Vitamin D Status and Severity of Clostridium difficile Infections

Background: Clostridium difficile is the most common cause of nosocomial diarrhea, affecting up to 10% of hospitalized patients. Preliminary studies suggest an association between vitamin D status and C difficile infections (CDIs). Our goal was to investigate whether serum 25‐hydroxyvitamin D (25(OH)D) levels are associated with CDI severity. Methods: We prospectively enrolled patients diagnosed with CDI and divided them into 2 severity groups: group A (positive toxin A/B enzyme immunoassay only) and group B (positive toxin A/B enzyme immunoassay with abdominal computed tomography scan findings consistent with colitis). Serum 25(OH)D levels (25(OH)D₃, 25(OH)D₂, and total 25(OH)D) were measured on all patients after diagnosis of CDI. We performed multivariable logistic regression analyses to investigate the association between 25(OH)D levels and CDI severity, while adjusting for age, Deyo‐Charlson Comorbidity Index, recent hospitalization, and vitamin D supplementation. Results: One hundred patients were enrolled between July 2011 and February 2013. The mean (standard deviation) cohort age and Deyo‐Charlson Comorbidity Index were 62 (19) years and 4 (3), respectively; 54% of patients were male. Mean serum total 25(OH)D level was 22 (10) ng/mL. Mean 25(OH)D₃ level was significantly higher in group A (n = 71) than in group B (n = 29): 21 (1) vs 15 (2) ng/mL, respectively (P = .005). There was no observed difference in mean 25(OH)D₂ levels and total 25(OH)D levels between the 2 groups. Multivariable logistic regression analysis demonstrated an association between 25(OH)D₃ levels and CDI severity (adjusted odds ratio, 0.92; 95% confidence interval, 0.87–0.98). Conclusions: We found a significant inverse association between 25(OH)D₃ levels and CDI severity. Further studies are needed to determine whether vitamin D supplementation can improve outcomes in patients with CDI.     

25‐Hydroxyvitamin D Concentrations and Clostridium difficile Infection: A Meta‐Analysis

Background: Well‐known risk factors for Clostridium difficile infection (CDI) are exposure to antibiotics and gastric acid suppressants. Recent studies have provided some evidence of an association between hypovitaminosis D and the risk of CDI. Therefore, this meta‐analysis aimed to pool all the existing evidence to investigate the association between 25‐hydroxyvitamin D (25[OH]D) and CDI. Methods: A systematic search was conducted in 3 databases (PubMed, Embase, and Web of Sciences) for epidemiological studies that examined the association between mean 25(OH)D concentrations and CDI as well as between 25(OH)D status and CDI severity or recurrence. 25(OH)D status was defined as “lower” or “higher” at a threshold concentration of <20 or ≥20 ng/mL, respectively. Pooled effect sizes were computed using the inverse variance heterogeneity model of meta‐analysis. Results: Eight publications (n = 4479 patients) were included in the meta‐analysis. The mean concentration of 25(OH)D in patients with CDI was 3.54 ng/mL (95% confidence interval [CI], 0.39–6.89 ng/mL) lower than in patients without CDI. Patients with lower 25(OH)D status had a higher odds (odds ratio [OR], 1.61; 95% CI, 1.02–2.53) of developing severe CDI compared with those with a higher 25(OH)D status. No significant association was found between 25(OH)D status and CDI recurrence. Conclusion: The results of this meta‐analysis suggest that lower mean concentrations of 25(OH)D were associated with CDI. A lower 25(OH)D status increased the odds of severe CDI but not of CDI recurrence.     

Prevalence of vitamin D deficiency and response to oral vitamin D supplementation in patients receiving home parenteral nutrition

The purpose of this study was to document vitamin D status in home parenteral nutrition (HPN) patients and determine if oral vitamin D supplementation has a substantial effect. Methods: A retrospective chart review of eligible adults enrolled in the Southern Alberta Home Parenteral Nutrition program (n = 15) for a minimum of 6 months was conducted. Serum measurements of 25OHD were recorded and patients were categorized by vitamin D status as follows: sufficient; insufficient; deficient with respective levels of 25OHD ≥75 nmol/L, 27.5–75 nmol/L, and ≤27.5 nmol/L; and mixed. Results: Five of 15 patients had insufficient vitamin D status throughout the study period; all had short bowel syndrome. Nine were in the mixed category; 1 was consistently sufficient, and no one was consistently deficient. Patient demographics were similar between the insufficient and mixed groups. There were no significant differences in health outcomes between the insufficient and mixed vitamin D status groups. The median (interquartile range) dose and duration of vitamin D3 supplementation for the insufficient group was 5000 IU/d (4,000–7,143) for 1,175 (1,145–1,578) total days compared to 3,000 IU/d (1,000–7,143) for 1,529 (111–1,980) days for the mixed group. Conclusions: Most patients receiving HPN had insufficient vitamin D status. When prescribed high doses of oral vitamin D, patients did not consistently achieve appropriate 25OHD levels. Alternate routes of vitamin D supplementation in patients receiving HPN should be considered. Large multicenter prospective studies are needed to best characterize the relationship between vitamin D dosing for HPN patients and vitamin D status.     

Vitamin D Deficiency in Children With Intestinal Failure Receiving Home Parenteral Nutrition

Background: Vitamin D plays important roles in both skeletal and nonskeletal health. Limited data suggest that patients with intestinal failure (IF) receiving home parenteral nutrition (PN) are at risk for vitamin D deficiency due to inadequate oral intake, poor absorption, and chronic illness. The purpose of this study was to document vitamin D status in pediatric patients with IF receiving home PN. Materials and Methods: We performed a 2‐year retrospective review of children with IF followed at our center who had been on home PN for ≥6 months and had ≥1 serum 25‐hydroxyvitamin D (25‐OHD) level checked as part of routine clinical care. Patients were then categorized as deficient (<20 ng/mL), insufficient (20–29 ng/mL), or normal (≥30 ng/mL) based on their lowest vitamin D level. Demographic data and clinical characteristics were also assessed. Results: Eleven of 27 children (41%) had ≥1 insufficient 25‐OHD level, including one child with vitamin D deficiency. Diagnosis of short bowel syndrome (compared with dysmotility or malabsorption syndromes) was associated with decreased likelihood of suboptimal vitamin D status, with an odds ratio of 0.12 (95% confidence interval, 0.02–0.8, P = .028). Osteopenia was noted in 59% of the cohort. There was a trend toward higher risk for osteopenia in patients with low 25‐OHD levels compared with those with normal 25‐OHD levels (82% vs 44%, P = .109). Conclusion: Suboptimal 25‐OHD levels are common in children with IF on home PN. This emphasizes the critical importance of routine surveillance of serum vitamin D levels and consideration of enteral supplementation when indicated.     

Nutritional vitamin A status in northeast Brazilian lactating mothers

Background: Vitamin A deficiency is the major cause of morbidity and mortality among children and in women of reproductive age in developing countries. The present study aimed to assess maternal nutritional vitamin A status, as well as analyse the association of preformed vitamin A and pro‐vitamin A consumption on the nutritional status of nursing mothers, based on serum retinol and retinol colostrum concentrations coupled with dietary intake. Methods: Serum and colostrums were collected from 86 healthy parturients, recruited within 16 h postpartum. Blood samples were obtained, the morning after an overnight fast. Retinol was analysed by high‐performance liquid chromatography. Dietary vitamin A was assessed using a food frequency questionnaire and the women were separated into two groups according to the predominant dietary source of vitamin A: group A, >50% preformed vitamin A (n = 37); and group B >50% pro‐vitamin A carotenoids, (n = 49). Results: Serum retinol and total vitamin A ingestion (mean ± SD) were higher in group A than in group B (1.4 ± 0.4 μmol L^?1 and 2072.0 ± 1465.9 μg retinol activity equivalent (RAE) day^?1 versus 1.2 ± 0.6 μmol L^?1 and 1051.6 ± 920.4 μg RAE day^?1, respectively (P < 0.05), but colostrum retinol (3.4 ± 1.7 μmol L^?1 and 3.6 ± 1.9 μmol L^?1) was similar in both groups. In group B, 36.7% (n = 18) of the nursing mothers presented a risk of developing vitamin A deficiency, based on their dietary intake. Conclusions: On the basis of the intake of the pro‐vitamin A carotenoids, some women may be at risk of vitamin A deficiency. However, their status is currently normal, as indicated by serum and milk retinol concentrations.     

Vitamin D deficiency in patients receiving home parenteral nutrition

Background: In addition to its role in bone metabolism, vitamin D has important immunomodulatory and antineoplastic effects. Patients on home parenteral nutrition (HPN) receive most of their vitamin D from intravenous (IV) supplementation. Vitamin D deficiency is common in the general population, and the adequacy of vitamin D supplementation in HPN patients is unclear. The purpose of this study is to determine the vitamin D status of patients on HPN. Methods: Consecutive patients seen in a regional home nutrition program had their oral and IV vitamin D intakes determined. Plasma 25‐hydroxyvitamin D levels were measured in all patients. Intake of calcium, magnesium, and phosphate were also determined. Results: The mean 25‐hydroxyvitamin D level in 22 patients receiving HPN for a mean of 33.5 months (range, 1–177) was 42 nmol/L. Vitamin D deficiency was present in 15 (68%) patients and vitamin D insufficiency in 6 (27%) patients. The mean dietary vitamin D intake was 79.5 IU per day, while the mean IV supplementation was 166 IU per day. Conclusions: In this study of a regional Canadian HPN program, there was a high prevalence of vitamin D deficiency/insufficiency affecting virtually all patients. All patients receiving HPN should be supplemented with vitamin D and have their 25‐hydroxyvitamin D levels monitored. Further studies are required to determine optimal methods and dosing of vitamin D replacement using oral supplements or ultraviolet light therapy.     

Relationship of Vitamin D Deficiency to Clinical Outcomes in Critically Ill Patients

Background: Despite the numerous disease conditions associated with vitamin D deficiency in the general population, the relationship of this deficiency to outcome in critically ill patients remains unclear. The objective of this study is to determine the burden of vitamin D deficiency in intensive care unit (ICU) patients and determine if it is associated with poor patient outcomes. Methods: The authors conducted an analysis of samples collected from a prospective study of 196 patients admitted to a medical/surgical ICU in a tertiary care hospital. They measured serum 25‐hydroxyvitamin D at admission and up to 10 days following admission and followed patients prospectively for 28‐day outcomes. Results: Of analyzable patients, 50 (26%) were deficient (≤30 nmol/L) and 109 (56%) were insufficient (>30 and ≤60 nmol/L). Baseline 25(OH)D levels decreased significantly in all patients after 3 days in the ICU and remained significantly lower through 10 days (P < .001). 25(OH)D status was not significantly associated with 28‐day all‐cause mortality (hazard ratio [HR], 0.89; 95% confidence interval, [CI] 0.37–2.24). Higher levels of 25(OH)D were associated with a shorter time‐to‐alive ICU discharge (HR, 2.11; 95% CI, 1.27–3.51). 25(OH)D‐deficient patients showed a nonstatistically significant trend toward a higher infection rate (odds ratio [OR], 3.20; 95% CI, 0.784–13.07; P = .11) compared with patients with sufficient levels of 25(OH)D. Conclusions: This study demonstrates significant decreases in vitamin D status over the duration of the patient's ICU stay. Low levels of vitamin D are associated with longer time to ICU discharge alive and a trend toward increased risk of ICU‐acquired infection.     

Clinical Trial of Vitamin D2 vs D3 Supplementation in Critically Ill Pediatric Burn Patients

Background: Hypovitaminosis D exists postburn. However, evidence‐based guidelines for vitamin D repletion are unknown. This investigation examined differences between D₂ and D₃ supplementation on outcome in children with burn injuries. Methods: Fifty patients with total body surface area burn of 55.7% ± 2.6% and full‐thickness injury of 40.8% ± 3.8% were enrolled, ranging in age from 0.7–18.4 years. All participants received multivitamin supplementation per standardized clinical protocol. In addition, 100 IU/kg D₂, D₃, or placebo was administered daily during hospitalization using a randomized, double‐blinded study design. Assay of total 25‐hydroxyvitamin D (D25), 1,25‐dihydroxyvitamin D (D1,25), 25‐hydroxyvitamin D₂ (25‐OH‐D₂), 25‐hydroxyvitamin D₃ (25‐OH‐D₃), and parathyroid hormone (PTH) was performed at 4 preplanned time intervals (baseline, midpoint, discharge, and 1 year postburn). Differences in vitamin D status were compared over time and at each specific study interval. Results: There were no significant differences in serum vitamin D levels between groups, but >10% of patients had low D25 at discharge, and percent deficiency worsened by the 1‐year follow up for the placebo (75%), D₂ (56%), and D₃ (25%) groups. There were no statistical differences in PTH or clinical outcomes between treatment groups, although vitamin D supplementation demonstrated nonsignificant but clinically relevant decreases in exogenous insulin requirements, sepsis, and scar formation. Conclusions: The high incidence of low serum D25 levels 1 year following serious thermal injury indicates prolonged compromise. Continued treatment with vitamin D₃ beyond the acute phase postburn is recommended to counteract the trajectory of abnormal serum levels and associated morbidity.     

Low Vitamin D Status Among Obese Adolescents: Prevalence and Response to Treatment

PurposeTo explore the prevalence of low vitamin D status among obese adolescents and to examine the effect of current management of low vitamin D status in these patients.MethodsA retrospective chart review of obese adolescents who had been screened for vitamin D status by serum total 25-hydroxyvitamin D (25(OH)D) level. Vitamin D deficiency was defined as 25(OH)D level of <20 ng/mL, vitamin D insufficiency as 25(OH)D level of 20–30 ng/mL, and vitamin D sufficiency as 25(OH)D level of >30 ng/mL. Adolescents with vitamin D deficiency were treated with 50,000 IU of vitamin D once a week for 6–8 weeks, whereas adolescents with vitamin D insufficiency were treated with 800 IU of vitamin D daily for 3 months. Repeat 25(OH)D was obtained after treatment.ResultsThe prevalence rate of low vitamin D status among 68 obese adolescents (53% females, 47% males, age: 17 ± 1 years, body mass index: 38 ± 1 kg/m², Hispanic: 45%, African American: 40%, Caucasian: 15%) was 100% in females and 91% in males. Mean (±SE) 25(OH)D level was significantly higher in summer (20 ± 8 ng/mL) than in spring (14 ± 4 ng/mL, p < .02), and significantly lower in winter (15 ± 7 ng/mL) than in fall (25 ± 15 ng/mL, p < .05). Although there was a significant (p < .00001) increase in mean 25(OH)D after the initial course of treatment with vitamin D, 25(OH)D levels normalized in only 28% of the participants. Repeat courses with the same dosage in the other 72% did not significantly change their low vitamin D status.ConclusionsIncreased surveillance and possibly higher vitamin D doses are warranted for obese adolescents whose total 25(OH)D levels do not normalize after the initial course of treatment.     

Serum vitamins in adult patients with short bowel syndrome receiving intermittent parenteral nutrition

Background: Short bowel syndrome (SBS) occurs after massive intestinal resection, and parenteral nutrition (PN) therapy may be necessary even after a period of adaptation. The purpose of this study was to determine the vitamin status in adults with SBS receiving intermittent PN. Methods: The study was conducted on hospitalized adults with SBS who were receiving intermittent PN therapy (n = 8). Nine healthy volunteers, paired by age and sex, served as controls. Food ingestion, anthropometry, plasma folic acid, and vitamins B₁₂, C, A, D, E, and K were evaluated. Results: The levels of vitamins A, D, and B₁₂ in both groups were similar. SBS patients presented higher values of folic acid (21.3 ± 4.4 vs 14.4 ± 5.2, P = .01) and lower values of vitamin C (0.9 ± 0.4 vs 1.2 ± 0.3 mg/dL, P = .03), α‐tocopherol (16.3 ± 3.4 vs 24.1 ± 2.7 µmol/L, P < .001), and phylloquinone (0.6 ± 0.2 vs 1.0 ± 0.5 nmol/L, P < .03). Eight‐seven percent of patients had vitamin D deficiency, and all patients presented with serum vitamin E levels below reference values. Conclusions: Despite all efforts to offer all the nutrients mentioned above, SBS patients had lower serum levels of vitamins C, E, and K, similar to those observed in patients on home PN. These findings suggest that the administered vitamins were not sufficient for the intermittent PN scheme and that individual adjustments are needed depending on the patient's vitamin status.     

Prospective,Randomized, Double‐Blind,Parallel‐Group,Comparative Effectiveness Clinical Trial Comparing a Powder Vehicle Compound of Vitamin D With an Oil Vehicle Compound in Adults With Cystic Fibrosis

Background: There is little consensus on the most efficacious vehicle substance for vitamin D supplements. Fat malabsorption may impede the ability of patients with cystic fibrosis (CF) to absorb vitamin D in an oil vehicle. We hypothesized that vitamin D contained in a powder vehicle would be absorbed more efficiently than vitamin D contained in an oil vehicle in patients with CF. Methods: In this double‐blind, randomized controlled trial, hospitalized adults with CF were given a one‐time bolus dose of 100,000 IU of cholecalciferol (D₃) in a powder‐based or oil‐based vehicle. Serum D₃, 25‐hydroxyvitamin D, and parathyroid hormone concentrations were analyzed at 0, 12, 24, and 48 hours posttreatment. The area under the curve for serum D₃ and the 12‐hour time point were also assessed as indicators of D₃ absorption. Results: This trial was completed by 15 patients with CF. The median (interquartile range) age, body mass index, and forced expiratory volume in 1 second were 23.7 (19.9–33.2) years, 19.9 (18.6–22.6) kg/m², and 63% (37%–80%), respectively. The increase in serum D₃ and the area under the curve was greater in the powder group (P = .002 and P = .036, respectively). Serum D₃ was higher at 12 hours in the powder group compared with the oil group (P = .002), although levels were similar between groups by 48 hours. Conclusions: In adults with CF, cholecalciferol is more efficiently absorbed in a powder compared with an oil vehicle. Physicians should consider prescribing vitamin D in a powder vehicle in patients with CF to improve the absorption of vitamin D from supplements.     

Glutamine Restores Tight Junction Protein Claudin‐1 Expression in Colonic Mucosa of Patients With Diarrhea‐Predominant Irritable Bowel Syndrome

Background:Recent studies showed that patients with diarrhea‐predominant irritable bowel syndrome (IBS‐D) had an increased intestinal permeability as well as a decreased expression of tight junctions. Glutamine, the major substrate of rapidly dividing cells, is able to modulate intestinal permeability and tight junction expression in other diseases. We aimed to evaluate, ex vivo, glutamine effects on tight junction proteins, claudin‐1 and occludin, in the colonic mucosa of patients with IBS‐D. Materials and Methods: Twelve patients with IBS‐D, diagnosed with the Rome III criteria, were included (8 women/4 men, aged 40.7 ± 6.9 years). Colonic biopsy specimens were collected and immediately incubated for 18 hours in culture media with increasing concentrations of glutamine from 0.6–10 mmol/L. Claudin‐1 and occludin expression was then measured by immunoblot, and concentrations of cytokines were assessed by multiplex technology. Claudin‐1 expression was affected by glutamine (P < .05, analysis of variance). In particularly, 10 mmol/L glutamine increased claudin‐1 expression compared with 0.6 mmol/L glutamine (0.47 ± 0.04 vs 0.33 ± 0.03, P < .05). In contrast, occludin expression was not significantly modified by glutamine. Interestingly, glutamine effect was negatively correlated to claudin‐1 (Pearson r = ‐0.83, P < .001) or occludin basal expression (Pearson r = ‐0.84, P < .001), suggesting that glutamine had more marked effects when tight junction protein expression was altered. Cytokine concentrations in culture media were not modified by glutamine treatment. Conclusion: Glutamine increased claudin‐1 expression in the colonic mucosa of patients with IBS‐D. In addition, glutamine effect seems to be dependent on basal expression of tight junction proteins.     

Vitamin D status: effects on quality of life in osteoporosis among Turkish women

Background and objectives Vitamin D deficiency causes muscle weakness, impairs bone formation and neuromuscular coordination thus leading to an increase in fracture risk. It has been found that inadequate levels of vitamin D are present in most of the osteoporosis patients. However, very few studies investigate the association between vitamin D status and quality of life (QOL). The aim of this study is to investigate the effects of vitamin D on QOL among Turkish women with osteoporosis. Methods 259 patients (61.0 ± 8.9 years) with osteoporosis were evaluated by physical activity level, back pain, bone turnover markers, 25-hydroxyvitamin D [25(OH)D], parathyroid hormone levels and bone mineral density. QOL was assessed using QOL Questionnaire of the European Foundation for Osteoporosis (QUALEFFO). 25(OH)D levels below 20 ng/ml was defined as vitamin D insufficiency, below 12 ng/ml as vitamin D deficiency. Results Mean 25(OH)D level was 22.7 ± 12.6 ng/ml and mean total QUALEFFO score was 43.3 ± 14.9. Vitamin D levels were significantly correlated with all subscales and total score of QUALEFFO (r = −0.25, P = 0.0001). Vitamin D insufficiency was determined in 132 patients (51%). In vitamin D deficient (<12 ng/ml) group all subscales and total QOL were found to be poorer when compared with the groups whose vitamin D levels were ≥12 and <20 ng/ml and ≥20 ng/ml (effect sizes 0.41 and 0.62 respectively, P = 0.0001 for total QOL). Vitamin D level, education, concomitant diseases, physical activity level and pain severity were found to be significantly associated with QOL in multiple linear regression analysis model. Conclusions Vitamin D insufficiency affects physical, social and mental functions of osteoporosis patients and impairs QOL. Vitamin D was found to be one of the factors affecting QOL.     

Vitamin D deficiency in patients with inflammatory bowel disease: association with disease activity and quality of life

Background: Vitamin D deficiency is common in inflammatory bowel disease (IBD). The aim of the study was to determine the prevalence and predictors of vitamin D deficiency in an IBD cohort. It was hypothesized that vitamin D deficiency is associated with increased disease activity and lower health‐related quality of life (HRQOL). Methods: This was a retrospective cohort study. Harvey‐Bradshaw index and ulcerative colitis disease activity index were used to assess disease activity. Short Inflammatory Bowel Disease Questionnaire scores were used to assess HRQOL. Multivariate logistic regression was used to identify independent predictors of vitamin D deficiency and its association with disease activity and HRQOL. Results: The study included 504 IBD patients (403 Crohn's disease [CD] and 101 ulcerative colitis [UC]) who had a mean disease duration of 15.5 years in CD patients and 10.9 years in UC patients; 49.8% were vitamin D deficient, with 10.9% having severe deficiency. Vitamin D deficiency was associated with older age (P = .004) and older age at diagnosis (P = .03). Vitamin D deficiency was associated with lower HRQOL (regression coefficient –2.21, 95% confidence interval [CI], –4.10 to –0.33) in CD but not UC (regression coefficient 0.41, 95% CI, –2.91 to 3.73). Vitamin D deficiency was also associated with increased disease activity in CD (regression coefficient 1.07, 95% CI, 0.43 to 1.71). Conclusions: Vitamin D deficiency is common in IBD and is independently associated with lower HRQOL and greater disease activity in CD. There is a need for prospective studies to assess this correlation and examine the impact of vitamin D supplementation on disease course.     

Hypovitaminosis D: Which oral supplement therapy?

Objectives

the possible therapeutic role of vitamin D in different kind of diseases explains the growing interest in this vitamin due to its pleiotropic effects. This short report shows preliminary results of prevalence of hypovitaminosis D in a group of patients and proposes a oral supplement therapy effective in correcting hypovitaminosis in a short time, without side effects.

Methods

243 patients (aged 26–93; 67 males) were enrolled at this study. We evaluated plasma levels of 25-hydroxyvitamin D [25(OH)D] with the following cut-off values: < 10ng/ml or <0–25 nmol/L (deficient), 10–30 ng/ml or 25–75nmol/L 30–50 (insufficient) and > 30 ng/ml or > 50 nmol/L (normal). The first 73 patients with hypovitaminosis D received at baseline 25,000 IU (Cholecalciferol) per os twice a month (Tp.A). The next patients (Tp.B) at baseline received a loading dose of 50,000 IU once a week for 8 weeks, followed by a maintenance dose of 25,000 IU twice a month.

Results

hypovitaminosis D is a widespread condition (i.e. 82.3%) not only in elderly (75.6% of 75 patients aged <65 yrs and 86.5% of 168 subjects aged >65 yrs). Preliminary results at 6 months show that Tp.B is more effective in correcting hypovitaminosis D (baseline 14.4 ± 5.3 ng/ml; 24 wk 43.3 ± 14.7 ng/ml; p<0.0001).

Conclusion

hypovitaminosis D is an important public health problem. We believe it is important to quickly achieve normal Vit. D plasma values in order to produce pleiotropic effects.     

Combined selenium and vitamin C deficiency causes cell death in guinea pig skeletal muscle

Combined antioxidant deficiencies of selenium and vitamin E or vitamin E and vitamin C in guinea pigs result in clinical illness. We hypothesized that combined selenium and vitamin C deficiency would have clinical consequences because in vitro interactions of these antioxidant nutrients have been reported. Because guinea pigs are dependent on dietary vitamin C, weanling male guinea pigs were fed selenium-deficient or control diet for 15 weeks before imposing vitamin C deficiency. Four dietary groups were formed and studied 3 weeks later: controls, vitamin C deficient, selenium deficient, and doubly deficient. Deficiencies were confirmed by determinations of glutathione peroxidase activity and vitamin C concentration in liver and skeletal muscle. Plasma creatine phosphokinase activity and liver, kidney, heart, and quadriceps histopathology were determined. Doubly deficient animals had moderately severe skeletal muscle cell death as judged by histopathology and plasma creatine phosphokinase activity of 6630 ± 4400 IU/L (control, 70 ± 5; vitamin C deficient, 95 ± 110; selenium deficient, 280 ± 250). Liver, kidney, and heart histology was normal in all groups. Muscle α-tocopherol levels were not depressed in the doubly deficient group, but muscle F₂ isoprostane concentrations were elevated in them and correlated with markers of cell death. We conclude that combining selenium and vitamin C deficiencies in the guinea pig causes cell death in skeletal muscle that is more severe than the injury caused by selenium deficiency. The elevation of muscle F₂ isoprostanes is compatible with the cell death being caused by oxidative stress.     

Albumin synthesis rates are not responsive to hyperglycemic hyperinsulinemia in postoperative patients

Background: Insulin regulates albumin synthesis in vitro and in various experimental models. The current study was undertaken to determine the effects of a physiologic hyperinsulinemia on albumin synthesis in postoperative patients in whom plasma albumin concentrations are decreased. Methods: Studies were performed in postabsorptive patients after major abdominal operations. Mass spectrometry techniques were used to directly determine the incorporation rate of 1‐[¹³C]‐leucine into albumin. Consecutive blood samples were taken during a continuous isotope (D‐Glc) infusion (0.16 µmol/kg/min). Isotopic enrichments were determined at baseline (period I) and after a 4‐hour D‐glucose (D‐Glc) infusion at currently recommended rates (170 mg/kg/h, n = 10) or after infusion of saline (control group, n = 8) (period II). Results: After D‐Glc infusion, plasma insulin concentrations increased significantly (period I, 6.6 ± 1.8 µU/mL; period II, 21.4 ± 2.1 µU/mL; P < .01). In contrast, plasma insulin concentration remained constant in control patients (period I, 3.8 ± 0.9 µU/mL^?1; period II, 5.9 ± 1.1 µU/mL; not significant vs period I, but P < .005 vs the corresponding value at the end of period II in the control group). Hyperinsulinemia was without effect on fractional albumin synthesis (period I, 12.8% ± 1.9%/d; period II, 11.9% ± 1.9%/d; not significant), and synthesis rates corresponded to those measured in controls (period I, 13.0% ± 1.2%/d; period II, 12.1% ± 0.1%/d; not significant vs period I and vs D‐Glc infusion). Conclusions: A standard D‐Glc infusion is insufficient to increase albumin synthesis in postoperative patients.     

Vitamin D Deficiency Is Widespread in Cancer Patients and Correlates With Advanced Stage Disease: A Community Oncology Experience

The purpose of this study was to correlate serum vitamin D levels with potential clinical variables and to determine the extent of vitamin D deficiency in a large, outpatient oncology practice. One hundred ninety-five consecutive patients referred for consultation at a community radiation oncology center from October 8, 2008 to March 17, 2010 had vitamin D levels ordered. Patients who were deficient in vitamin D were treated with replacement therapy. Demographic and medical data were collected prospectively and subsequently analyzed. Pretreatment baseline patient and tumor characteristics were evaluated with respect to vitamin D concentrations. One hundred and sixty patients were analyzed. A total of 74% of patients had 25-hydroxyvitamin D concentrations considered either deficient (<20 ng/mL) or suboptimal (20–30 ng/mL). Replacement therapy raised serum vitamin D levels by an average of 15 ng/mL (95% CI = 11–18, P < 0.01). Lower than median serum vitamin D levels were associated with stage III disease in univariate analysis [OR = 2.6 (95% CI = 1.1–6.2), p = 0.04] as well as multivariate analysis adjusted for age, sex, body mass index, and season of draw [OR = 3.3 (95% CI = 1.1–9.7), P = 0.03]. Three-quarters of patients in our series had suboptimal or deficient circulating concentrations of 25-hydroxyvitamin D. Low serum vitamin D levels, independent of age, sex, and body mass index, predicted advanced stage disease.     

Vitamin B12 status,dietary protein intake and proton pump inhibitor use in geriatric rehabilitation subjects

Aim: To compare the dietary intake and nutritional status of users and non‐users of proton pump inhibitor medications. Methods: Cross‐sectional study of subacute rehabilitation inpatients. Forty‐nine patients (nine men and 40 women) without dementia fulfilled the study criteria. Information was collected on admission and included medical history, duration of proton pump inhibitor medication use, nutritional status and cognitive scores. Dietary data were collected by food frequency questionnaire and blood samples were analysed for vitamin B₁₂, homocysteine and methylmalonic acid concentrations. Results: Age was 80.4 ± 7.7 (mean ± SD) years and body mass index was 26 ± 6.7 kg/m². Twenty‐one (of 49) subjects had subclinical vitamin B₁₂ deficiency, which was defined as serum vitamin B₁₂ <148 pmol/L or 148–258 pmol/L and methylmalonic acid >0.30 µmol/L or tHcy >13 µmol/L (women) and >15 µmol/L (men). Subjects were stratified according to proton pump inhibitor use and vitamin B₁₂ status. The presence of subclinical deficiency was similar between the groups (χ²‐test P= 0.17). Proton pump inhibitor users had higher dietary protein and calcium intakes (but not supplement calcium intakes) compared with non‐users (93 vs 81 g/day, P= 0.002 and 968 vs 742 mg/day, P= 0.038, respectively). Conclusions: Subjects using proton pump inhibitor medications did not have lower vitamin B₁₂ status, but had higher dietary protein intakes suggesting higher intakes of meats, eggs and dairy foods may reduce the risk of developing vitamin B₁₂ deficiency whilst taking proton pump inhibitor medications.     

Estimation of total body water from bioelectrical impedance spectroscopy in oncology outpatients receiving radiotherapy and agreement with three prediction equations

Background: Bioelectrical impedance spectroscopy (BIS) may be more accurate in determining total body water (TBW) than bioelectrical impedance analysis (BIA). The present study compared the agreement between three TBW prediction equations developed using BIA and BIS‐derived TBW in oncology outpatients. Methods: A cross‐sectional, observational study was conducted in 37 outpatients receiving radiotherapy (27 males/10 females, aged 68.3 ± 10.2 years). TBW was estimated by BIS (TBW_BIS) and three BIA TBW prediction equations (TBW_ca‐u: underweight cancer patients; TBW_ca‐n: normal‐weight cancer patients; and TBW_rad: patients receiving radiotherapy). Bland–Altman analyses determined agreement between methods. BIS‐derived TBW using new resistivity constants was calculated. Results: The mean ± SD of TBW estimated by BIS was 39.8 ± 8.3 L, which was significantly different from the prediction equations; TBW_rad 35.1 ± 7.9 L, TBW_ca‐u 33.1 ± 7.5 L and TBW_ca‐n 32.3 ± 7.3 L, (P < 0.001). Using new resistivity constants, TBW was 36.2 ± 8.1 L but this still differed from the equations (P < 0.001). Bias between TBW_BIS and that predicted by the equations was in the range 4.7–7.4 L or 1.1–3.9 L using new resistivity constants. Conclusions: TBW estimated by BIS cannot be directly compared with oncology‐specific BIA equations, suggesting that BIS cannot be used at the group level in outpatients receiving radiotherapy. There was a reduced bias with BIS using new resistivity constants; however, further research should determine any advantage of BIS over BIA in this population.