Reversibility at pulmonary function tests: can it have implications in patients with COPD?

Abstract

Background: Reversibility is usually used for the differentiation between asthma and COPD, but actually can it be used for the prediction of treatment response?

Materials and methods: 81 patients was included into the study. We collected medical history, body composition, mMRC, CAT, SGRQ, PFT. Patients were divided into 2 groups – low-reversibility group (LR) with ≤ 6 % FEV1 improvement, and high-reversibility group (HR) - > 6 %. Re-assessment was performed in 3 months.

Results: 39 (48.1 %) patients were in LR, and 42 patients (51.9 %) in HR. Average age: 63.7±5.6 in LR; 65.6±5.9 in HR. Smoking history: 26.7±3.9 in LR; 18.6±3.8 in HR (p<0.01). Exacerbation history: 3.01±0.54 in LR; 2.04±0.44 in HR (p<0.01), with hospital admissions: 1.91±0.38 in LR; 1.38±0.24 in HR (p<0.05). COPD duration:12.09+2.77 years in LR and 13.54±2.87 in HR (p>0.05). LR group had higher incidence of CAD and DM compared to HR group. There were comparable data regarding questionnaires on visit 1 (p>0.05), both groups improved their score between the visits (p<0.01). Patients of HR groups demonstrated significant difference in SGRQ and CAT questionnaires at visit 2 when compared to LT group. No difference between the groups in body composition (p>0.05). PFT values were similar between the groups. But FEV1 reversibility was 9.7±2.2% in HR and 2.7±2.5% in LR (p<0.01). HR also showed a 6.25±1.27 % FEV1 increase between the visits, when compared to 2.1±1.2 % in LR (p<0.01).

Conclusions: Patient with low-reversibility has longer smoking history (p<0.01); more exacerbations and hospitalizations(p<0.01), co-morbidities. Also they demonstrate worse response to treatment according to PFT data.