Characteristics and outcomes of adults with primary ciliary dyskinesia (PCD): an EMBARC/BEAT-PCD analysis

Introduction: PCD is an inherited cause of bronchiectasis. Little is known about epidemiology and disease course in adults compared to other patients with bronchiectasis. Methods: A multi-centre European bronchiectasis registry (EMBARC) was used to identify new insights into the epidemiology of PCD. Multivariable models were adjusted for age, sex, lung function, region and treatments. Results: 523/18927 adult patients with bronchiectasis had a diagnosis of PCD. In comparison with other aetiologies of bronchiectasis, patients with PCD were significantly younger, with lower FEV1% pred., more frequent exacerbations and chronic infection with Pseudomonas aeruginosa, Haemophilus influenzae and other pathogens. Radiological severity was greater. Adherence to guideline recommended care was higher in PCD vs the general bronchiectasis population. In addition to higher use of physiotherapy, PCD patients with >3 exacerbations/yr were more likely to receive macrolides (37% vs 20%), inhaled antibiotics (30% vs 11%) and any antibiotic prophylaxis (65% vs 37%). PCD patients were more likely to receive P.aeruginosa eradication treatment (74% vs 67%) and to have sputum samples sent when clinically stable (81% vs 59%). p<0.0001 for all comparisons. In long term follow-up, PCD patients were not at higher risk of exacerbations, hospitalizations, FEV1 decline or mortality after adjustment for confounders. Conclusion: PCD patients have more severe bronchiectasis, but similar long term outcomes to other bronchiectasis patients most likely because they receive higher quality care. The better care received emphasises the importance of making a PCD diagnosis even in the absence of PCD specific therapies.