The hierarchy of copper status in paediatric enteral tube feeding: A comparative retrospective cohort study of jejunal and gastric feeding.

BACKGROUND & AIMS: Jejunal tube feeding (JTF) is associated with micronutrient deficiencies, including copper which is an essential trace element. Current paediatric guidelines recommend annual copper measurement in JTF patients based on limited evidence. We aimed to determine the rate of copper depletion and deficiency in a 21-year cohort of paediatric home JTF patients and compare outcomes with paediatric gastrostomy-fed patients.

METHODS

This was a retrospective cohort study in a tertiary paediatric specialist nutrition service. 76 JTF patients (2002-2023) were compared to 144 gastrostomy fed patients (2013-2023) who were categorised into simple (sGF) (n = 124) and complex (cGF) (n = 20) gastric groups based on underlying gastrointestinal comorbidities. All available copper levels were analysed in all groups with significant depletion defined as >10% below the lower limit of normal (LLN). Patients with consequential deficiency and those who received repletion were recorded. Multivariate logistic regression was used to identify independent risk factors for copper depletion.

RESULTS

The cGF group were most likely to have ever had copper depletion (25%), followed the JTF group (13%), then the sGF group (2.5%) (p=<0.005). On multivariate analysis, cGF (odds ratio (OR) 17.3, 95% confidence interval (CI) 2.81-116) and JTF (OR 6.27, 95% CI 1.82-28.9) were independently associated with depletion compared to sGF. Neurodisability (OR 5.41, 95% CI 1.29-39.0) was also an independent risk factor. Copper-deplete JTF patients had significantly lower absolute copper levels (median 8.7 μmol/L, interquartile range (IQR) 2.1-11.0) compared to 11.7 μmol/L (IQR 9.5-12.7) for the sGF group and 10.7 μmol/L (IQR 4.5-11.2) for the cGF group. JTF patients were more likely to develop cytopenia and require repletion compared to the gastrostomy fed groups. All deplete patients who received supplementation with gastric copper sulphate subsequently normalised their levels.

CONCLUSION

Both jejunally fed and gastrically fed patients with complex GI pathology are at a significantly increased risk of copper depletion compared to other gastrically fed patients. However, JTF patients experience more profound depletion and are more likely to develop consequential cytopenia and require copper repletion, likely due to bypassing of the usual mechanisms of digestion and absorption in the upper GI tract. These data support yearly copper measurement in JTF patients and we endorse extending screening to gastrostomy fed patients with relevant risk factors.