Clinical, functional and biochemical changes during recovery from COPD exacerbations

The pathways underlying chronic obstructive pulmonary disease exacerbations (ECOPD) remain unclear. This study describes the clinical, functional and biochemical changes during recovery from ECOPD.

Thirty hospitalized patients with Anthonisen's type-I ECOPD were evaluated on days 0 (admission), 3, 10 and 40. A five-symptom score (TSS), performance status and quality of life were evaluated. Post-bronchodilator spirometry, blood gases, oxidative stress, C-reactive protein (CRP), serum amyloid-A (SAA), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and fibrinogen were also measured. Patients were classified as early- or late-recoverers, based on whether dyspnea had returned to pre-exacerbation level by day 10.

Most clinical, functional and biochemical parameters improved during follow-up. CRP and IL-6 levels reduced on Day 3 (p<0.05), whereas SAA on Day 10 (p<0.01). TNF-α was reduced on Days 3 and 10, but on Day 40 its levels returned to baseline. Fibrinogen and WBC reduced only by day 40. TSS and dyspnea were correlated inversely with FEV1 on days 3, 10 and 40. Although late-recoverers had lower FEV1 on admission, none of the reported measurements on admission and day 3 predicted early recovery.

During recovery from ECOPD, symptomatic improvement correlates only with post-bronchodilator FEV1 whereas systemic inflammatory burden subsidence does not correlate with clinical and functional changes. Although late-recoverers have lower FEV1 on admission, none of the measured parameters is able to predict early symptomatic recovery.