Correlation between bronchodilator responsiveness and quality of life in chronic obstructive pulmonary disease

Guidelines and literature debate the importance of testing for bronchial reversibility and its total significance is unclear. Clinically, patients with greater reversibility have higher fluctuations in respiratory symptoms, and hence may have a reduced health-related quality of life (HRQoL). On the other hand, they may have a better HRQoL as medications may be more effective in this population. Presently, there are no reports concerning the relationship between HRQoL as an indicator of therapy and reversibility. We hypothesized that the reversibility of airflow limitation might be correlated with the HRQoL in COPD.

We examined 63 subjects with COPD (mean age: 71.7 years). Reversibility was measured by the change in FEV1 and FVC after the inhalation of salbutamol (300 microg), and we investigated the relationship between the reversibility and the parameters of HRQoL, which included St. George's Respiratory Questionnaire (SGRQ), Visual analogue scale-8 (VAS-8), Short-Form 36-Item Health Study, Basic activities of daily living, Instrumental activities of daily living, and the Oxygen cost diagram.

Post-bronchodilator FEV1, % predicted was positively correlated with both the total scores of SGRQ and VAS-8 (p<0.0001 and p<0.006, respectively). Furthermore, the reversibility of FVC was positively correlated with all items of the SGRQ, except for impact (total score: p<0.02; symptoms: p<0.02; activity, p<0.05; total score of VAS-8: p<0.02). However, the reversibility of FEV1 was neither correlated with the total score nor any items in the scales.

Those who have FVC that respond to bronchodilator at rest might result in an improvement of HRQoL after treatment.