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

BACKGROUND

Patients with CF treated for pulmonary exacerbations (PEx) may experience faster subsequent declines in FEV. Additionally, incomplete recovery to baseline FEV occurs frequently following PEx treatment. Whether accelerated declines in FEV are preceded by poor PEx recovery has not been studied.

METHODS

Using 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 FEV recorded within the 6months before and 3months after the PEx. We defined poor PEx recovery as the best FEV in the 3months after the PEx <90% of the best FEV in the 6months before the PEx. We calculated mean (95% CI) hazard ratios (HR) of having >5% predicted/year FEV decline and poor PEx recovery using multi-state Markov models.

RESULTS

From 13,954 PEx, FEV 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 FEV decline, HR 0.41 (0.37, 0.46), than patients who recovered to >90% of baseline FEV following PEx treatment.

CONCLUSIONS

Accelerated declines in FEV are more likely to precede a PEx with poor recovery than to occur in the following year. Preventing or halting declines in FEV may also have the benefit of preventing PEx episodes.