Copper and Copper/Zinc Ratio in a Series of Cystic Fibrosis Patients

Abstract

Cystic fibrosis (CF) patients require a stable and sufficient supply of micronutrients. Since copper is an essential micronutrient for human development, a cross-sectional study was carried out to investigate the serum copper levels, serum copper/zinc (Cu/Zn) ratios, and their relationship with nutritional indicators in a group of CF patients. Anthropometric, biochemical, and dietary measurements, an abdominal ultrasound, and respiratory and pancreatic tests were conducted. Seventeen CF patients were studied (10 females, 59%), 76.5% of whom were ∆F580. Their mean serum copper (113 ± 23 μg/dL) was normal, and there was only one teenager with hypocupremia (6%) and two children with hypercupremia (18%). A significant association between serum copper and zinc levels was discovered. The Cu/Zn ratio was higher than 1.00 for 94% of patients, which is an indicator of an inflammation status. There was no significant correlation between the serum copper concentrations and respiratory and pancreatic function, respiratory colonization, and the results of the abdominal ultrasound. Linear regression analysis showed that serum copper had a positive association with both the Z-score body mass index (BMI) and mean bone conduction speed (BCS). Therefore, since 94% of CF patients had a Cu/Zn ratio > 1.00, this factor must alert us to consider the risk of zinc deficiency and high inflammatory response. The measurement of serum zinc alone does not show one’s zinc status. However, the Cu/Zn ratio may be an indicator of zinc deficiency and the inflammatory status of CF patients.

Copper and Copper/Zn Ratio in a Series of Children with Chronic Diseases: A Cross-Sectional Study

“…Results showed that serum Cu and the Cu/Zn ratio had an inverse and significant correlation with age. Serum copper and zinc levels had a direct association when they were adjusted by age (Figure 2), and linear regression analysis showed that serum Cu decreased significantly with age (Figure 3), as observed in a previous study conducted in a series of CF patients [27]. Furthermore, the mean serum copper and the Cu/Zn ratios were significantly higher in children than adolescents, and the probability of finding altered Cu levels and hypercupremic cases in children (OR 3.6 and 14), children under 5 years (OR 5.8 and 7.3), and under 5 age-for-50 • Height (OR 4.4 and 6.9) was higher than in adolescents, children >5 years, and children >5 age-for-50 • Height, respectively.…”

“…Up to now, pediatric reference intervals for serum Cu have often been difficult to set up [43]. In our series of patients with chronic disease aged from 1 to 19, the mean serum Cu (118 µg/dL) was normal and there was no significant difference with the mean serum copper in a series of CF patients (113 µg/dL, p = 0.001) [27]. However, our mean serum Cu was significantly lower compared to the mean serum Cu of the German study carried out in children aged between 1 month to 18 years (20.4 ± 4.9 µmol/L or 129.6 µg/dL, p = 0.001) [44], and the study conducted in 120 healthy children (1 to 18 years of age) (134.5 µg/dL, p = 0.000) who did not receive any vitamins and mineral supplements [7] as in our series.…”

“…It is necessary to highlight that, in a series of CF patients, there was a direct association between serum Cu levels and BMI [27]. Similarly, Abiaka et al reported that Cu levels were positively associated with BMI values (r = 0.302, p < 0.001) in a group of Arabs [53].…”

“…Regarding gender, some studies found no statistically significant differences in serum Cu in healthy children [50], but other studies revealed that women had significantly higher serum Cu than men [27,51,52]. In 560 Kuwaitis (15-80 years), Cu in females (158 µg/dL) was significantly higher than in males (133 µg/dL, p < 0.0001) [53].…”

“…Participants were classified by nutritional status into eutrophic, obesity, and undernutrition groups using BMI. Cystic fibrosis (CF) patients [26,27], acute infection, hospitalization, and refusal to take part were exclusion criteria. The time of chronic diseases was shown in months.…”