Effect of a single exacerbation on decline in lung function in COPD.
BACKGROUND
COPD exacerbations are associated with accelerated lung function decline, but whether they are causal is unknown. We evaluated the effect of a single exacerbation on rate of lung function change using data from the 4-year Understanding Potential Long-term Impacts on Function with Tiotropium (UPLIFT®) trial.


METHODS
Retrospective analysis of annual rates of decline in FEV1 and FVC before and after a single (and the only) moderate-to-severe exacerbation in patients during UPLIFT® (exacerbator subgroup), compared with changes between the first and second half of the study in a non-exacerbator subgroup. A sensitivity analysis examined annual rates of decline in matched pairs of exacerbators and non-exacerbators.


RESULTS
Following the single moderate-to-severe exacerbation, mean annual decline in post-bronchodilator lung function increased compared with the rate of decline before the exacerbation (FEV1 76.5 vs. 39.1 mL/year, p = 0.003; FVC 106.5 vs. 34.7 mL/year, p = 0.011). In non-exacerbators, there were no differences in rates of decline between the first and second halves of the study (post-bronchodilator FEV1 38.2 vs. 41.8 mL/year, FVC 45.3 vs. 43.9 mL/year. Before the single (moderate-to-severe) exacerbation in the exacerbator subgroup, declines in post-bronchodilator FEV1 or FVC were similar to non-exacerbators in the first half of the study; after the single exacerbation they were significantly higher than for non-exacerbators in the second half of the study. The sensitivity analysis showed similar results.


CONCLUSION
A single COPD exacerbation may result in significant increase in the rate of decline in lung function.
['Halpin|David M G|DMG|', 'Decramer|Marc|M|', 'Celli|Bartolome R|BR|', 'Mueller|Achim|A|', 'Metzdorf|Norbert|N|', 'Tashkin|Donald P|DP|']
D000280:Administration, Inhalation D000305:Adrenal Cortex Hormones D058666:Adrenergic beta-2 Receptor Agonists D000368:Aged D001993:Bronchodilator Agents D018450:Disease Progression D005260:Female D005541:Forced Expiratory Volume D006801:Humans D008297:Male D008875:Middle Aged D010276:Parasympatholytics D029424:Pulmonary Disease, Chronic Obstructive D012129:Respiratory Function Tests D012189:Retrospective Studies D012602:Scopolamine Derivatives D012907:Smoking D000069447:Tiotropium Bromide D016896:Treatment Outcome D014797:Vital Capacity
Exacerbation COPD Lung function decline Understanding Potential Long-term Impacts on Function with Tiotropium Tiotropium Bronchodilator PFT Pulmonary function test UPLIFT(®)