Poor recovery from a pulmonary exacerbation does not lead to accelerated FEV1 decline

Abstract

BackgroundPatients with CF treated for pulmonary exacerbations (PEx) may experience faster subsequent declines in FEV1. Additionally, incomplete recovery to baseline FEV1 occurs frequently following PEx treatment. Whether accelerated declines in FEV1 are preceded by poor PEx recovery has not been studied. MethodsUsing 2004 to 2011 CF Foundation Patient Registry data, we randomly selected one PEx among patients ≥6years of age with no organ transplantations, ≥12months of data before and after the PEx, and ≥1 FEV1 recorded within the 6months before and 3months after the PEx. We defined poor PEx recovery as the best FEV1 in the 3months after the PEx <90% of the best FEV1 in the 6months before the PEx. We calculated mean (95% CI) hazard ratios (HR) of having >5% predicted/year FEV1 decline and poor PEx recovery using multi-state Markov models. ResultsFrom 13,954 PEx, FEV1 declines of >5% predicted/year were more likely to precede poor spirometric recovery, HR 1.17 (1.08, 1.26), in Markov models adjusted for age and sex. Non-Responders were less likely to have a subsequent fast FEV1 decline, HR 0.41 (0.37, 0.46), than patients who recovered to >90% of baseline FEV1 following PEx treatment. ConclusionsAccelerated declines in FEV1 are more likely to precede a PEx with poor recovery than to occur in the following year. Preventing or halting declines in FEV1 may also have the benefit of preventing PEx episodes.