessness" were tested. Age was 66+/-11 years; forced expiratory volume in one second was 48+/-23% predicted. The baseline total scores were 5.0+/-1.8 for the interviewers and 5.4+/-2.0 for the self-administered method. For the baseline dyspnea scores the correlations were 0.83 (p<0.0001) between self-administration and the mean value of two interviewers and 0.75 (p<0.0001) between the two interviewers. The transition total scores, obtained an average of 102 days (range, 7-377 days) later, were - 0.1+/-3.0 for the interviewers and - 0.4+/-3.0 for the self-administered method. For the transition dyspnea scores the correlations were 0.94 (p<0.0001) between self-administration and the mean value of two interviewers and 0.83 (p<0.0001) between the two interviewers. The self-administered dyspnea scores had similar correlations with measures of lung function as did the interview dyspnea scores. We conclude that self-administered versions of the modified baseline and transition dyspnea indexes provide comparable scores as those obtained by trained and experienced interviewers. The advantages of the self-administered versions include standardized methodology and computerized scoring.

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The purpose of this study was to determine the predictor variables for breathlessness and to investigate the criteria of reliability and responsiveness for measuring breathlessness during progressive, incremental exercise on the cycle ergometer. We studied a heterogeneous group of patients with stable asthma (mean +/- SEM age, 46 +/- 4 yr) for four visits at weekly intervals. Predictor variables were determined at the first visit. Nine independent physiologic variables were obtained at each minute during exercise; the Borg rating of breathlessness (range 0 to 10) was used as the dependent variable. The regression model relating the physiologic parameters to the Borg rating of breathlessness was highly significant (model F = 43.4; p = 0.0001). Backward elimination selected the strongest predictors of the Borg rating: peak inspiratory flow (VI); tidal volume (VT)/FVC; frequency of respiration (f); and peak inspiratory mouth pressures (Pm). These four variables explained 63% of the variance in the rating of dyspnea. Each of the four variables exhibited a linear relationship with the Borg rating. Test-retest reliability was assessed by comparing results at the first and second visits. Individual slopes (except for VT/FVC) and intercepts for the four predictor variables versus Borg ratings were highly reliable. The slope for work intensity (watts) and Borg ratings, but not the intercept, was highly reliable. Responsiveness was evaluated by randomly administering inhaled methacholine or inhaled metaproterenol, alternately, at the third and fourth visits to induce acute changes in lung function before exercise.(ABSTRACT TRUNCATED AT 250 WORDS)