Vitamin C deficiency after kidney transplantation: a cohort and cross-sectional study of the TransplantLines biobank.

PURPOSE: Vitamin C deficiency is associated with excess mortality in kidney transplant recipients (KTR). We aim to evaluate plasma vitamin C status at different post-transplantation moments and assess the main characteristics associated with vitamin C deficiency in KTR. METHODS: Plasma vitamin C was assessed in 598 KTR at 3-, 6-, 12-, 24-, and 60-months post-transplantation, 374 late KTR with a functioning graft ≥ 1 year, and 395 potential donors. Vitamin C deficiency was defined as plasma vitamin C ≤ 28 µmol/L. Diet was assessed by a 177-item food frequency questionnaire. Data on vitamin C-containing supplements use were extracted from patient records and verified with the patients. RESULTS: Vitamin C deficiency ranged from 46% (6-months post-transplantation) to 30% (≥ 1 year post-transplantation). At all time points, KTR had lower plasma vitamin C than potential donors (30-41 µmol/L vs 58 µmol/L). In cross-sectional analyses of the 953 KTR at their first visit ≥ 12 months after transplantation (55 ± 14 years, 62% male, eGFR 55 ± 19 mL/min/1.73 m2), the characteristics with the strongest association with vitamin C deficiency were diabetes and smoking (OR 2.67 [95% CI 1.84-3.87] and OR 1.84 [95% CI 1.16-2.91], respectively). Dietary vitamin C intake and vitamin C supplementation were associated with lower odds (OR per 100 mg/day 0.38, 95% CI 0.24-0.61 and OR 0.21, 95% CI 0.09-0.44, respectively). CONCLUSION: Vitamin C deficiency is frequent among KTR regardless of the time after transplantation, especially among those with diabetes and active smokers. The prevalence of vitamin C deficiency was lower among KTR with higher vitamin C intake, both dietary and supplemented. Further research is warranted to assess whether correcting this modifiable risk factor could improve survival in KTR.

Ascorbic acid deficiency amongst spondylodiscitis patients.

BACKGROUND: Spondylodiscitis can be a disabling and life-threatening infection. Ascorbic Acid is crucial for neutrophil function and collagen formation. Its association and clinical relevance in spondylodiscitis has not been previously examined. AIMS: To determine the prevalence, characteristics, and clinical outcomes of spondylodiscitis patients with Ascorbic Acid deficiency. METHODS: Sixty-eight consecutive patients admitted with spondylodiscitis, between December 2021 and August 2023 were included. Clinical characteristics, Ascorbic Acid levels and clinical outcomes were evaluated. RESULTS: Thirty-seven patients had Ascorbic Acid levels taken during admission. The median initial Ascorbic Acid level was 15 µmol/L with an IQR 6.5-27 µmol/L. Depletion defined as <28 µmol/L was present in 78% of patients. Deficiency defined as ≤11 µmol/L was present in and 46% of patients. Patients with depletion were more likely to require Intensive Care Admission (absolute risk increase = 24.1%; 2.6%-45.7%). Fifteen patients had repeat serum levels taken during admission with median increase of 17 µmol/L and an IQR 0-26 µmol/L. Patients that received supplementation had a significantly greater increase in Ascorbic Acid levels compared with those that did not receive supplementation (P = 0.002). CONCLUSION: Ascorbic acid deficiency is highly prevalent amongst spondylodiscitis patients. Depletion was associated with worse outcomes. Replacement significantly increased serum levels in comparison to standard hospital diet. The clinical significance of replacement remains to be evaluated.

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.

Mild Vitamin C Deficiency Is Common in the Inpatient Psychiatric Setting.

Objective: Mild vitamin C deficiency is a psychiatrically relevant nutritional state, with symptoms including apathy, fatigue, and low mood. Although complete vitamin C deficiency has largely been eradicated, mild deficiency remains common in certain populations. Here, we aimed to identify the prevalence of mild vitamin C deficiency in the inpatient psychiatric setting.Methods: We identified 221 patients with plasma vitamin C levels collected on an inpatient psychiatric unit serving a metropolitan area between January 1, 2015, and March 7, 2022. We identified demographic (age, sex, race, housing status, Area Deprivation Index [an index of neighborhood disadvantage]), substance use (tobacco use, alcohol use), diagnostic (depressive, bipolar, psychotic, anxiety, substance use, catatonia, neurocognitive, autism spectrum), and micronutrient (folate, vitamin B12, vitamin D) risk factors. DSM-5-TR was used as the diagnostic system. Bayesian log-normal regressions were constructed to predict vitamin C as a function of these risk factors. We used these same models to predict vitamin C as a function of significant risk factors.Results: We found that 64% (141 of 221; 95% confidence interval 57%-70%) of patients met criteria for mild vitamin C deficiency. While we did not identify robust demographic, substance use, or diagnostic-based risk factors, we found that folate and vitamin D strongly predicted vitamin C levels. To test the utility of these predictors, we simulated vitamin C as a function of folate and vitamin D and found that predicted deficiency remained high (∼ 50%-55%), even when folate/vitamin D were sufficiently replete.Conclusions: We find that vitamin C deficiency is highly prevalent in the inpatient psychiatric setting and remains high even when the relevant risk factor profile is favorable.

What We Are Missing: Using Machine Learning Models to Predict Vitamin C Deficiency in Patients with Metabolic and Bariatric Surgery.

PURPOSE: Vitamin C (VC) is implicated in many physiological pathways. Vitamin C deficiency (VCD) can compromise the health of patients with metabolic and bariatric surgery (patients). As symptoms of VCD are elusive and data on VCD in patients is scarce, we aim to characterize patients with measured VC levels, investigate the association of VCD with other lab abnormalities, and create predictive models of VCD using machine learning (ML). METHODS: A retrospective chart review of patients seen from 2017 to 2021 at a tertiary care center in Northeastern USA was conducted. A 1:4 case mix of patients with VC measured to a random sample of patients without VC measured was created for comparative purposes. ML models (BayesNet and random forest) were used to create predictive models and estimate the prevalence of VCD patients. RESULTS: Of 5946 patients reviewed, 187 (3.1%) had VC measures, and 73 (39%) of these patients had VC<23 µmol/L(VCD. When comparing patients with VCD to patients without VCD, the ML algorithms identified a higher risk of VCD in patients deficient in vitamin B1, D, calcium, potassium, iron, and blood indices. ML models reached 70% accuracy. Applied to the testing sample, a "true" VCD prevalence of ~20% was predicted, among whom ~33% had scurvy levels (VC<11 µmol/L). CONCLUSION: Our models suggest a much higher level of patients have VCD than is reflected in the literature. This indicates a high proportion of patients remain potentially undiagnosed for VCD and are thus at risk for postoperative morbidity and mortality.

Prevalence and prognostic significance of vitamin C deficiency in patients with acute upper gastrointestinal bleeding: a prospective cohort study.

BACKGROUND: Vitamin C is an essential dietary nutrient important for collagen synthesis, including within the gastrointestinal tract. AIM: We aimed to document the prevalence of Vitamin C deficiency (VCD) in patients who present with upper gastrointestinal bleeding (UGIB) and its association with clinical outcomes. METHODS: We conducted a prospective cohort study of patients presenting with UGIB. Fasting Vitamin C levels were collected at admission. Primary outcomes were the prevalence of VCD (Vitamin C level <23 µmol/L, severe VCD < 12 µmol/L) and a composite outcome of adverse events, stratified by VCD status. Secondary outcomes were prolonged hospitalisation and the need for ICU admission. RESULTS: A total of 227 patients were included (mean age 64.5 years, males 63.9%). VCD was identified in 74 (32.6%) and severe deficiency in 32 (14.1%) patients. VCD was associated with a higher composite endpoint of AE (45.9% vs 24.8%, p < 0.01), higher in-hospital mortality (9.5% vs 1.3%, p < 0.01), increased prolonged admissions (62.2% versus 47.1%, p = 0.03) and increased rebleeding (17.6% vs 7.8%, p = 0.03), compared with patients with normal Vitamin C levels. Multivariate logistic regression models showed that VCD was independently associated with the composite endpoint of AE. CONCLUSION: VCD is highly prevalent in patients with UGIB and associated with poorer outcomes, including higher mortality, rebleeding and length of stay. Interventional studies are required to determine the impact of early Vitamin C supplementation on clinical outcomes.

Prevalence and factors associated with vitamin C deficiency in inflammatory bowel disease.

BACKGROUND: Patients with inflammatory bowel disease (IBD) are prone to several nutritional deficiencies. However, data are lacking on vitamin C deficiency in Crohn's disease (CD) and ulcerative colitis (UC) patients, as well as the impact of clinical, biomarker and endoscopic disease severity on the development of vitamin C deficiency. AIM: To determine proportions and factors associated with vitamin C deficiency in CD and UC patients. METHODS: In this retrospective study, we obtained clinical, laboratory and endoscopic data from CD and UC patients presenting to the IBD clinic at a single tertiary care center from 2014 to 2019. All patients had an available plasma vitamin C level. Of 353 subjects who met initial search criteria using a cohort discovery tool, 301 ultimately met criteria for inclusion in the study. The primary aim described vitamin C deficiency (≤ 11.4 µmol/L) rates in IBD. Secondary analyses compared proportions with deficiency between active and inactive IBD. Multivariate logistic regression analysis evaluated factors associated with deficiency. RESULTS: Of 301 IBD patients, 21.6% had deficiency, including 24.4% of CD patients and 16.0% of UC patients. Patients with elevated C-reactive protein (CRP) (39.1% vs 16.9%, P < 0.001) and fecal calprotectin (50.0% vs 20.0%, P = 0.009) had significantly higher proportions of deficiency compared to those without. Penetrating disease (P = 0.03), obesity (P = 0.02) and current biologic use (P = 0.006) were also associated with deficiency on univariate analysis. On multivariate analysis, the objective inflammatory marker utilized for analysis (elevated CRP) was the only factor associated with deficiency (odds ratio = 3.1, 95% confidence interval: 1.5-6.6, P = 0.003). There was no difference in the presence of clinical symptoms of scurvy in those with vitamin C deficiency and those without. CONCLUSION: Vitamin C deficiency was common in IBD. Patients with elevated inflammatory markers and penetrating disease had higher rates of vitamin C deficiency.

Vitamin C Deficiency in Critically Ill Children: Prospective Observational Cohort Study.

OBJECTIVES: To evaluate the presence of vitamin C deficiency in critically ill children admitted to the PICU. DESIGN: Single-center prospective observational cohort study. SETTING: A 28-bed PICU and a pediatric outpatient sedation room of a tertiary-care teaching hospital. PATIENTS: Two pediatric patient groups 0-21 years old were studied: a PICU group and a group receiving deep sedation for elective outpatient procedures (noncritical care group). INTERVENTIONS: Vitamin C level was drawn for the PICU group within 24 hours of admission. Vitamin C level was drawn prior to start of deep sedation for the noncritical group. MEASUREMENT AND MAIN RESULTS: Vitamin C deficiency was present in 11/60 (18%) in the PICU group and 0/21 (0%) of the noncritical group (p < 0.05). CONCLUSIONS: Vitamin C deficiency was prevalent in our patients admitted to PICU.

Insufficient Vitamin C Levels among Adults in the United States: Results from the NHANES Surveys, 2003-2006.

Vitamin C, well-established in immune function and a key factor in epigenetic inflammatory modifications, is only obtained through consistent dietary intake. Identifying individuals at risk for Vitamin C insufficiency may guide prevention and treatment, however, national surveillance has not been evaluated in the United States since 2006. A descriptive, cross-sectional secondary analysis was performed utilizing data from the 2003-2006 National Health and Nutrition Examination Surveys (NHANES) assessing non-institutionalized adults. Five categories of plasma Vitamin C were delineated: deficiency (<11 µmol/L), hypovitaminosis (11-23 µmol/L), inadequate (23-49 µmol/L), adequate (50-69 µmol/L), and saturating (≥70 µmol/L). Results indicated 41.8% of the population possessed insufficient levels (deficiency, hypovitaminosis, and inadequate) of Vitamin C. Males, adults aged 20-59, Black and Mexican Americans, smokers, individuals with increased BMI, middle and high poverty to income ratio and food insecurity were significantly associated with insufficient Vitamin C plasma levels. Plasma Vitamin C levels reveal a large proportion of the population still at risk for inflammatory driven disease with little to no symptoms of Vitamin C hypovitaminosis. Recognition and regulation of the health impact of Vitamin C support the goal of Nutrition and Healthy Eating as part of the Healthy People 2030.

Prevalence of Hypovitaminosis C and its Relationship with Frailty in Older Hospitalised Patients: A Cross-Sectional Study.

Frailty is common in older hospitalised patients and may be associated with micronutrient malnutrition. Only limited studies have explored the relationship between frailty and vitamin C deficiency. This study investigated the prevalence of vitamin C deficiency and its association with frailty severity in patients ≥75 years admitted under a geriatric unit. Patients (n = 160) with a mean age of 84.4 ± 6.4 years were recruited and underwent frailty assessment by use of the Edmonton Frail Scale (EFS). Patients with an EFS score <10 were classified as non-frail/vulnerable/mildly frail and those with ≥10 as moderate-severely frail. Patients with vitamin C levels between 11-28 µmol/L were classified as vitamin C depleted while those with levels <11 µmol/L were classified as vitamin C deficient. A multivariate logistic regression model determined the relationship between vitamin C deficiency and frailty severity after adjustment for various co-variates. Fifty-seven (35.6%) patients were vitamin C depleted, while 42 (26.3%) had vitamin C deficiency. Vitamin C levels were significantly lower among patients who were moderate-severely frail when compared to those who were non-frail/vulnerable/mildly frail (p < 0.05). After adjusted analysis, vitamin C deficiency was 4.3-fold more likely to be associated with moderate-severe frailty (aOR 4.30, 95% CI 1.33-13.86, p = 0.015). Vitamin C deficiency is common and is associated with a greater severity of frailty in older hospitalised patients.