Adult Primary Ciliary Dyskinesia (PCD) has not been well characterised. Patients have varied radiological severity of disease and lung function impairment and limited data is available regarding prognosis. In this retrospective study we describe and characterise a large adult PCD cohort, and identify determinates of disease progression using longitudinal lung function data.
We retrospectively analysed 151 adult patients at a single tertiary centre. Overall mortality was 4.6% over a 7-year median follow-up period. Lung function decline was estimated at 0.49%FEV1predicted/year. Older age at diagnosis showed moderate negative correlation with FEV1%predicted at diagnosis (r = -0.30; p = 0.01) and increased Pseudomonas aeruginosa colonisation (p < 0.01) but not longitudinal FEV1%predicted (β = 0.001; (95% CI:-0.35,0.35)). Within multivariate mixed models of FEV1 adjusting for ciliary ultrastructure, HRCT scoring of severity of bronchial wall dilatation (p < 0.01) and extent of bronchiectasis (p = 0.03) showed evidence of modifying the decline in FEV1 with age. Lung function decline additionally differed by ciliary ultrastructure (p = 0.04) with patients with microtubular defects having the greatest decline.
Our study reveals a large proportion of adult PCD patients are diagnosed late with lower FEV1 and increased P. aeruginosa colonisation at diagnosis. Increased disease burden on HRCT and microtubular defects on ciliary ultrastructure predicts progressive lung function decline. This study highlights the need for early diagnosis alongside prospective multi-centre disease-specific trials to confirm triggers for lung function decline and identify potential novel therapeutic strategies.