PURPOSE: Chronic Obstructive Pulmonary disease (COPD) is considered to be a systemic inflammatory disease, with increased levels of inflammatory mediators especially during acute episodes. However, the relationship of systemic inflammation with severity of acute exacerbation and mortality is not clear.
METHODS: Serum levels of C-reactive protein (CRP), Tumor necrosis factor alpha (TNF-alpha), and Interleukins 6 and 8 (IL-6, IL-8) were estimated within 24 hours of admission in patients with acute exacerbation of COPD (AECOPD). The levels of these inflammatory markers were compared between survivors and non-survivors, and between those who required/did not require mechanical ventilation.
RESULTS: Forty patients were evaluated (30 males; mean (SD) age, 60(10) years). 32 (80%) were current or former smokers, with a median (range) pack-years of 15 (0 to 112.5). The median (range) duration of COPD was 7 years (2 to 40 years). 50% patients had type I exacerbation. 24 patients (60%) required mechanical ventilation for a median duration of 1.5 days (range, 1 to 30), and 10 patients (25%) died in hospital. Mean Acute Physiology and Chronic Heath Evaluation (APACHE) II score was 13.0 ± 5.5. Serum levels of IL-6, IL-8, TNF-alpha (in pg/ml) and CRP (mg/dl)were higher in patients who survived compared to those who died (25.6 ± 46.1 vs 13.8 ± 19.9, p=0.27; 256.8 ± 614.6 vs 216.0 ± 628.8, p=0.86; 15.8 ± 64.9 vs 7.2 ± 22.9, p=0.54; and 6.7 ± 12.9 vs 4.6 ± 4.8, p=0.47 respectively); however, the difference was statistically insignificant. There was no significant difference in the levels of these markers between patients with mild/moderate and severe exacerbation, or between patients who required or did not require mechanical ventilation.
CONCLUSION: Survivors of AECOPD mount a higher inflammatory response compared to non-survivors. However, baseline serum CRP, TNF-alpha, IL-6, and IL-8 levels do not appear to be reliable markers of severity or mortality in AECOPD.
CLINICAL IMPLICATIONS: There is a need to evaluate other inflammatory mediators that may be more accurate in assessing severity or predicting mortality in patients with AECOPD.
DISCLOSURE: Randeep Guleria, None.