Characterising nutrition status in a regional cohort of children with primary ciliary dyskinesia

Abstract

Introduction: Primary ciliary dyskinesia (PCD) is a rare, heterogeneous genetic disorder where impaired mucociliary clearance is caused by dysfunctional motile cilia. There is limited characterisation of the nutritional status of children with PCD but one recent paper found that lower body mass index (BMI) was associated with worse lung function (FEV1). Bioimpedance spectroscopy (BIS) has been used to identify patients at risk of needing nutritional intervention but this has not been assessed in PCD patients. Aim To assess, in depth, the nutritional status of children with PCD. Methods: All children (n=40) with PCD, <16 years, from a single tertiary centre, University Hospital Southampton (UK), seen between September 2016 and April 2017 were prospectively enrolled. We collected data on clinical phenotype, anthropometry, BIS measurements, nutritional intake and blood samples. Results: There was a significant difference in height for age z score between children with a FEV1 of -2 z scores (mean (SD) -0.49 z scores (±1.1) vs. 0.2 a score (±0.7), p=0.05. Significant differences were seen in BIS measurements (bioelectrical phase angle 500) in children with a fat free mass index -2 z scores (p=0.002), these patients would not have been identified as at nutritional risk by BMI alone. PCD patients had a higher incidence of Vitamin D insufficiency (<50nmol/L) (44%) and deficiency (<30mmol/L) (21%) than previously reported for healthy and PCD cohorts. Conclusions Monitoring Vitamin D levels is important in PCD patients. We hypothesise that nutritional intervention in at risk children with PCD will have a positive impact on important clinical outcome measures, such as BMI and FEV1. However, such strategies will need to target linear growth failure and the promotion of lean body mass acquisition. BIS might allow for early identification of at risk children but requires further assessment.