Static hyperinflation and respiratory disability were associated with frequent-exacerbation phenotype in patients with severe COPD

Background: acute exacerbations are very important events in the clinical history of COPD because are responsible for the decline in lung function. Aims and objectives: we aim to identify whether there are any clinical and functional features of frequent exacerbators in severe COPD patients. Methods: we assessed an observational, cross sectional, case control cohort study. All subjects had GOLD stage 3 or 4. “Frequent exacerbators” (n = 183) reported a number of >2 exacerbations in the last 12 months or > 1 with hospitalization and “infrequent exacerbators” (n = 162) had <1 exacerbations over the last 12 months without hospitalization. Results: no significant differences were found in age, sex, body mass index, presence of chronic cough, six minute walking test and Charlson Comorbidity Index between the two groups. Frequent exacerbators had significantly lower inspiratory capacity (IC) % of predicted and higher residual volume/total lung capacity (RV/TLC) ratio. Infrequent exacerbators had lower mMRC score and BODE index than frequent exacerbators. In the multivariate model an increase of RV/TLC ratio and mMRC score were independently associated with frequent exacerbations. Conclusions: static hyperinflation and respiratory disability, misured by mMRC score, were independently associated w ith frequent exacerbations in severe COPD patients.