Gender and respiratory factors associated with dyspnea in chronic obstructive pulmonary disease

JP De Torres, C Casanova, A Montejo de Garcini… - Respiratory …, 2007 - Springer
JP De Torres, C Casanova, A Montejo de Garcini, A Aguirre-Jaime, BR Celli
Respiratory research, 2007Springer
Rationale We had shown that COPD women expressed more dyspnea than men for the
same degree of airway obstruction. Objectives Evaluate gender differences in respiratory
factors associated with dyspnea in COPD patients. Methods In a FEV 1% matched
population of 100 men and women with COPD we measured: age, MMRC, FEV 1, FVC,
TLC, IC/TLC, PaO 2, PaCO 2, D LCO, P imax, P 0.1, Ti/Ttot, BMI, ffmi, 6MWD and VAS scale
before and after the test, the Charlson score and the SGRQ. We estimated the association …
Rationale
We had shown that COPD women expressed more dyspnea than men for the same degree of airway obstruction.
Objectives
Evaluate gender differences in respiratory factors associated with dyspnea in COPD patients.
Methods
In a FEV1 % matched population of 100 men and women with COPD we measured: age, MMRC, FEV1, FVC, TLC, IC/TLC, PaO2, PaCO2, DLCO, Pimax, P0.1, Ti/Ttot, BMI, ffmi, 6MWD and VAS scale before and after the test, the Charlson score and the SGRQ. We estimated the association between these parameters and MMRC scores. Multivariate analysis determined the independent strength of those associations.
Results
MMRC correlated with: BMI (men:-0.29, p = 0.04; women:-0.28, p = 0.05), ffmi (men:-0.39, p = 0.01), FEV1 % (men:-0.64, p < 0.001; women:-0.29, p = 0.04), FVC % (men:-0.45, p = 0.001; women:-0.33, p = 0.02), IC/TLC (men:-0.52, p < 0.001; women: -0.27, p = 0.05), PaO2 (men:-0.59, p < 0.001), PaCO2 (men:0.27, p = 0.05), DLCO (men:-0.54, p < 0.001), P0.1/Pimax (men:0.46, p = 0.002; women:0.47, p = 0.005), dyspnea measured with the Visual Analog Scale before (men:0.37, p = 0.04; women:0.52, p = 0.004) and after 6MWD (men:0.52, p = 0.002; women:0.48, p = 0.004) and SGRQ total (men:0.50, p < 0.001; women:0.59, p < 0.001). Regression analysis showed that P0.1/Pimax in women (r2 = 0.30) and BMI, DLCO, PaO2 and P0.1/Pimax in men (r2 = 0.81) were the strongest predictors of MMRC scores.
Conclusion
In mild to severe COPD patients attending a pulmonary clinic, P0.1/Pimax was the unique predictor of MMRC scores only in women. Respiratory factors explain most of the variations of MMRC scores in men but not in women. Factors other than the respiratory ones should be included in the evaluation of dyspnea in women with COPD.
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