Serum Zinc Concentrations in Cystic Fibrosis Patients Aged Above 4 Years: A Cross-sectional Evaluation

Abstract

Aim: Assess the risk of zinc (Zn) deficiency in the older cystic fibrosis (CF) population. Method:Cross sectional investigation of all CF patients above the age of 4 followed at the Ghent university centre between 2002 and 2003. Data on age, weight and height z-score, pancreatic and pulmonary functions, chronic pseudomonas infection and CF transmembrane conductance regulator (CFTR) mutations were collected. Serum Zn, vitamin A, E, retinol binding protein (RBP), albumin, sedimentation rate, total IgG and cholesterol were determined. Serum Zn was compared with a local healthy control group (1) and with literature data (3). Results: 101 patients (median age 16 years) were included. There was no difference in serum Zn concentration between CF patients and controls. In CF patients no difference in serum Zn concentration between pancreatic sufficient or insufficient patients was seen. Serum Zn was not associated to nutritional status or height Z-score. A significant association serum Zn to serum albumin (p< 0.0005) and to vitamin A (p< 0.01) was seen. No associations of serum Zn to serum vitamin E, RBP, cholesterol or CFTR were present. There is a significant association serum Zn -forced vital capacity (p<0.01). Serum Zn was not associated to inflammatory parameters or chronic pseudomonas infection. Conclusion: Comparison of CF patients with local controls revealed no significant differences. However, since persisting steatorrhoea increases Zn loss (2) and 12.6% of our population has a serum Zn below the P 2.5 value of the NHANES II study (3), there could remain an increased risk of Zn deficiency in some CF patients. Further on the association with pulmonary function needs more investigation.

The Effect of Zinc Supplements in Cystic Fibrosis Patients

“…Further striking clinical features were loss of appetite and stunted growth. The serum Zn concentrations in our CF patients are rather low when compared to the literature [16] but also our healthy control population had the same low serum Zn concentrations [21] . As shown in our recent report on this subject, only the patients with pancreatic insufficiency had decreased serum Zn concentrations below 65 g/dl, the lower 'normal' (p = 2.5) serum Zn value of the NHANES II study [16,22] .…”

“…Comparisons were made with a not supplemented control CF population with higher levels of serum Zn [16] and a randomly selected age-matched control CF subgroup.…”

“…Earlier we reported the results of a cross-sectional examination of our CF population [4,16] . Among them we identified a cohort of severely affected children, presenting severe pancreatic insufficiency, loss of appetite, low nutritional intake and stunted growth combined with low serum Zn values [4,16] .…”

“…Among them we identified a cohort of severely affected children, presenting severe pancreatic insufficiency, loss of appetite, low nutritional intake and stunted growth combined with low serum Zn values [4,16] . No relation with the genotype was obvious, but very low serum Zn concentrations were a main characteristic of pancreatic insufficiency.…”

Zinc Supplementation for One Year Among Children with Cystic Fibrosis Does Not Decrease Pulmonary Infection

“…However, no such relation was found in the study on 36 children with cystic fibrosis by Van Biervliet et al 14 Another study reported that serum zinc levels in children with cystic fibrosis were similar to those of normal controls but that children with lower serum zinc levels had significantly worse results on the pulmonary function tests. 15 An increase has been observed in the sputum zinc levels in pulmonary exacerbations, and a decrease has been observed in the levels after treatment in bronchiectasis (cystic fibrosis and non-cystic fibrosis bron- chiectasis); however, the significance of this remains unclear. 16 Tinley et al 17 observed an interaction between the serum zinc and vitamin levels.…”