Blood Thiamine Concentrations Research Articles

Investigation of Whole Blood Thiamine Concentration in Independently Ambulatory Residents of a Provincial Town in Japan: A Cross-Sectional Study.

Background Thiamine deficiency (TD) is an important public health problem in nutrition, occurring in 2-6% of the population in Europe and the US, whereas thiamine levels are reported to be significantly reduced by 36.6-40% in some populations of East Asia. However, there is little information available at present, regarding factors such as age, despite the continued aging of society. Further, studies such as those mentioned above have not yet been undertaken in Japan, the country in which population aging is most advanced. Objective To investigate TD in the Japanese community-dwelling individuals who are independently ambulatory. Methods We undertook an examination of TD in blood samples obtained from 270 citizens in a provincial town, aged 25-97 years, who were able to walk to the venue and provide informed consent for inclusion in this researchand of whom 8.9% had a history of cancer. We summarized the demographic characteristics of the subjects. The whole-blood thiamine concentrations were measured using the high-performance liquid chromatography method. A value of 21.3 ng/ml or less was taken as low and a borderline value was set as less than 28 ng/ml. Results The mean (±SD) whole blood thiamine concentration was 47.6 ± 8.7 ng/ml. No TD was observed to exist participating in this study, with no subjects even showing show borderline values. Further, there was no significant difference in thiamine level between those aged 65 or older and those aged less than 65. Conclusions No cases of TD were observed among the subjects in this study, nor was the concentration of thiamine found to be related to age. It is possible that the frequency of TD might be very low in citizens who have a certain level of activity. In the future, it is necessary to expand the prevalence of TD to a wider range of subjects.

The prevalence of thiamine deficiency among elderly nursing home residents: A cross-sectional study.

Although thiamine deficiency (TD) can lead to Wernicke encephalopathy, the characteristics associated with TD in the elderly have not yet been clarified. We sought to clarify the frequency of TD among an institutionalized elderly population with a controlled dietary intake and to identify possible factors related to TD. We undertook a cross-sectional study of residents in three nursing homes for the elderly as of June 2020. Blood thiamine concentrations were measured using a high-performance liquid chromatography method, with TD defined as a concentration of <21.3ng/mL. Basic data (age, sex, height, weight, and BMI), dietary intake for the previous 3 weeks, degree of care (DOC), degree of independence in daily life for elderly with dementia (DIDLED), and comorbidities were analyzed using descriptive statistical methods. The mean age (±SD) was 86.9 years (±8.29), with 84 residents (70.0%) being female. The DIDLED varied from total independence to long-term care level 5 (full assistance), with 89.2% suffering dementia. The mean whole blood thiamine value was 36.18 (±17.58) ng/ml, with TD confirmed in 7 (5.8%) of the 120 residents. All TD patients suffered from dementia. No TD was observed in patients with a near-normal food intake, and no related factors were observed among the other items. Reduced food intake may at increase the risk of TD and symptoms of TD may be overlooked in those displaying symptoms of dementia; thus, it is important for clinicians working with the elderly to remain aware of the potential for TD.

Furosemide-related thiamine deficiency in hospitalized hypervolemic patients with renal failure and heart failure

BackgroundWe aimed to describe the thiamine status in hospitalized hypervolemic heart failure (HF) and/or renal failure (RF) patients treated with furosemide and to investigate whether there was a difference in furosemide-related thiamine deficiency between patients with RF and HF. MethodsPatients who were diagnosed as hypervolemia and treated with intravenous furosemide (at least 40mg/day) were included in this prospective observational study. Whole blood thiamine concentrations were measured 3 times during hospital follow-up of patients. ResultsWe evaluated 61 hospitalized hypervolemic patients, of which 22 (36%) were men and 39 (64%) were women, with a mean age of 69.00±10.39 (45–90) years. The baseline and post–hospital admission days 2 and 4 mean thiamine levels were 51.71±20.66ng/ml, 47.64±15.43ng/ml and 43.78±16.20ng/ml, respectively. Thiamine levels of the hypervolemic patients decreased significantly during the hospital stay while furosemide treatment was continuing (p=0.029). There was a significant decrease in thiamine levels in patients who had HF (p=0.026) and also, thiamine was significantly lower in HF patients who had previously used oral furosemide before hospitalization. However, these findings were not present in patients with RF. ConclusionsThiamine substantially decreases in most hypervolemic patients receiving intravenous furosemide treatment during the hospital stay. Thiamine levels were significantly decreased with furosemide treatment in especially HF patients, but the decrease in thiamine levels did not detected at the same rate in RF patients. Diuretic-induced thiamine loss may be less likely in RF patients, probably due to a reduction in excretion.

The effect of cardiopulmonary bypass on blood thiamine concentration and its association with post-operative lactate concentration

ObjectiveCardiothoracic surgery is a large field in Australia, and evidence suggests post-cardiopulmonary bypass (CPB) hyperlactataemia is associated with higher morbidity and mortality. Low thiamine levels are a potentially common yet treatable cause of hyperlactataemia and may occur in the setting of exposure to CPB non-biological material. We hypothesized that cardiopulmonary bypass would result in decreased whole-blood thiamine levels, which may therefore result in increased whole-blood lactate levels in the post-operative period.MethodsAdult patients undergoing non-emergent CPB were recruited in a single centre, prospective, analytic observational study at Townsville University Hospital, Australia. The primary outcome was a comparison of pre- and post-CPB thiamine diphosphate level, secondarily aiming to assess any relationship between lactate and thiamine levels. Prospective pre- and post-CPB blood samples were taken and analysed at a central reference laboratory.ResultsData was available for analysis on 78 patients. There was a statistically significant increase in thiamine diphosphate level from pre-CPB: 1.36 nmol/g Hb, standard deviation (SD) 0.31, 95% confidence intervals (CI) 1.29–1.43, to post-CPB: 1.77 nmol/g Hb, SD 0.53, 95% CI 1.43–1.88, p value < 0.001. There was a non-statistically significant (p > 0.05) trend in rising whole-blood lactate levels with increasing time. Analysis of lactate levels at varying time periods found a significant difference between baseline measurements and increased levels at 13–16 h (p < 0.05). There was no significant relationship observed between whole-blood thiamine levels and post-operative lactate levels.ConclusionWhole-blood thiamine levels were found to increase immediately post-CPB in those undergoing elective cardiac surgery. There was no correlation between whole-blood thiamine levels and post-operative arterial lactate levels.

Evaluation of blood thiamine concentration in hospitalized dogs with and without critical illness.

To evaluate blood thiamine concentration in healthy and critically ill hospitalized dogs over 72hours of hospitalization and to identify any association of thiamine concentration with patient morbidity and mortality. Prospective, observational, clinical study. University veterinary teaching hospital. Thirty-one hospitalized healthy dogs and 37 dogs with critical illness. Dogs with critical illness had nonseptic (n=24) or septic (n=13) etiologies. None. Whole blood EDTA samples were collected within 24hours of admission and 72hours later. Samples were stored at -80°C and batch analyzed. Total thiamine (tB1) and thiamine diphosphate (TDP) concentrations were measured using high-performance liquid chromatography, and free thiamine concentration was determined using liquid chromatography with tandem mass spectrometry. Collected patient data included CBC, biochemistry profile, plasma lactate concentration, shock index, Acute Patient Physiologic and Laboratory Evaluation Score (APPLEfast ) score, comorbid conditions, and patient outcome. Approximately 92% of tB1 present in whole blood is measured as TDP. TDP concentration was strongly correlated with tB1 (R=0.97, P<0.0001). Thiamine concentration, represented by TDP, was not different at admission or at 72hours in all dogs. TDP concentration was lower in septic dogs requiring surgery at admission (P=0.044) and 72hours later (P=0.008), compared to dogs not requiring surgery. TDP concentration was not different between dogs with and without stable chronic diseases at any time point. Older dogs had lower TDP concentration. Positive correlations were seen between TDP and body weight, APPLEfast score, and WBC count. Critically ill dogs with lower admission plasma lactate concentration were more likely to have an increase in thiamine over time (P=0.0142). Differences in thiamine concentration were not identified in hospitalized healthy or critically ill dogs. Further investigation into the clinical relevance of thiamine deficiency is indicated in septic dogs undergoing surgery.

Furosemide-related thiamine deficiency in hospitalized hypervolemic patients with renal failure and heart failure

BackgroundWe aimed to describe the thiamine status in hospitalized hypervolemic heart failure (HF) and/or renal failure (RF) patients treated with furosemide and to investigate whether there was a difference in furosemide-related thiamine deficiency between patients with RF and HF. MethodsPatients who were diagnosed as hypervolemia and treated with intravenous furosemide (at least 40mg/day) were included in this prospective observational study. Whole blood thiamine concentrations were measured 3 times during hospital follow-up of patients. ResultsWe evaluated 61 hospitalized hypervolemic patients, of which 22 (36%) were men and 39 (64%) were women, with a mean age of 69.00±10.39 (45–90) years. The baseline and post–hospital admission days 2 and 4 mean thiamine levels were 51.71±20.66ng/ml, 47.64±15.43ng/ml and 43.78±16.20ng/ml, respectively. Thiamine levels of the hypervolemic patients decreased significantly during the hospital stay while furosemide treatment was continuing (p=0.029). There was a significant decrease in thiamine levels in patients who had HF (p=0.026) and also, thiamine was significantly lower in HF patients who had previously used oral furosemide before hospitalization. However, these findings were not present in patients with RF. ConclusionsThiamine substantially decreases in most hypervolemic patients receiving intravenous furosemide treatment during the hospital stay. Thiamine levels were significantly decreased with furosemide treatment in especially HF patients, but the decrease in thiamine levels did not detected at the same rate in RF patients. Diuretic-induced thiamine loss may be less likely in RF patients, probably due to a reduction in excretion.

Blood thiamine (vitamin B1 ), ascorbic acid (vitamin C), and cortisol concentrations in healthy and ill neonatal foals.

BackgroundSepsis is common in foals and several treatments are used to facilitate recovery. Evidence in people suggests an association between low blood concentrations of thiamine, ascorbic acid, and cortisol and sepsis, with further evidence suggesting that administration of hydrocortisone, thiamine, and ascorbic acid may improve outcome. No information is available with regard to these treatments in foals.Hypothesis/ObjectivesTo compare blood concentrations of thiamine, ascorbic acid, and cortisol in healthy and ill foals.AnimalsFifteen healthy and 27 ill (septic and sick‐nonseptic [SNS]) foals were evaluated at admission. Fewer healthy and ill foals were available for sampling at 72 and 120 hours.MethodsProspective study. Blood was collected from healthy foals at 12 (n = 15), 72 (n = 11), and 120 (n = 9) hours of age and from ill foals <48 hours old at admission (n = 27), 72 (n = 8), and 120 (n = 8) hours after presentation. Thiamine, ascorbic acid, and cortisol concentrations were measured in blood samples and compared between groups of foals.ResultsBlood concentrations of thiamine were significantly lower in septic compared to healthy foals at 72 (median, 1.72 ng/mL; P = .02) and 120 (median, 2.0 ng/mL; P = .04) hours after admission; blood concentrations of ascorbic acid also were significantly lower in septic compared to healthy foals at 72 (median, 4.4 μg/mL; P = .02) and 120 hours (median, 4.8 μg/mL; P = .03). Blood concentrations of ascorbic acid were lower in SNS compared to healthy foals at 72 (median, 6.9 μg/mL; P = .03) and 120 (median, 6.4 μg/mL; P = .04) hours after admission. Serum cortisol concentrations were significantly higher at admission in septic (median, 4.23 μg/dL) compared to SNS (median, 1.8 μg/dL; P = .01) and healthy (median, 2.2 μg/dL; P = .002) foals.Conclusions and Clinical ImportanceA potential association exists between illness in foals and lower blood concentrations of thiamine and ascorbic acid during hospitalization. Additional studies are needed to examine a larger population of foals and determine the clinical impact of low vitamin concentrations, if any, on morbidity and mortality.

The correlation of blood thiamine concentrations with lactate acidosis in peritonitis patients with sepsis

Background: Vitamin B1 (Thiamine) functions as a pyruvate dehydrogenase cofactor to produce acetyl Co-A and activate the Krebs cycle in cellular metabolism. The hypermetabolic state in septic condition requires excess thiamin to keep the Krebs cycle functioning well. The thiamin level in the blood decreases and causes mitochondrial dysfunction and vice versa results in an increase in lactate levels. This study aims to evaluate the correlation of blood thiamine concentrations with lactate acidosis in peritonitis patients with sepsisMethods: Prospective observational study in 65 adult septic patients who came to the hospital with peritonitis and underwent laparotomy. Thiamine concentration was assessed on days 1, 3, and 5 by liquid chromatography-mass spectrometry (LC-MS). The primary outcome was lactate levels. Data was analyzed using SPSS version 23 for Windows.Results: The incidence of thiamine deficiency (TD) was 61.5% of patients. Specifically, 29 cases (44.6%) had absolute thiamine deficiency (TD) on presentation, 4 patients (6.1%) developed it on day 3, and another 7 patients (10.8%) on day 5. Thiamine was negatively correlated with lactate levels (r=-0.600; p=0.020). The relationship appeared after multivariable regression analysis controlling for sex, septic shock, and malnutrition. Overall, for the TD group, there was a significant association with septic shock, malnourishment, and Mortality (p&lt;0.05). Conclusion: Thiamine deficiency had significantly raised lactate levels, which might increase the risk of Mortality.

Oral benfotiamine reverts cognitive deficit and increase thiamine diphosphate levels in the brain of a rat model of neurodegeneration.

It is well known that patients with Alzheimer's disease (AD) have imbalances in blood thiamine concentrations and lower activity of thiamine-dependent enzymes. Benfotiamine, a more bioavailable thiamine analog, has been proposed as an alternative to counteract these changes related to thiamine metabolism. Thus, our study aimed to analyze the effects of benfotiamine supplementation on brain thiamine absorption, as well as on parameters related to neuronal energy metabolism and disease progression in an experimental model of sporadic AD induced by intracerebroventricular injection of streptozotocin (STZ) in rats. The supplementation with 150 mg/kg of benfotiamine for 30 days increased the concentrations of thiamine diphosphate in the hippocampus and entorhinal cortex. This led to an improvement in mitochondria enzymes and insulin signaling pathway, with inactivation of GSK3α/β and ERK1/2, which are two tau-kinases related to the progression of AD, which could decrease tau hyperphosphorylation and apoptosis signaling. Besides, we observed an increased amount of Glun2b subunit of NMDA receptors, decreased inflammation, and improvement of cognitive deficit. Together, these results suggest that benfotiamine could be a potential therapeutic approach in the treatment of sporadic AD.

Thiamin Status in Adults Receiving Chronic Diuretic Therapy Prior to Admission to a Medical Intensive Care Unit: A Pilot Study.

The aim of the study was to determine serum thiamin concentrations in critically ill medical patients who required chronic diuretic drug treatment before admission to a medical intensive care unit (ICU). This prospective study was performed in a medical ICU. Subjects who received diuretic drug therapy for at least 6months prior to ICU admission constituted the diuretic group. The control group was clinically matched adults admitted to the same ICU but without a history of diuretic therapy. A total of 50 subjects were included (25 subjects in each of the diuretic and control groups). In the diuretic group, daily dose of furosemide prior to admission was 40mg/d (range of20-160mg/d). In all subjects, the ICU admission baseline blood thiamin concentrations were 31.2±27.1ng/mL. In the diuretic group, the baseline whole blood thiamin level was significantly lower compared with levels in the control group (15.5±10.7 vs 46.8±29.5ng/mL; P<0.001). On day 2 after entry, thiamin levels remained low (23.2±15.4ng/mL in the diuretic group vs 49±38ng/mL in the control group; P=0.003). Low thiamin levels were found in 96% of patients at baseline and in 72% of patients on the second day in the diuretic group. Adults receiving chronic diuretic therapy and then requiring medical ICU care commonly exhibit thiamin depletion on admission to the ICU and during the initial days of ICU care.

Possible involvement of thiamine insufficiency in heart failure in the institutionalized elderly.

Heart failure is a major manifestation of thiamine deficiency; beriberi. Even thiamine insufficiency, milder than deficiency, may be associated with increased heart failure risk. In this cross-sectional study, the relationship between thiamine insufficiency and heart failure was investigated in the Japanese institutionalized elderly from April to November 2017. Fifty-five subjects in four care facilities were evaluated for their whole blood thiamine and plasma brain natriuretic peptide concentrations. Mean whole blood thiamine concentration was 88.7 ± 22.3 nmol/L in men and 92.0 ± 16.5 nmol/L in women, and significantly and negatively correlated with plasma brain natriuretic peptide concentrations (r = −0.378, p = 0.007). In the multiple regression analysis adjusted by age, sex, body mass index, and eGFR, whole blood thiamine concentration was a significant negative contributor (standardized coefficient β = −0.488, p = 0.001) to plasma brain natriuretic peptide. In the logistic regression analysis adjusted by the same variables, whole blood thiamine concentration significantly contributed to plasma brain natriuretic peptide concentration higher than over 40 pg/ml (OR: 0.898, 95%CI: 0.838–0.962). Whole blood thiamine concentration in subjects with diuretics was significantly lower than those without it (p = 0.023). Thiamine insufficiency was related to increased plasma brain natriuretic peptide concentration and may increase the risk of heart failure.

Thiamine status in end-stage chronic kidney disease patients: a single-center study.

Reportedly, thiamine deficiency, resulting from malnutrition and long-term diuretic therapy, is observed in patients with chronic kidney disease (CKD). The risk of thiamine deficiency might be enhanced, especially in end-stage CKD patients. Here, we assessed thiamine status in incident dialysis patients. This study was a single-center cross-sectional study which included 288 consecutive patients initiated into dialysis between April 2013 and March 2017 at our hospital. Thiamine status was evaluated by high-performance liquid chromatography of whole blood samples. We evaluated the association between blood thiamine concentration and other clinical parameters. Of the 288 patients, 21 patients receiving thiamine supplementation at the time of dialysis initiation and 26 patients without blood thiamine measurements were excluded. In 30 patients (12.4%), blood thiamine concentration was lower than the lower limit of normal (21.3ng/mL; dotted line). Blood thiamine concentration correlated with age, body mass index, and Barthel index (BI) score (p = 0.008, 0.012 and 0.009, respectively). Stepwise multivariate regression analysis indicated that BI scores were independent risk factors for thiamine deficiency (β coefficients = 0.169, p = 0.013). The proportion of end-stage CKD patients with low blood thiamine concentration is high. Low physical function (low BI score) is an independent risk factor of thiamine deficiency. Clinicians should be aware of thiamine deficiency in end-stage CKD patients, especially those with low physical function.

Thiamine status, metabolism and application in dairy cows: a review.

As the co-enzyme of pyruvate dehydrogenase and α-ketoglutarate dehydrogenase, thiamine plays a critical role in carbohydrate metabolism in dairy cows. Apart from feedstuff, microbial thiamine synthesis in the rumen is the main source for dairy cows. However, the amount of ruminal thiamine synthesis, which is influenced by dietary N levels and forage to concentrate ratio, varies greatly. Notably, when dairy cows are overfed high-grain diets, subacute ruminal acidosis (SARA) occurs and results in thiamine deficiency. Thiamine deficiency is characterised by decreased ruminal and blood thiamine concentrations and an increased blood thiamine pyrophosphate effect to >45 %. Thiamine deficiency caused by SARA is mainly related to the increased thiamine requirement during high grain feeding, decreased bacterial thiamine synthesis in the rumen, increased thiamine degradation by thiaminase, and decreased thiamine absorption by transporters. Interestingly, thiamine deficiency can be reversed by exogenous thiamine supplementation in the diet. Besides, thiamine supplementation has beneficial effects in dairy cows, such as increased milk and component production and attenuated SARA by improving rumen fermentation, balancing bacterial community and alleviating inflammatory response in the ruminal epithelium. However, there is no conclusive dietary thiamine recommendation for dairy cows, and the impacts of thiamine supplementation on protozoa, solid-attached bacteria, rumen wall-adherent bacteria and nutrient metabolism in dairy cows are still unclear. This knowledge is critical to understand thiamine status and function in dairy cows. Overall, the present review described the current state of knowledge on thiamine nutrition in dairy cows and the major problems that must be addressed in future research.

Micronutrient Alterations During Continuous Renal Replacement Therapy in Critically Ill Adults: A Retrospective Study.

Continuous renal replacement therapy (CRRT) is commonly used to provide renal replacement therapy in the intensive care unit. Limited published data suggest that CRRT may lead to depletion of water-soluble vitamins and trace elements. The goal of this study was to identify the incidence of trace element and vitamin deficiencies in critically ill patients during CRRT. This study is based on a retrospective chart review of patients who were referred to Emory University Hospital's nutrition support services and had at least 1 serum micronutrient level measured during CRRT (thiamin, pyridoxine, ascorbic acid, folate, zinc, and copper) between April 1, 2009, and June 1, 2012. Seventy-five patients were included in the study. Nine of 56 patients (16%) had below-normal whole blood thiamin concentrations, and 38 of 57 patients (67%) had below-normal serum pyridoxine levels. Serum ascorbic acid and folate deficiencies were identified among 87% (13 of 15) and 33% (3 of 9) of the study patients, respectively. Nine of 24 patients had zinc deficiency (38%), and 41 of 68 patients had copper deficiency (60%). Of the 75 total subjects, 60 patients (80%) had below-normal levels of at least 1 of the micronutrients measured. The incidence of various micronutrient deficiencies in critically ill patients who required CRRT was higher than previously reported. Prospective studies are needed to determine the impact of CRRT on micronutrient status and the potential clinical and metabolic efficacy of supplementation in the intensive care unit setting.

Effect of blood thiamine concentrations on mortality: Influence of nutritional status.

To test the hypothesis that low blood thiamine concentrations in malnourished critically ill children are associated with higher risk of 30-d mortality. Prospective cohort study in 202 consecutively admitted children who had whole blood thiamine concentrations assessed on admission and on days 5 and 10 of intensive care unit (ICU) stay. The primary outcome variable was 30-d mortality. Mean blood thiamine concentrations within the first 10 d of ICU stay, age, sex, malnutrition, C-reactive protein concentration, Pediatric Index of Mortality 2 score, and severe sepsis/septic shock were the main potential exposure variables for outcome. Thiamine deficiency was detected in 61 patients within the first 10 d of ICU stay, 57 cases being diagnosed on admission and 4 new cases on the 5th d. C-reactive protein concentration during ICU stay was independently associated with decreased blood thiamine concentrations (P = 0.003). There was a significant statistical interaction between mean blood thiamine concentrations and malnutrition on the risk of 30-d mortality (P = 0.002). In an adjusted analysis, mean blood thiamine concentrations were associated with a decrease in the mortality risk in malnourished patients (odds ratio = 0.85; 95% confidence interval [CI]: 0.73-0.98; P = 0.029), whereas no effect was noted for well-nourished patients (odds ratio: 1.03; 95% CI: 0.94-1.13; P = 0.46). Blood thiamine concentration probably has a protective effect on the risk of 30-d mortality in malnourished patients but not in those who were well nourished.

Thiamine deficiency in tachypnoeic Cambodian infants

Background:Beriberi is endemic in South-east Asia. Diagnosis is based on clinical findings, but correlation of clinical features with blood thiamine concentrations is uncertain.Objectives:To investigate in tachypnoeic Cambodian infants the correlation between whole blood thiamine diphosphate (TDP) concentrations, clinical findings and blood TDP levels after therapy.Methods:Infants hospitalised with tachypnoea were enrolled from October 2011 to January 2012. Initial clinical features, diagnostic test results and final diagnoses were recorded. Blood for TDP determination was collected prior to treatment and at discharge. Matched infants from the general outpatient clinic with minor complaints were enrolled as controls. Thiamine was administered at the discretion of the treating paediatrician.Results:Of the 47 tachypnoeic and 47 control infants, median initial blood TDP concentrations were 83 and 93 nmol/L, respectively (P = 0·69), and were below the estimated limit of normal (<70 nmol/L) in 43% vs 34% (P = 0·40). Median initial TDP levels were 72 and 91 nmol/L in tachypnoeic infants who did or did not receive thiamine, respectively (P = 0·56); at hospital discharge, median TDP concentration had increased by 107 and 3·5 nmol/L in these two subgroups (P<0·001). Classical findings of beriberi such as dysphonia, tachycardia and hepatomegaly did not correlate with low initial TDP concentrations, but infant age, Tiger Balm use, absence of wheezing and low blood CRP levels were associated with low initial TDP levels. Use of infant formula was associated with higher initial TDP levels.Conclusions:Thiamine deficiency is common in tachypnoeic Cambodian infants, but routine clinical assessments do not accurately identify those with low blood TDP concentrations. Parenteral thiamine administration markedly increases TDP levels. Empirical thiamine treatment should be considered for tachypnoeic infants in regions with endemic thiamine deficiency.

Influence of intravenous thiamine supplementation on blood lactate concentration prior to cardiac surgery: A double-blinded, randomised controlled pilot study.

Stress related to surgery and critical illness depletes thiamine, essential in energy metabolism, and might result in high blood lactate concentrations and higher mortality. We hypothesised that thiamine supplementation would increase blood concentration of thiamine and reduce blood lactate concentration postoperatively. Moreover, we aimed to identify the prevalence of, and risk factors for, high blood lactate concentrations. This was a double-blind, randomised controlled pilot study from February to July 2012 including 30 patients scheduled for cardiac surgery with cardiopulmonary bypass. Patients were assigned randomly to receive thiamine (300 mg in 0.9% Normal saline solution) or placebo (0.9% Normal saline) preoperatively. One arterial blood sample was taken preoperatively and another postoperatively to measure thiamine concentration, and multiple samples were taken during surgery and ICU stay to determine lactate concentrations. Twenty-four hour urine samples were collected to measure urinary thiamine concentration. Preoperatively, we assessed extracellular mass to body cell mass ratio (ECM/BCM). The mean (SD) age of the patients was 58 (12) years, 73% were overweight, 10% were malnourished and the prevalence of thiamine deficiency was 10%. Patients in the thiamine group had significantly higher blood thiamine concentrations 2 days postoperatively [805.2 ± 289.8 ng g(-1) haemoglobin (Hb)] than those in the placebo group (591.2 ± 100.7 ng g(-1) Hb, P < 0.01). The mean blood lactate concentration changed significantly over time, but did not differ significantly between the groups. Patients with ECM/BCM more than 1 had higher lactate concentrations on admission to ICU than those with ECM/BCM less than 1 (2.1 ± 0.7 vs. 1.7 ± 0.6, P = 0.09) and were at a significantly greater risk of having a higher lactate concentration on ICU admission [odds ratio (OR) 13.5, 95% confidence interval (95% CI) 1.0 to 179.4, P < 0.05]. On the basis of these results, a sample size calculation for a larger study has been facilitated. Thiamine supplementation caused normalisation of blood and urine concentrations postoperatively but without a significant reduction in lactate concentration or clinical outcome. Body composition played an important role in lactate formation. Further research focusing on preoperative screening and optimal treatment of high lactate concentrations in this specific population is warranted. Clinicaltrials.gov identifier: NCT01524315.

Thiamine deficiency in tachypnoeic Cambodian infants.

Background: Beriberi is endemic in South-east Asia. Diagnosis is based on clinical findings, but correlation of clinical features with blood thiamine concentrations is uncertain. Objectives: To investigate in tachypnoeic Cambodian infants the correlation between whole blood thiamine diphosphate (TDP) concentrations, clinical findings and blood TDP levels after therapy. Methods: Infants hospitalised with tachypnoea were enrolled from October 2011 to January 2012. Initial clinical features, diagnostic test results and final diagnoses were recorded. Blood for TDP determination was collected prior to treatment and at discharge. Matched infants from the general outpatient clinic with minor complaints were enrolled as controls. Thiamine was administered at the discretion of the treating paediatrician. Results: Of the 47 tachypnoeic and 47 control infants, median initial blood TDP concentrations were 83 and 93 nmol/L, respectively (P = 0·69), and were below the estimated limit of normal (<70 nmol/L) in 43% vs 34% (P = 0·40). Median initial TDP levels were 72 and 91 nmol/L in tachypnoeic infants who did or did not receive thiamine, respectively (P = 0·56); at hospital discharge, median TDP concentration had increased by 107 and 3·5 nmol/L in these two subgroups (P<0·001). Classical findings of beriberi such as dysphonia, tachycardia and hepatomegaly did not correlate with low initial TDP concentrations, but infant age, Tiger Balm use, absence of wheezing and low blood CRP levels were associated with low initial TDP levels. Use of infant formula was associated with higher initial TDP levels. Conclusions: Thiamine deficiency is common in tachypnoeic Cambodian infants, but routine clinical assessments do not accurately identify those with low blood TDP concentrations. Parenteral thiamine administration markedly increases TDP levels. Empirical thiamine treatment should be considered for tachypnoeic infants in regions with endemic thiamine deficiency.

Effectiveness of B vitamin supplementation following bariatric surgery: rapid increases of serum vitamin B12.

Few prospective studies have compared changes of nutrient intake while assessing effectiveness of thiamin, vitamin B12, and folate supplementation to prevent B vitamin deficiencies immediately following Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). Therefore, we determined the response to 3 months supplementation on maintaining blood B vitamin concentrations. Women undergoing RYGB (n = 11) and SG (n = 11) consumed bariatric vitamin supplements (12 mg thiamin, 350 μg vitamin B12, 800 μg folic acid) daily for 3 months. Height, weight, body mass index, and blood vitamin concentrations were measured preoperatively and at 3 months. Wilcoxon signed-rank analyses compared body weight parameters, laboratory indices, and nutrient intake at baseline and 3 months. Supplementation for 3 months maintained blood thiamin, increased serum folate from 13.1 ± 5.4 to 16.3 ± 6.0 nmol/L (P = 0.049), and increased serum vitamin B12 concentrations from 498 ± 150 to 736 ± 340 pg/mL (P = 0.005). Dietary intake of thiamin and folate decreased in the combined surgical groups, while dietary intake of B12 was maintained. Bariatric B vitamin supplements provided multiple intakes of the Recommended Dietary Allowances (1090% thiamin, 14,583% vitamin B12, 200% folate). Although energy intake decreased 64%, B vitamin supplementation for 3 months resulted in a 48% increase of serum vitamin B12, a modest increase of serum folate, and no reduction of blood thiamin concentrations. Long-term effects of the rapid rise of serum B12 levels attributed to the high content of supplements warrant further investigation.

Thiamine Deficiency and Cardiac Dysfunction in Cambodian Infants

To compare blood thiamine concentrations, echocardiography findings, and plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels in infants with clinically diagnosed beriberi and healthy matched controls, and to evaluate changes after thiamine treatment. Sixty-two Cambodian infants (20 cases and 42 controls), aged 2-47 weeks, were enrolled in this prospective study. Echocardiography and phlebotomy were performed at baseline and after thiamine treatment. Both cases and controls were thiamine-deficient, with median blood thiamine diphosphate (TDP) concentrations of 47.6 and 55.1 nmol/L, respectively (P = .23). All subjects had normal left ventricular ejection fraction. The median NT-proBNP concentration in cases (340 pg/mL [40.1 pmol/L]) was higher than previously reported normal ranges, but not statistically significantly different from that in controls (175 pg/mL [20.7 pmol/L]) (P = .10), and was not correlated with TDP concentration (P = .13). Two cases with the lowest baseline TDP concentrations (24 and 21nmol/L) had right ventricular enlargement and elevated NT-proBNP levels that improved dramatically by 48hours after thiamine administration. Only a minority of thiamine-deficient Cambodian infants demonstrate abnormal echocardiography findings. Thiamine deficiency produces echocardiographic evidence of right ventricular dysfunction, but this evidence is not apparent until deficiency is severe. NT-proBNP concentrations are mildly elevated in sick infants with normal echocardiography findings, indicating possible physiological changes not yet associated with echocardiographic abnormalities.