Abstract
Background: The COPD assessment test (CAT) is widely used for basic symptom evaluation in patients with COPD. The impact of COPD phenotypes on symptom scores using the CAT, however, remains largely unknown.
Methods: The POPE-Study (NCT02119494) is an international, multicentre, observational cross-sectional survey of consecutive patients with COPD in Central and Eastern Europe (CEE). Respiratory symptoms using the modified Medical Research Council (mMRC) dyspnoea scale, and the CAT were recorded. Inclusion criteria: age ≥ 40 years, smoking history ≥ 10 pack-years, post-bronchodilator (BD) FEV1/FVC < 0.7, and ≥ 4 weeks absence of exacerbation. The relationship between predefined phenotypes and CAT score items was assessed. In addition to total CAT score, all eight CAT sub-items (CAT 1 – CAT 8) are separately noted.
Results: 3366 COPD subjects (66 ± 8.8 yrs, post-BD FEV1 52.8 ± 18.5 % predicted, CAT 17.4 ± 7.8) were recruited. On the whole 63.3 % were non-exacerbators (NON-AE), 20.4 % frequent exacerbators with chronic bronchitis (AE CB), 9.5 % frequent exacerbators without CB (AE NON-CB), and 6.9 % were patients with asthma-COPD overlap syndrome (ACOS). There were apparent statistically significant differences (< 0.001) in total CAT and individual items of the score between phenotypes. According to results of univariate and multivatriate logistics regression some items of CAT scores are good predictors of COPD phenotypes, e.g. if CAT 3 tightness on chest grew by 1 point, probability of being non-exacerbator was 10-20% lower.
Conclusion: There were noted significant differences in total CAT and individual CAT items between clinical phenotypes of COPD.
- Copyright ©the authors 2016
