L’absorption intestinale des vitamines hydrosolubles et liposolubles en pratique clinique

25 year experience of patterns of plasma vitamin C levels in patients requiring home parenteral support

OBJECTIVE

Vitamin C deficiency is common in patients with chronic intestinal failure. Risk factors are poorly understood and guidelines for monitoring largely based on expert opinion. The aim of this study was to describe patterns of vitamin C deficiency in patients on long-term home parenteral support (HPS).

DESIGN

A retrospective review of a prospectively collated database for 236 HPS patients cared for in Glasgow, from 1998 to 2023, was interrogated for subjects with paired CRP and vitamin C measurements. Following analysis of the impact of CRP on vitamin C levels, further review of associated clinical, micronutrient and dietetic details in those with a paired CRP <5 mg L-1 were used to identify risk factors for hypoascorbataemia.

RESULTS

1527 recorded episodes with paired CRP and vitamin C measurements were analysed. Period prevalence of hypoascorbataemia was between 29.3 and 52.5%, depending on choice of the lower reference range for vitamin C as either 15 μmol L-1 or 26.1 μmol L-1. The influence of CRP appeared most significant early during HPS with other factors, including extensive mucosal disease, precedent surgery or presence of a colostomy identified as more significant on multivariate analysis for those on long-term HPS (OR 1.3261-1.5609, 1.0752-1.1008, and 0.6260-0.6663 for threshold vitamin C of 26.1 or 15 μmol L-1 respectively).

CONCLUSION

Vitamin C may present differently in long term HPS patients in comparison to those in the acute phase of illness. An evidence based approach to guideline development should be promoted to reduce morbidity.

An evaluation of plasma vitamin C concentrations in individuals requiring home parenteral nutrition

BACKGROUND

Ascorbic acid (VitC) is an essential coenzyme to maintain health, but there are minimal data on the adequacy of VitC supply in patients requiring home parenteral nutrition (HPN).

METHODS

A prospective pilot study measuring plasma VitC, serum vitamins A,D,E and the minerals zinc, copper, selenium and magnesium in 28 adult HPN-dependent (≥6 months) patients was carried out.

RESULTS

57% of patients had insufficient VitC status. There was a strong, positive correlation between HPN provision of VitC and plasma VitC concentrations (r_s =0.663, p=0.00) with 83% insufficiency rate below a provision of 800mg/week. There was no association seen between plasma VitC and number of HPN days/week (p=0.539); number of months on HPN (p=0.773) or dependency on HPN (86±31% of energy requirements met via HPN v 77±23%, p=0.39).

CONCLUSIONS

VitC insufficiency is prevalent in HPN-dependent patients. Our data highlight the need for regular monitoring of VitC in those living with type III intestinal failure. This article is protected by copyright. All rights reserved.