Prevalence of vitamin C deficiency in adult hospital patients in high-income countries: A scoping review.

Abstract

Rationale: With emerging evidence indicating vitamin C deficiency (VCD) is present in community settings of high-income countries, there is growing interest in understanding the prevalence of VCD during hospitalisation, in order to prevent deficiency progression to scurvy and other clinical outcomes associated with VCD. This study aimed to explore the prevalence of VCD in adult hospitalised patients, describe patient characteristics, and identify associated risk factors and clinical outcomes. Method(s): A systematic scoping review was conducted following the PRISMA-ScR framework. Six databases were searched. Eligibility included hospital inpatients in high-income countries and VCD prevalence using World Health Organisation reference standards (plasma/serum concentration <11.4 mumol/L, whole blood <17 mumol/L). Cumulative prevalence of VCD in pooled studies was calculated using REVMAN 5.4. Result(s): Twenty-two studies from 8 countries were included, representing 23 articles. Cumulative prevalence of VCD was 26.6% (95% CI: 20.7-32.5; n=2494), prevalence was highest in patients with severe illness and poor nutrition status, and scurvy was present in 18-48% (n=581) of VCD patients. VCD status did not resolve during admission unless therapeutically replaced. Being retired (p=0.015), and taking excessive alcohol and tobacco (p=0.0003) were independent risk factors for VCD (n=184); clinical outcomes included increased risk of frailty (aOR 4.3, 95% CI 1.33-13.86, p=0.015) and cognitive impairment (aOR 2.93, 95% CI 1.05-8.19, p=0.031; n=160). Two studies examined nutrition associations with VCD (n=309); results were inconsistent. Conclusion(s): High prevalence of VCD exists in adult hospitalised patients in high-income countries. Research which focuses on early detection, and examination of VCD prevalence in a broader range of hospital settings and patient groups is warranted. Disclosure of Interest: None declaredCopyright © 2023