Nitric Oxide Production and Effects in Group B Streptococcus Chorioamnionitis.

Intrauterine infection, or chorioamnionitis, due to group B Streptococcus (GBS) is a common cause of miscarriage and preterm birth. To cause chorioamnionitis, GBS must bypass maternal-fetal innate immune defenses including nitric oxide (NO), a microbicidal gas produced by nitric oxide synthases (NOS). This study examined placental NO production and its role in host-pathogen interactions in GBS chorioamnionitis. In a murine model of ascending GBS chorioamnionitis, placental NOS isoform expression quantified by RT-qPCR revealed a four-fold expression increase in inducible NOS, no significant change in expression of endothelial NOS, and decreased expression of neuronal NOS. These NOS expression results were recapitulated ex vivo in freshly collected human placental samples that were co-incubated with GBS. Immunohistochemistry of wild type C57BL/6 murine placentas with GBS chorioamnionitis demonstrated diffuse inducible NOS expression with high-expression foci in the junctional zone and areas of abscess. Pregnancy outcomes between wild type and inducible NOS-deficient mice did not differ significantly although wild type dams had a trend toward more frequent preterm delivery. We also identified possible molecular mechanisms that GBS uses to survive in a NO-rich environment. In vitro exposure of GBS to NO resulted in dose-dependent growth inhibition that varied by serovar. RNA-seq on two GBS strains with distinct NO resistance phenotypes revealed that both GBS strains shared several detoxification pathways that were differentially expressed during NO exposure. These results demonstrate that the placental immune response to GBS chorioamnionitis includes induced NO production and indicate that GBS activates conserved stress pathways in response to NO exposure.

Liver Microabscesses in a Premature Neonate With Eosinophilic Colitis.

Hepatic abscesses in premature infants are rare with less than 100 case reports documented in literature. We report a case of a premature infant diagnosed with hepatic microabscesses secondary to eosinophilic colitis. A 33 4/7-week preterm female neonate presented with bilious emesis, abdominal distention, and severe hematochezia. Eosinophilic enterocolitis was suspected. Hypoechoic regions in the anterior liver identified on computed tomography were considered liver microabscesses. This unique case exemplifies how prematurity increases the risk of mucosal damage in the presence of eosinophilic colitis causing enteric bacteria to seed into the liver through the portal vein, resulting in hepatic microabscesses.

Reduced Dose of Beta-Alanine Is Sufficient to Maintain Performance in Repeated Sprints.

ABSTRACT: Zandona, BA, Ramos, RA, de Oliveira, CdS, McAnulty, SR, Ferreira, LHB, Smolarek, AC, Enes, AAN, Urbinati, KMdSS, Aragon, AA, Schoenfeld, BJ, and de Souza Junior, TP. Reduced Dose of Beta-Alanine Is Sufficient to Maintain Performance in Repeated Sprints. J Strength Cond Res 36(6): 1636-1642, 2022-Beta-alanine (BA) supplementation has been shown to be effective in improving physical performance by increasing carnosine concentration. However, it is still necessary to know the effect of a maintenance dose on performance. Thus, this study aimed to investigate the effects of a maintenance dose of BA supplementation on performance. Forty-four anaerobically trained men with 23.9 ± 3.8 years of age, 176.0 ± 0.05 cm height, 81.2 ± 7.5 kg body mass, and 15.5 ± 2.9% of body fat performed a cycle ergometer test consisting of 4 sprints of 30 s with 4 minutes of active recovery. The study comprised 3 phases: (a) presupplementation, (b) supplementation with 6.4 g·d-1 BA or placebo, and (c) postsupplementation with a maintenance dose of 1.2 g·d-1 of BA or interruption of supplementation. Data were analyzed using generalized estimated equations with a priori 0.05 level of significance. The placebo group and interruption group presented a lower power (7.28 ± 0.66 and 7.71 ± 0.42 W·kg-1 vs. 8.04 ± 0.84 and 9.25 ± 1.18 W·kg-1, respectively; p < 0.05) during the third sprint in postsupplementation, whereas the maintenance group maintained the required power (7.47 ± 1.03 vs. 8.74 ± 1.07 W·kg-1; p > 0.05). The placebo group also presented higher percentage of fatigue (44.5% ± 12.3 and 44.8% ± 7.7 vs. 37.6 ± 7.2%; p = 0.021) and higher subjective perception of exertion (8.92 ± 0.90 vs. 8.00 ± 1.60; p = 0.028). Therefore, the maintenance dose of 1.2 g·d-1 BA was effective in maintaining performance, whereas a reduction in performance was observed after supplementation interruption.

Interpreter Use for Limited English Proficiency Patients/Families: A QI Study.

BACKGROUND: Communication is fundamental to high-quality health care. Despite federal requirements to provide interpreters and growing evidence favoring the benefits of interpreter use, providers' use of interpreters remains suboptimal. In acute care settings, where decisions need to be made rapidly on the basis of changing clinical circumstances, this has proven to be challenging. METHODS: We designed a quality improvement project using the model for improvement methodology for patients admitted to the pediatric hospital medicine service. A multidisciplinary team developed interventions focused on provider education and leveraging health information technology (IT). We used health IT to improve the identification of families with limited English proficiency, improve access to various modalities of interpreting, standardize workflow to request face-to-face (F2F) interpreters, and create a designated place in the electronic health record for interpreter use documentation. The use of all forms (telephone, video, and F2F) of interpreter service, documentation of interpreter uses, and F2F interpreter overload were tracked monthly for 3 years. RESULTS: The baseline use of interpreter services for the pediatric hospital medicine inpatient service was 64%. After starting the project, the use of interpreter service increased to 97% and has sustained for more than a year since the project's completion. The use of F2F interpreters also increased from a baseline of 20% to 54% post intervention. CONCLUSIONS: We successfully achieved and sustained our goals of improving interpreter use through supportive leadership and a multidisciplinary approach using quality improvement methodology. Future efforts should be focused on defining and standardizing metrics for families with limited English proficiency across institutions and using health IT to improve care.

Genome-Wide fitness analysis of group B Streptococcus in human amniotic fluid reveals a transcription factor that controls multiple virulence traits.

Streptococcus agalactiae (group B Streptococcus; GBS) remains a dominant cause of serious neonatal infections. One aspect of GBS that renders it particularly virulent during the perinatal period is its ability to invade the chorioamniotic membranes and persist in amniotic fluid, which is nutritionally deplete and rich in fetal immunologic factors such as antimicrobial peptides. We used next-generation sequencing of transposon-genome junctions (Tn-seq) to identify five GBS genes that promote survival in the presence of human amniotic fluid. We confirmed our Tn-seq findings using a novel CRISPR inhibition (CRISPRi) gene expression knockdown system. This analysis showed that one gene, which encodes a GntR-class transcription factor that we named MrvR, conferred a significant fitness benefit to GBS in amniotic fluid. We generated an isogenic targeted deletion of the mrvR gene, which had a growth defect in amniotic fluid relative to the wild type parent strain. The mrvR deletion strain also showed a significant biofilm defect in vitro. Subsequent in vivo studies showed that while the mutant was able to cause persistent murine vaginal colonization, pregnant mice colonized with the mrvR deletion strain did not develop preterm labor despite consistent GBS invasion of the uterus and the fetoplacental units. In contrast, pregnant mice colonized with wild type GBS consistently deliver prematurely. In a sepsis model the mrvR deletion strain showed significantly decreased lethality. In order to better understand the mechanism by which this newly identified transcription factor controls GBS virulence, we performed RNA-seq on wild type and mrvR deletion GBS strains, which revealed that the transcription factor affects expression of a wide range of genes across the GBS chromosome. Nucleotide biosynthesis and salvage pathways were highly represented among the set of differentially expressed genes, suggesting that MrvR may be involved in regulating nucleotide availability.

Evaluation of Nutritional, Inflammatory, and Fatty Acid Status in Patients with Gastric and Colorectal Cancer Receiving Chemotherapy.

Malnutrition is prevalent in gastrointestinal (GI) cancer patients, possibly due to inflammation and altered fatty acids (FA). There is a lack of research describing nutritional decline in these patients during chemotherapy. We described changes in nutritional, inflammatory, and FA status over time and factors relating to change in nutritional status according to tumor presence in 41 GI cancer patients undergoing first-line treatment over four chemotherapy visits, using linear mixed effects models. At baseline, 53% of patients were malnourished. Over time, there was a decrease in the proportion of malnourished vs. well-nourished individuals (ß= -0.564, p < 0.01). Median concentrations of plasma linoleic acid, arachidonic acid, eicosapentaenoic acid, docosahexaenoic acid, total n-3, total n-6 and total plasma phospholipid FA increased over time. Changes over time in nutritional status based on weight (p < 0.001), fat free mass (FFM) measured by bioelectrical impedance analysis (BIA, p = 0.02), and skinfold anthropometry (FSA, p = 0.04) were significantly dependent on tumor presence. There were positive associations between weight and total n-3 (ß = 0.02, p < 0.01), FFM and IL-6 (BIA, ß = 0.028, p = 0.02; FSA, ß = 0.03, p = 0.02), and FFM and total n-6 (BIA, ß = 0.003, p = 0.01). Changes in nutritional status during chemotherapy were negatively impacted by tumor presence, and were associated with increasing concentrations of cytokines and FA.

Thiamin supplementation does not improve left ventricular ejection fraction in ambulatory heart failure patients: a randomized controlled trial.

BACKGROUND: Thiamin, a water-soluble B-complex vitamin, functions as a coenzyme in macronutrient oxidation and in the production of cellular ATP. Data suggest that thiamin depletion occurs in heart failure (HF). Therefore, thiamin supplementation in HF patients may improve cardiac function. OBJECTIVE: We sought to determine whether oral thiamin supplementation improves left ventricular ejection fraction (LVEF), exercise tolerance, and quality of life among patients with HF and reduced LVEF. METHODS: In this prospective, multicenter, double-blind, placebo-controlled randomized trial, eligible ambulatory patients with HF and reduced LVEF were recruited from 4 academic and community hospitals between 2010 and 2015. Participants were randomly assigned to receive either 200 mg oral thiamin mononitrate per day or placebo for 6 mo. RESULTS: Sixty-nine patients (mean ± SD age: 64 ± 12 y; 83% men; LVEF: 37% ± 11%) were randomly assigned: 34 received placebo and 35 received thiamin supplementation. Erythrocyte thiamin pyrophosphate and urine thiamin concentrations were significantly higher in the supplemented group than in the placebo group at 6 mo (P = 0.02 and <0.001, respectively). At 6 mo, LVEF was significantly higher in the placebo group than in the thiamin group (38%; 95% CI: 36%, 39% compared with 35%; 95% CI: 33%, 37%, P = 0.047) after adjusting for baseline measurements. There were no significant differences in Minnesota Living with Heart Failure score, distance walked in 6 min, and N-terminal prohormone of brain natriuretic peptide concentrations between the 2 groups. One patient (2.9%) in the thiamin-supplemented group and none in the control group died at 6 mo. CONCLUSIONS: In ambulatory patients with HF and reduced LVEF, thiamin supplementation for 6 mo did not improve LVEF, quality of life, or exercise capacity, despite increases in thiamin concentrations. These findings do not support routine thiamin supplementation in the treatment of HF and reduced LVEF.This trial was registered at clinicaltrials.gov as NCT00959075.

Prevalence of Thiamin Deficiency in Ambulatory Patients with Heart Failure.

BACKGROUND: Thiamin is a required coenzyme in energy production reactions that fuel myocardial contraction. Therefore, thiamin deficiency (TD) may aggravate cardiac dysfunction in patients with systolic heart failure (HF). OBJECTIVE: To determine the prevalence of TD in ambulatory participants with HF as well as the relationships between thiamin status and HF severity, dietary thiamin intake, diuretic use, and circulating neurohormones. DESIGN: A cross-sectional study comparing the prevalence of TD in ambulatory patients with HF with that of controls. Demographic, anthropometric, nutrition, medication use, and heart function data were collected from direct interviewing, questionnaires, and medical records. Blood samples were obtained to measure levels of neurohormones and assess TD. PARTICIPANTS/SETTING: Fifty age-matched control participants without HF and 100 outpatients with HF and reduced left ventricular function were recruited from clinics at St Michael's Hospital, University Health Network and Mount Sinai Hospital, Toronto, Ontario, Canada, between September 2009 and February 2011. MAIN OUTCOME MEASURES: To assess TD, erythrocyte thiamin pyrophosphate (TPP) was measured using high-performance liquid chromatography. TD was defined as TPP<6.07 µg/dL (180 nmol/L). STATISTICAL ANALYSES PERFORMED: Prevalence rates were analyzed using χ2 test. Nonparametric statistics (Jonckheere-Terpstra, Kruskal-Wallis, Spearman's correlation) were used to assess TPP levels in relation to HF severity, medication use and plasma concentrations of F2-isoprostanes, norepinephrine, and N-terminal pro-brain natriuretic peptide (NT-proBNP). RESULTS: There was no significant difference in the prevalence of TD in outpatients with HF (6%) and controls (6%) (P=0.99). No relationship was found between heart function, thiamin intake, use or dose of diuretics, and TD. A positive relationship was observed between erythrocyte TPP and F2-isoprostane levels (rs=0.22, P=0.03) but not between erythrocyte TPP and norepinephrine (P=0.45) and NT-proBNP (P=0.58). CONCLUSION: The prevalence of TD was low in ambulatory HF participants suggesting that, unlike hospitalized patients, ambulatory patients may be at a low risk for TD.

A modified portfolio diet complements medical management to reduce cardiovascular risk factors in diabetic patients with coronary artery disease.

BACKGROUND & AIMS: Secondary prevention can improve outcomes in high risk patients. This study investigated the magnitude of cardiovascular risk reduction associated with consumption of a modified portfolio diet in parallel with medical management. DESIGN: 30 patients with type II diabetes, 6 weeks post bypass surgery received dietary counseling on a Modified Portfolio Diet (MPD) (low fat, 8 g/1000 kcal viscous fibres, 17 g/1000 kcal soy protein and 22 g/1000 kcal almonds). Lipid profiles, endothelial function and markers of glycemic control, oxidative stress and inflammation were measured at baseline and following two and four weeks of intervention. Seven patients with no diet therapy served as time controls. RESULTS: Consumption of the MPD resulted in a 19% relative reduction in LDL (1.9 ± 0.8 vs 1.6 ± 0.6 mmol/L, p < 0.001) with no change in HDL cholesterol. Homocysteine levels dropped significantly (10.1 ± 2.7 vs 7.9 ± 4 µmol/L, p = 0.006) over the study period. Flow mediated dilatation increased significantly in treated patients (3.8 ± 3.8% to 6.5 ± 3.6%, p = 0.004) while remaining constant in controls (p = 0.6). Endothelial progenitor cells numbers (CD34+, CD 133+ and UEA-1+) increased significantly following MPD consumption (p < 0.02) with no difference in migratory capacity. In contrast, time controls showed no significant changes. CONCLUSION: Dietary intervention in medically managed, high risk patients resulted in important reductions in risk factors. Clinical Trials registry number NCT00462436.

Thiamin deficiency and heart failure: the current knowledge and gaps in literature.

The management of heart failure (HF) represents a significant challenge for both patients as well as the healthcare system in industrialized countries. Thiamin is a required coenzyme in the energy-producing reactions that fuel myocardial contraction. Therefore, thiamin deficiency (TD) may contribute to myocardial weakness by limiting the energy available for contraction. Previous studies have reported a wide range in the prevalence of TD in patients with HF (3-91 %). The impact of thiamin supplementation in patients with HF is inconclusive. Studies conducted to date are limited by their small sample size, indirect methods of assessing thiamin concentration, methodological inconsistencies, use of impractical means of thiamin supplementation, a focus on hospitalized patients, and lack a robust technique for the assessment of cardiac function. Future large prospective studies and randomized controlled trials are needed to improve our understanding of any change in nutritional requirements associated with chronic disease as well as the clinical benefit of supplementation.

Reflections on Perceived Preparedness of Dietetic Internship Graduates Following Entry into Practice.

PURPOSE: To report on the perceived level of preparedness of dietetic internship (DI) graduates for entrance into practice as dietitians. METHODS: Graduates of an Ontario based, nonintegrated DI program from 2007-2011 who were at least 1 year postgraduation were surveyed to determine their level of perceived preparedness for practice using an electronic, content validated, self-administered questionnaire. RESULTS: Of 38 eligible graduates, 23 (61%) responded. Seventy-five percent of respondents were working as clinical dietitians, and 30% were working as community dietitians. Eighty-five percent of graduates reported feeling well or very well prepared for practice. Clinical and professional practice tasks were scored highest in terms of preparedness (ratings above 4.5/5) and research-related tasks such as using the research literature (4.1/5), making evidence-based decisions (4.2/5), and engaging in practice-based research (4.1/5) scored lower. Training gaps identified by 32% of respondents included community nutrition and management skill training. CONCLUSIONS: Overall, results indicate that this DI program provides a positive training experience that prepares its graduates for entrance into practice as dietitians. Qualitative comments identifying gaps and improvements have guided changes to the curriculum including strengthening community-based placements. Post-graduate surveys represent an important tool in assuring that training programs evolve to meet the needs of students entering the workforce.

Preoperative carbohydrate loading in patients undergoing coronary artery bypass or spinal surgery.

BACKGROUND: Surgical stress creates a state of insulin resistance which may contribute to the development of hyperglycemia and, subsequently, postoperative complications. Consumption of an oral carbohydrate supplement before surgery may improve insulin sensitivity and reduce hyperglycemia. In this trial, we investigated the effects of carbohydrate supplementation on insulin resistance in coronary artery bypass graft and spinal decompression and fusion surgical patients. METHODS: Twenty-six patients undergoing coronary artery bypass graft and 12 undergoing spine surgery were randomized to receive 800 mL of an oral carbohydrate supplement the evening before and 400 mL 2 hours before surgery (CHO) or to fasting per standard hospital protocol (FAST). Baseline and postoperative measurements of insulin sensitivity were assessed using the short insulin tolerance test and homeostasis model assessment (HOMA). Interleukin-6, C-reactive protein, and free fatty acid levels were determined at baseline, postoperatively, and 24, 48, and 72 hours after surgery. Adiponectin was measured at baseline. Subjective feelings of well-being were measured immediately before surgery, and intra- and postoperative outcomes were documented. RESULTS: Postoperative insulin sensitivity did not differ significantly between the FAST and CHO groups whether measured by the short insulin tolerance test (rate of disappearance of blood glucose: 0.29%/min vs 0.38%/min; 99% confidence interval [CI] for difference, -0.17 to 0.32, P = 0.41) or HOMA (insulin resistance at values >1: 2.3 vs 3.3; 99% CI for difference, -0.8 to 2.8, P = 0.14). Circulating blood glucose levels after surgery in the CHO group, 6.2 mmol/L, tended to be lower than the FAST group, 6.9 mmol/L (99% CI for difference, -1.7 to 0.25, P = 0.05) and postoperative ß-cell function, measured by HOMA-ß (impaired ß-cell function at values <100%), tended to be higher in the CHO group, 87%, vs 47.5% in the FAST group (99% CI for difference, -9.4 to 88.4), but these differences were not significant. Adiponectin levels were not different between groups at baseline, and levels of free fatty acid, interleukin-6 and C-reactive protein were not affected by treatment. CONCLUSIONS: Preoperative carbohydrate loading did not improve postoperative insulin sensitivity. However, the observed postoperative blood glucose levels and ß-cell function as well as secondary outcomes warrant further study to reevaluate traditional fasting practices in surgical patients.

Diet order entry by registered dietitians results in a reduction in error rates and time delays compared with other health professionals.

In January 2009, registered dietitians (RDs) at St Michael's Hospital (Toronto, Ontario, Canada) were granted approval for nonmedication order entry of physician-approved nutrition-related orders for the patients to whom RDs provided care. The aim of this project was to document any changes in the numbers and types of diet order errors and time delays that were associated with this policy change. A retrospective chart audit was conducted to document the error rate in 672 nutrition-related orders placed before, and in 633 orders placed after, implementation of RD diet order entry on high-risk inpatient units. Error rates for all nutrition-related orders decreased by 15% after RD order entry access (P<0.01). Error rates for diet orders entered by RDs were significantly lower in comparison with those entered by clerical assistants or registered nurses (P<0.001). Time delays for orders electronically entered were reduced by 39% (from 9.1 to 5.7 hours; P<0.01). Allowing RDs access to the electronic order entry system has improved overall timeliness of nonmedication order entries and improved patient safety by decreasing error rates in diet orders. This study supports this institutional policy change and provides evidence that RDs have the knowledge and skills to accurately process nonmedication order entries for the patients they have assessed. Finally, the current findings support the need for ongoing education and training of all health professionals in nonmedication order entry to reduce errors and improve safety.

The role of B vitamins in the management of heart failure.

Heart failure (HF) is the leading cause of morbidity and mortality in industrialized countries, creating a significant burden on both the healthcare system and quality of life. Research efforts continue to explore new pharmaceutical or surgically based approaches to HF management, but the role of nutrition as an adjunct therapy has been largely ignored. Elderly age, anorexia, malabsorption, premature satiety, and disease severity are among the factors identified as contributing to reduced nutrient intakes in patients with HF. These factors suggest that patients with HF are at increased risk of multiple-nutrient deficiencies, including B vitamins. B vitamins may be of particular therapeutic interest because of their key roles as cofactors in energy-producing pathways. Recently, impaired stores of high-energy compounds have been linked with myocardial dysfunction and prognosis in patients with HF. Therefore, deficiencies of B vitamins might contribute to reduced energy stores and disease progression. This review summarizes the existing literature both with respect to the prevalence of B vitamin deficiency as well as evidence from supplementation trials in patients with HF. The findings suggest that most of the literature in this area has focused on thiamin deficiency in patients with HF, whereas other B vitamins remain largely unstudied. Although few sporadic trials suggest a role for B vitamins in the management of HF, none are conclusive. Therefore, there is a need for larger, more robust trials to assist in defining the B vitamin requirements as well as the impact of supplementation on both morbidity and mortality in patients with HF.

Evaluation of taste sensitivity in patients undergoing coronary artery bypass graft surgery.

Patients report changes in their perception of food tastes following cardiac surgery. This study was designed to explore changes in taste sensitivity following coronary artery bypass graft (CABG) surgery. Detection and recognition thresholds for sweet (sucrose), salty (sodium chloride), sour (citric acid), and bitter (quinine hydrochloride) were determined using the multiple forced-choice ascending concentration series method at baseline (presurgical), discharge, 5 weeks, and 16 weeks post-CABG. Demographic and gastrointestinal data were also obtained. Mixed-model analyses for repeated measures were performed using the baseline scores as reference. Thirty-three patients (mean age=61.8+/-8 years), consented to participate in the study between January 2003 and January 2006, with 13 completing all visits. Detection and recognition thresholds for sweet were significantly lower at discharge compared with baseline (1.7+/-1.2 vs 2.43+/-1.4 and 5.1+/-1.8 vs 5.5+/-1.3, respectively; P<0.05). This difference remained significant 4 months after surgery. Detection and recognition thresholds for salt also declined with time, with significant differences at 4 months post-surgery (2.3+/-2.0 vs 1.8+/-1.5; P<0.001 and 5.3+/-1.3 vs 4.2+/-2.2; P<0.05, respectively). The same trends were noted for the detection of sour and the recognition of bitter. Patients undergoing CABG demonstrated stable or improved taste sensitivity during the recovery period. Further studies aimed at clarifying the relationships between the biological state, taste sensitivity, reported taste changes, and food intake will help to clarify the clinical impact of taste changes and subsequently to guide clinical nutrition care.

B-vitamin deficiency in hospitalized patients with heart failure.

The impact of heart failure and its treatment on specific nutrient requirements is unknown. Furthermore, depletion of water-soluble B vitamins that play key roles in the production of cellular energy in patients with heart failure can contribute to depletion of energy reserves observed in the failing heart. A cross-sectional study recently reported that approximately one third of hospitalized patients with heart failure had tissue levels suggestive of thiamin deficiency (vitamin B-1). Riboflavin (vitamin B-2) and pyridoxine (vitamin B-6) are similar to thiamin in that they are water-soluble, subject to renal excretion, have limited tissue storage, and are dependent on intake. Therefore, it was hypothesized that the status of these B vitamins may also be adversely affected by heart failure. As a result, the prevalence of patients at risk of vitamin B-2 (erythrocyte glutathione reductase activity coefficient > or = 1.2) and B-6 deficiency (plasma B-6 < or = 20 nmol/L) was determined in a cross-section of 100 patients hospitalized with heart failure between April 2001 and June 2002 as well as in a group of volunteers without heart failure. Twenty-seven percent of patients with heart failure had biochemical evidence of vitamin B-2 deficiency, while 38% had evidence of B-6 deficiency. These prevalence rates were significantly higher than those observed in the volunteers without heart failure (2% and 19%, respectively; P < or = 0.02). Use of common B-vitamin-containing supplements by patients with heart failure did not significantly reduce deficiency rates in comparison with those who did not use supplements (B-2 P=0.38 or B-6 P=0.18)). Finally, while 80% of patients with heart failure took diuretics, neither the dose nor the duration of furosemide use was related to the presence of either B-2 or B-6 deficiency. Given the physiologic importance of these vitamins, further investigations aimed at determining the effect of heart failure on specific nutrient requirements as well as the safety and efficacy of B-vitamin supplementation are warranted.

Pre-operative modification of dietary glycemic index improves pre but not post-operative indices of insulin resistance in patients undergoing coronary artery bypass graft surgery.

BACKGROUND: Improving insulin sensitivity in coronary artery bypass grafting (CABG) patients may translate into improved glycemic control and postoperative outcomes. The implementation of a low glycemic index (LGI) diet in the pre-operative period may improve insulin sensitivity and subsequently impact on the development of post-operative insulin resistance. The aim of this study was to determine whether a short term LGI diet would reduce postoperative insulin resistance. METHODS: Eleven non-diabetic patients referred for elective CABG surgery were randomized to consume either a high glycemic index (HGI)(5) or LGI (6) diet for three weeks prior to their surgery. Outcomes, including insulin sensitivity (SITT, HOMA), were measured at baseline, preoperatively and postoperatively. RESULTS: Substitution of HGI or LGI foods resulted in an average 8.6 unit increase, or 11.0 unit decrease, respectively, in glycemic index. Insulin sensitivity (HOMA) improved significantly in the LGI group preoperatively compared to the HGI group (p = 0.018). Insulin sensitivity (SITT) was significantly reduced postoperatively in both groups, but no significant difference was found between groups. There was a trend in the LGI group towards improved glycemic control which warrants further investigation. CONCLUSION: A preoperative LGI diet presents a non-invasive cardio-protective opportunity warranting clinical trial.

Triple nutrient supplementation improves survival, infarct size and cardiac function following myocardial infarction in rats.

BACKGROUND AND AIM: We evaluated the impact of triple nutrient supplementation (TNS: carnitine, taurine and coenzyme Q(10)) vs. carnitine alone (CARN) or placebo on survival, infarct size, cardiac function and metabolic gene expression using a model of myocardial infarction (MI) in rats. METHODS AND RESULTS: Male Wistar rats were randomized to three groups divided in two independent studies prior to ligation of the left anterior descending coronary artery (LAD): TNS vs. Placebo and TNS vs. CARN. Nutrient supplementation [L-carnitine (300 mg/day), coenzyme Q(10) (15 mg/kg body weight/day) and taurine (0.1M)] was administered daily for four weeks prior to and for 10 days after MI. At that time, cardiac function and infarct size were measured. Metabolic gene (mRNA) expression in the peri-infarct tissue of left ventricle from TNS, placebo or corresponding time-control rats (TNS or placebo without LAD ligation) was measured 10 days after MI. When compared to placebo, TNS significantly improved survival (60% vs. 34%, p<0.02), cardiac function, and reduced infarct size (30+/-7% vs. 42+/-9%, p<0.001). Although CARN improved survival like TNS (45% vs. 50%, not significant), it did not reduce infarct size (32+/-14% vs. 19+/-10%, p<0.05) or delay myocardial remodeling. In the placebo group, MI was associated with a significantly altered pattern of metabolic gene expression (glucose transporter 1, liver carnitine palmitoyl transferase 1, medium-chain acyl-CoA dehydrogenase; p<0.01 for all three) in the left ventricle peri-infarct tissue. In contrast, gene expression was normalized in the group receiving TNS. CONCLUSIONS: Our results support the potential cardioprotective impact of TNS during myocardial ischemia. In contrast to carnitine supplementation alone, TNS improved survival as well as cardiac function, gene expression and delayed remodeling.

Factors influencing patient knowledge of warfarin therapy after mechanical heart valve replacement.

BACKGROUND AND RESEARCH OBJECTIVE: Patients with mechanical heart valves must follow lifelong warfarin therapy. Warfarin, however, is a difficult drug to manage because it has a narrow therapeutic window and potentially serious side effects. Successful anticoagulation treatment is dependent upon the patient's knowledge of this drug; however, little is known regarding the determinants of such knowledge. Therefore, the purpose of this study was to determine the influence of both in-hospital teaching practices as well as socioeconomic status and demographic variables on patients' knowledge of warfarin therapy. SUBJECTS AND METHODS: A telephone survey was conducted among 100 patients 3 to 6 months after mechanical heart valve replacement. A previously validated 20-item questionnaire was used to measure the patient's knowledge of warfarin, its side effects, and vitamin K food sources. Demographic information, socioeconomic status data, and medical education information were also collected. Knowledge scores were compared using the Student t test or one-way analysis of variance. Variables with P < or = .2 on univariate analysis were entered in multiple stepwise regression analysis. RESULTS AND CONCLUSIONS: Sixty-one percent of participants had scores indicative of insufficient knowledge of warfarin therapy (score < or = 80%). Age was negatively related to warfarin knowledge scores (r = 0.27, P = .007). Patients with family incomes greater than $25,000, who had greater than a grade 8 education, and who were employed or self-employed had significantly higher warfarin knowledge scores (P = .007, P = .002, and P = .001, respectively). Gender, ethnicity, and warfarin therapy before surgery were not related to warfarin knowledge scores. Furthermore, none of the in-hospital teaching practices significantly influenced knowledge scores, whereas receiving postdischarge community counseling significantly improved knowledge scores (P = .001). Multivariate regression analysis revealed that understanding the concept of International Normalized Ratio, knowing the acronym, age, and receiving community counseling after discharge were the strongest predictors of warfarin knowledge. Accessing postdischarge counseling resulted in significantly improved warfarin knowledge scores. Because improved knowledge has been associated with improved compliance and control, our findings support the need to develop a comprehensive postdischarge education program or at least to ensure that patients have access to a community counselor to compliment the in-hospital education program.

The prevalence of thiamin deficiency in hospitalized patients with congestive heart failure.

OBJECTIVES: The purpose of this study was to determine the prevalence of thiamin deficiency (TD) in a cross section of hospitalized congestive heart failure (CHF) patients and to investigate factors that contribute to its development. BACKGROUND: Thiamin deficiency manifests as symptoms of CHF and, therefore, may worsen existing heart failure. Congestive heart failure patients may be at increased risk for TD as a result of diuretic-induced urine thiamin excretion, disease severity, malnutrition, and advanced age. METHODS: Erythrocyte thiamin pyrophosphate concentrations, using high-performance liquid chromatography, were measured in 100 CHF patients and compared to 50 control subjects. Variables including diuretics (type and dose), left ventricle dysfunction, New York Heart Association functional classification, creatinine clearance, thiamin intake (diet and supplements), malnutrition, appetite ratings, and age were related to TD using univariate statistics and multiple logistic regression analysis. RESULTS: Thiamin deficiency was more prevalent in CHF patients (33%) compared to control subjects (12%) (p = 0.007). Thiamin deficiency was related to urine thiamin loss (p = 0.03), non-use of thiamin-containing supplements (p = 0.06), and preserved renal function (p = 0.05). Increased urinary thiamin loss (mug/g creatinine) was found to be the only significant positive predictor of thiamin status on multiple logistic regression analysis (p = 0.03). CONCLUSIONS: One-third of hospitalized CHF patients were TD. In contrast to previous studies, increased urinary losses of thiamin were predictive of improved thiamin status. Thiamin supplementation may be protective against TD in the clinical setting. Future studies are warranted to determine if thiamin supplementation improves thiamin status and disease severity in CHF patients.