Clinical importance of sex differences in dyspnea and its sex related determinants in asthma and COPD patients.

PURPOSE

There is an increasing amount of data regarding the influence of sex on dyspnea perception, however, the influence of sex has not been included in clinical guidelines for asthma and chronic obstructive pulmonary disease (COPD).

MATERIALS AND METHODS

The study included 123 clinically stable subjects. Seventy five patients had COPD, of which 70.6% were men and 29.4% were women. Forty-eight subjects had asthma, comprised of 45.8% and 54.2%, men and women, respectively. Dyspnea was assessed with the use of modified Medical Research Council (mMRC) Visual Analogue Scale VAS, and BORG scale. All patients underwent spirometry with a broncho-reversibility test.

RESULTS

There were no differences in age for neither asthma patients, 56.5 ± 11.6 and 55.0 ± 12.7 (p = 0.5) for males and females, nor for COPD patients, 66.8 ± 9.0 and 66.8 ± 7.7 (p = 0.7) for males and females, respectively. Asthmatic females had more dyspnea than males when assessed with VAS, 1.85 ± 2.24 and 3.84 ± 2.80 (p = 0.01), for males and females, respectively. When assessed with BORGpre 6-MWT, dyspnea results were 0.86 ± 1.83 and 2.43 ± 2.31 (p = 0.005), for males and females, respectively. In the whole group, apart from FEV (for mMRC, VAS, BORGpre) and BMI (BORGpost) the severity of dyspnea was related to female sex when assessed with mMRC (OR=2.83; 95%CI: 1.25-6.42) and VAS (OR = 2.17; 95%CI:1.00-4.73).

CONCLUSIONS

Although more apparent in asthma, it was revealed for the first time, that sex has a strong influence on the magnitude of dyspnea perception, both in asthma and COPD. Therefore, sex related dyspnea sensation should probably be included in clinical assessment and patient treatment.