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Impairment of nasal mucociliary clearance in former smokers with stable chronic obstructive pulmonary disease relates to the presence of a chronic bronchitis phenotype.

BACKGROUND
Associations between nasal and bronchial impairment have been repeatedly described in chronic obstructive pulmonary disease (COPD), whereas nasal mucociliary clearance (MCC) in COPD patients is not yet fully understood. We studied nasal MCC parameters in COPD patients and compared them with healthy adults (HA) and with cystic fibrosis (CF) patients with compromised MCC.


METHODOLOGY
An observational study of 98 COPD ex-smokers and subjects from control groups evaluated for nasal MCC time (NMCCt) and by digital video microscopy of nasal mucosa recording ciliary beat frequency (CBF) and ciliary beat pattern.


RESULTS
The NMCCt was decreased in HA compared to those with COPD and decreased in those with COPD compared to those with CF. CBF in COPD was lower compared to HA. The index of ciliary dyskinesia in COPD patients differed from HA. We detected higher NMCCt and lower nasal CBF in patients with chronic bronchitis phenotype (CB) compared to non-CB patients.


CONCLUSIONS
We confirmed the presence of impaired nasal MCC in COPD ex-smokers. These impairments were apparent predominantly in the CB phenotype.