Thiamine utilization and the lack of prescribing standardization: A critical examination

OBJECTIVES

Thiamine is often prescribed for thiamine deficiency during hospitalization despite the lack of US-based clinical guidelines. This study aims to evaluate thiamine prescribing patterns and key characteristics associated with the deficiency to address gaps in care.

METHODS

Data were obtained from electronic health records of hospitalized patients between September 1, 2021, and March 30, 2022. Alcohol use disorder (AUD) was defined by a positive Clinical Institute Withdrawal Assessment score or a positive serum alcohol level upon admission. Geriatric patients were defined as age ≥65. Cohort 1 was defined as: AUD, albumin <4 g/L, INR >1.5, and total bilirubin >3 mg/dL. Cohort 2 was defined as: age >65, albumin <4 g/L, hemoglobin <15 g/dL, and folate <4 ng/mL. A multivariable LASSO regression model was used to identify characteristics associated with higher thiamine dosing (>100 mg/day).

RESULTS

Among 780 patients, 520 (66.7%) were identified as AUD, of which 265 (50.1%) were between the ages of 45-64 years. The AUD cohort was significantly different (p < 0.05) in the mean serum albumin 4.16 g/L (IQR: 3.8-4.5), AST 73.55 U/L (23.75-82.00), ALT 52.57 U/L (17.00-57.00), total bilirubin 0.98 (0.3-1.0), and INR 1.1 (0.99-1.12), compared to non-AUD patients with a mean serum albumin 3.75 g/L (3.3-4.2), AST 35.07 U/L (11.00-42.00), ALT 32.77 U/L (5.00-34.00), total bilirubin 0.89 (0.2-0.9), and INR 1.21 (1.0-1.22). In the geriatric cohort, 136 patients (17%) had a mean serum albumin 3.77 g/L (3.4-4.2), AST 38.66 U/L (14.0-41.0), ALT 29.36 U/L (9.0-37.0), total bilirubin 0.62 mg/dL (0.30-0.90), and direct bilirubin 0.12 mg/dL (0.00-0.20), compared to the non-geriatric cohort with a mean serum albumin 4.10 g/L (3.8-4.40), AST 66.44 U/L (21.0-75.0), ALT 50.03 U/L (16.00-53.75), total bilirubin 1.02 mg/dL (0.30-1.00), and direct bilirubin 0.31 mg/dL (0.00-0.20). In cohort 1, 40.6% patients were between 51 and 64 years old, (66.5%) male, and had a BMI <25 (36.4%). In cohort 2, 52.6% were between 65 and 70 years old, (57.9%) male, and had a BMI <25 (57.9%). Cohort 1 were prescribed a dose of 100 mg (47.7 %), oral (63.5%), intramuscular (18.2%), daily (58.9%), one-day duration (49.4%) most frequently. Cohort 2 were prescribed a dose of 100 mg (56.0%), oral (77.2%), daily (77.2%), one-day duration (29.8%) most frequently. The AUD was significantly associated with having a higher dosage (e.g., >100 mg) of thiamine prescribed per day OR 1.62 (1.11-2.37) (p < 0.01).

CONCLUSIONS

This study confirms that thiamine prescribing patterns vary during hospitalization and suggest specific laboratory findings may aid in identifying cohorts associated with the deficiency.

Thiamine deficiency in Gambian women of reproductive age

Thiamine deficiency disorders are associated with a variety of clinical symptoms affecting the nervous and cardiovascular systems. There is growing recognition that thiamine deficiency can occur in populations well beyond the classical region of South Asia, and at-risk populations include those who receive a large proportion of their energy from polished white rice (or other low-thiamine staple foods) and with low dietary diversity. Reports of thiamine deficiency in West Africa over the last century have suggested that this has historically been an issue in this population, but in more recent decades, these reports have been limited to prison populations. To understand if thiamine deficiency might be an unrecognized problem in the communities of this region, erythrocyte samples collected during the wet and dry seasons from 226 women of reproductive age (mean age = 28 years old) were assessed for thiamine status by measuring the erythrocyte transketolase activity coefficient (ETKac). Overall, 35.8% of the sample was at high risk of thiamine deficiency (ETKac ≥ 1.25). Risk of thiamine deficiency was significantly higher in the wet (47.9%) compared with the dry season (22.9%) (P < 0.001). To our knowledge, this is the first report of biochemical thiamine deficiency in a free-living population in West Africa in the 21st century and suggests that further investigation is warranted.

The Relevance of Thiamine Evaluation in a Practical Setting

Thiamine is a crucial cofactor involved in the maintenance of carbohydrate metabolism and participates in multiple cellular metabolic processes. Although thiamine can be obtained from various food sources, some common food groups are deficient in thiamine, and it can be denatured by high temperature and pH. Additionally, different drugs can alter thiamine metabolism. In addition, the half-life of thiamine in the body is between 1 and 3 weeks. All these factors could provide an explanation for the relatively short period needed to develop thiamine deficiency and observe the consequent clinical symptoms. Thiamine deficiency could lead to neurological and cardiological problems. These clinical conditions could be severe or even fatal. Marginal deficiency too may promote weaker symptoms that might be overlooked. Patients undergoing upper gastrointestinal or pancreatic surgery could have or develop thiamine deficiency for many different reasons. To achieve the best outcome for these patients, we strongly recommend the execution of both an adequate preoperative nutritional assessment, which includes thiamine evaluation, and a close nutritional follow up to avoid a nutrient deficit in the postoperative period.

Wernicke encephalopathy in a patient after liver transplantation: A case report

Wernicke encephalopathy (WE) is an acute neurological disorder resulting from vitamin B1 deficiency, which is common in chronic alcoholism and is rare in acute liver failure. So far, there are 2 cases of WE reported after liver transplantation. Here, we report a case of a 45-year-old nonalcoholic male patient who developed psychiatric and neurological disturbance 15 d after receiving orthotopic liver transplantation because of hepatitis B-related cirrhosis and portal hypertension. Brain magnetic resonance imaging (MRI) showed symmetric high-signal intensities in the periaqueductal area. The patient was diagnosed with WE and given intravenous high-dose vitamin B1 immediately. His neurological disturbance resolved in 7 d after receiving the vitamin B1. Brain MRI after 5 mo showed nearly complete recovery. Most WE cases may be misdiagnosed in patients after liver transplantation, and we should pay more attention to its onset.

The effect of subclinical infantile thiamine deficiency on motor function in preschool children

We investigated the long-term implications of infantile thiamine (vitamin B1) deficiency on motor function in preschoolers who had been fed during the first 2 years of life with a faulty milk substitute. In this retrospective cohort study, 39 children aged 5-6 years who had been exposed to a thiamine-deficient formula during infancy were compared with 30 age-matched healthy children with unremarkable infant nutritional history. The motor function of the participants was evaluated with The Movement Assessment Battery for Children (M-ABC) and the Zuk Assessment. Both evaluation tools revealed statistically significant differences between the exposed and unexposed groups for gross and fine motor development (p < .001, ball skills p = .01) and grapho-motor development (p = .004). The differences were especially noteworthy on M-ABC testing for balance control functioning (p < .001, OR 5.4; 95% CI 3.4-7.4) and fine motor skills (p < .001, OR 3.2; 95% CI 1.8-4.6). In the exposed group, both assessments concurred on the high rate of children exhibiting motor function difficulties in comparison to unexposed group (M-ABC: 56% vs. 10%, Zuk Assessment: 59% vs. 3%, p < .001). Thiamine deficiency in infancy has long-term implications on gross and fine motor function and balance skills in childhood, thiamine having a crucial role in normal motor development. The study emphasizes the importance of proper infant feeding and regulatory control of breast milk substitutes.

[Thiamine in patients with alcohol use disorder and Wernicke's encephalopathy]

- Patients with alcohol use disorder frequently have a thiamine deficiency.- A potential life-threatening complication of thiamine deficiency is Wernicke's encephalopathy.- Since it is clinically difficult to recognize Wernicke's encephalopathy, this condition is often treated inadequately. - Early supplementation of thiamine is important to avoid irreversible neurological damage. - There are differences between the Dutch guidelines regarding the supplementation of thiamine for the treatment of alcoholic use disorder, and those for Wernicke's encephalopathy. - There are no solid evidence-based recommendations about the best dosage, route of administration and duration of thiamine supplementation for the treatment of alcohol use disorder and Wernicke's encephalopathy. - Based on the pharmacokinetic properties of thiamine, it is more appropriate to give patients with alcohol use disorder 25 mg four times a day rather than 50 mg twice a day. - Patients at high risk of Wernicke's encephalopathy should immediately receive an intravenous or intramuscular dose of thiamine; patients with suspected Wernicke's encephalopathy should preferably receive an intravenous dose.- Reports of anaphylactic reaction to parenteral administration of thiamine are rare and are not a reason to refrain from parenteral treatment.

Interactions between chronic ethanol consumption and thiamine deficiency on neural plasticity, spatial memory, and cognitive flexibility

BACKGROUND

Many alcoholics display moderate to severe cognitive dysfunction accompanied by brain pathology. A factor confounded with prolonged heavy alcohol consumption is poor nutrition, and many alcoholics are thiamine deficient. Thus, thiamine deficiency (TD) has emerged as a key factor underlying alcohol-related brain damage (ARBD). TD in humans can lead to Wernicke Encephalitis that can progress into Wernicke-Korsakoff syndrome and these disorders have a high prevalence among alcoholics. Animal models are critical for determining the exact contributions of ethanol (EtOH)- and TD-induced neurotoxicity, as well as the interactions of those factors to brain and cognitive dysfunction.

METHODS

Adult rats were randomly assigned to 1 of 6 treatment conditions: chronic EtOH treatment (CET) where rats consumed a 20% v/v solution of EtOH over 6 months; severe pyrithiamine-induced TD (PTD-moderate acute stage); moderate PTD (PTD-early acute stage); moderate PTD followed by CET (PTD-CET); moderate PTD during CET (CET-PTD); and pair-fed (PF) control. After recovery from treatment, all rats were tested on spontaneous alternation and attentional set-shifting. After behavioral testing, brains were harvested for determination of mature brain-derived neurotrophic factor (BDNF) and thalamic pathology.

RESULTS

Moderate TD combined with CET, regardless of treatment order, produced significant impairments in spatial memory, cognitive flexibility, and reductions in brain plasticity as measured by BDNF levels in the frontal cortex and hippocampus. These alterations are greater than those seen in moderate TD alone, and the synergistic effects of moderate TD with CET lead to a unique cognitive profile. However, CET did not exacerbate thalamic pathology seen after moderate TD.

CONCLUSIONS

These data support the emerging theory that subclinical TD during chronic heavy alcohol consumption is critical for the development of significant cognitive impairment associated with ARBD.

Biochemical changes correlated with blood thiamine and its phosphate esters levels in patients with diabetes type 1 (DMT1)

Thiamine (vitamin B1) is an essential enzyme cofactor in most organisms required at several stages of anabolic and catabolic intermediary metabolism. However, little is known on the positive effects of thiamine in diabetic type 1 (DMT1) patients. The objectives of this study were to evaluate the biochemical changes related to thiamine deficiency in patients with DMT1 outcomes among Saudi adults. We hypothesized that blood thiamine deficiency in patients with DMT1 manifestations might lead to an increase in metabolic syndrome. A total of 77 patients with DMT1 (age 35.8 ± 5.5) and 81 controls (age 45.0 ± 18.1) (total N = 158) were randomly selected from the Riyadh Cohort Study for inclusion. Saudi adults with diabetes type 1, a significant decrease in systolic (P < 0.001), and diastolic blood pressure (P = 0.008) and microalbuminuria (P = 0.02). Moreover, cholesterol, glucose and triglycerides were significantly increased (P 0.001, 0.001 and 0.008, respectively) in patients with diabetes type 1 compared to controls. On the other hand, HDL, TMP, TDP and thiamine, were significantly decreased in patients with diabetes type 1 (P 0.005, 0.002, 0.005, and 0.002), respectively. A strong association between blood thiamine level and diabetes type 1 was detected in our study population. The results confirmed the role of thiamine and thiamine phosphate esters, in preventing metabolic changes and complications of diabetes type 1. The levels of these thiamine and thiamine phosphate esters were correlated with diabetes related biomarkers including HDL, glucose, triglycerides and cholesterol, as well as microalbuminuria, LDL and urine thiamine. The results support a pivotal role of blood thiamine and its phosphate esters in preventing the biochemical changes and complications in patients with DMT1.

Thiamin concentration in geriatric hospitalized patients using frusemide

AIM

To assess the association between thiamin concentration, frusemide use, and renal function in older adults.

METHOD

Thiamin concentration was measured in 73 consecutive admissions of patients aged over 65 years in a secondary care hospital. The patients were assigned to the study or control group based on frusemide use. A two-sample t test estimated the association between frusemide use and thiamin concentration and regression between thiamin concentration and EGFR.

RESULTS

The mean (SD) thiamin concentration was 181.7 (64.6) nmol/L in those using frusemide and 169.3 (46.8) in non-users, P =0.35. There was a weak linear relationship between thiamin concentration and EGFR, with thiamin concentration being 17.0 nmol/L lower per 30 ml/min greater EGFR, P=0.076. Thiamin concentration was below the reference range in 20/73 (27.4%) of the participants.

CONCLUSION

We found no association between frusemide use and thiamin concentration, but showed a significant prevalence of lower thiamin concentration in the study population of older adults.

Thiamine deficiency and its correlation with dyslipidaemia in diabetics with microalbuminuria

OBJECTIVE

To measure and correlate the levels of thiamine and dyslipidaemia in microalbuminuric diabetics.

METHODS

Cross-sectional comparative study was conducted at the Department of Biochemistry and Molecular Biology, Army Medical College, Rawalpindi, from January 2009 to December 2010, and comprised 60 known diabetic patients, who were inducted from diabetic clinics of Rawalpindi. These patients were divided into three equal groups, with group I (n=20) being normal healthhy individuals, group II comprised of microalbuminurics type 2 diabetics (n=20) and group III (n=20) were macroalbuminuric type 2 diabetics, based on their albumin excretion rate. The healthy volunteers (n=20) had blood glucose less than 6 mmol/L and were inducted as the comparison group. Fasting blood samples of diabetic and control groups were analysed for glucose, glycosylated haemoglobin, lipid profile, thiamine chloride and thiamine monophosphate. Besides, 24-hour urine samples were analysed for microalbuminuria, thiamine chloride and thiamine monophosphate.

RESULTS

Plasma thiamine chloride and thiamine monophosphate levels were found to be significantly (p<0.001) reduced in the diabetics (n=60) compared to the controls (n=20). Furthermore, there was a progressive decline in these levels with increasing albuminuria; the lowest being in the macroalbuminuric group (group IV). Urinary thiamine levels were significantly (p<0.001) higher in the diabetics compared to the controls. These changes were more pronounced as albuminuria level increased; the highest being in group IV. The parameters of lipid profile, including triglycerides, total cholesterol and low-density lipoprotein cholesterol, were significantly (p<0.001) higher in diabetics and showed progressive increase with worsening albuminuria. Whereas, the high-density lipoprotein cholesterol levels were significantly (p<0.001) reduced in diabetics and showed progressive decline as the microalbuminuria status worsened. Furthermore, a significant negative correlation was found between plasma thiamine and all the parameters of lipid profile except high-density lipoprotein cholesterol which had a significant positive correlation. A significant linear regression of microalbuminuria on plasma thiamine was also found.

CONCLUSION

Thiamine levels were reduced in the diabetic population and this reduction in thiamine level was negatively correlated with lipid profile in microalbuminuric diabetics.

[Vitamin and mineral status of oarsmen during the training-competition cycles]

Vitamin and minerals status of 30 sportsmen aged 16.8 +/- 0.2 years (trained in boat racing 5.0 +/- 0.3 years) during the training--competition cycles in autumn and winter has been studied. A significant decrease of vitamin A level in the range of reference limits was found in 30.8% of sportsmen during autumn season, but such decrease was revealed in 100% of examined sportsmen during winter Vitamin B1 and B2 deficiency has been detected in both seasons. The portion of persons with vitamin B2 deficiency increased during training cycles. A significant decrease of magnesium (in 56.3% of sportsmen) and sodium level (in 33.3% of sportsmen) was detected during autumn season. Irrespective of the season a significant decrease of blood serum of calcium (in 40.0-66.7% of sportsmen); potassium (in 53.3-66.7% of sportsmen according to both absolute and individual data); chlorides (in 50.0-90.0% of sportsmen), and iron (in 53.3-60.0% of sportsmen) has been revealed. The data obtained indicate the need for diagnostics and correction of vitamin and minerals status in sportsmen.

Thiamine diphosphate in whole blood, thiamine and thiamine monophosphate in breast-milk in a refugee population

BACKGROUND

The provision of high doses of thiamine may prevent thiamine deficiency in the post-partum period of displaced persons.

METHODOLOGY/PRINCIPAL FINDINGS

The study aimed to evaluate a supplementation regimen of thiamine mononitrate (100 mg daily) at the antenatal clinics in Maela refugee camp. Women were enrolled during antenatal care and followed after delivery. Samples were collected at 12 weeks post partum. Thiamine diphosphate (TDP) in whole blood and thiamine in breast-milk of 636 lactating women were measured. Thiamine in breast-milk consisted of thiamine monophosphate (TMP) in addition to thiamine, with a mean TMP to total thiamine ratio of 63%. Mean whole blood TDP (130 nmol/L) and total thiamine in breast-milk (755 nmol/L) were within the upper range reported for well-nourished women. The prevalence of women with low whole blood TDP (<65 nmol/L) was 5% and with deficient breast-milk total thiamine (<300 nmol/L) was 4%. Whole blood TDP predicted both breast-milk thiamine and TMP (R(2) = 0.36 and 0.10, p<0.001). A ratio of TMP to total thiamine ≥63% was associated with a 7.5 and 4-fold higher risk of low whole blood TDP and deficient total breast-milk thiamine, respectively. Routine provision of daily 100 mg of thiamine mononitrate post-partum compared to the previous weekly 10 mg of thiamine hydrochloride resulted in significantly higher total thiamine in breast-milk.

CONCLUSIONS/SIGNIFICANCE

Thiamine supplementation for lactating women in Maela refugee camp is effective and should be continued. TMP and its ratio to total thiamine in breast-milk, reported for the first time in this study, provided useful information on thiamine status and should be included in future studies of breast-milk thiamine.

Thiamine deficiency in diabetes mellitus and the impact of thiamine replacement on glucose metabolism and vascular disease

Despite the targeting of traditional risk factors for cardiovascular disease, disease burden has not been completely eliminated. Thiamine is an essential cofactor in carbohydrate metabolism and individuals with diabetes are thiamine deficient. The pathophysiology of recognised complications of thiamine deficiency is similar to that underlying atherosclerosis and the metabolic syndrome, namely oxidative stress, inflammation and endothelial dysfunction. This review examines the mechanisms by which thiamine deficiency occurs in individuals with diabetes, how this deficiency leads to hyperglycaemic-induced damage, and the effect of thiamine replacement on vascular disease, endothelial function and oxidative stress. Thiamine administration can prevent the formation of harmful by-products of glucose metabolism, reduce oxidative stress and improve endothelial function. The potential benefit of long-term replacement in those with diabetes is not yet known but may reduce cardiovascular risk and angiopathic complications.

[Measurement of thiamine concentration in the cat using high pressure liquid chromatography]

OBJECTIVE

Thiamine deficiency in cats frequently leads to a dysfunction of the central nervous system including vestibular signs with fatal outcome in untreated cases. The aim of the present study was to directly measure thiamine concentrations using high pressure liquid chromatography (HPLC) in feline blood samples and to evaluate values in healthy and diseased cats.

MATERIAL AND METHODS

Blood samples (1 ml EDTA-whole blood) from 193 cats were analysed for total thiamine and thiamine diphosphate using HPLC. For the interpretation of the results cats were retrospectively assigned to six groups: A) healthy cats, B) cats with diseases of the gastrointestinal tract, C) cats with different traumas not affecting the gastrointestinal tract, D) cats with inappetence, cats with central vestibular signs and normal (E) or low values of thiamine (F), respectively.

RESULTS

In animals of group F no obvious cause for the vestibular signs was found and spontaneous recovery after thiamine application occurred in three cats. Therefore thiamine deficiency was a highly likely clinical diagnosis. Total thiamine concentration (mean 48.2 µg/l, standard deviation ± 22.6) of group F significantly differered from the other groups (group A-D: p<0.01, group E: p<0.001). Comparable results were obtained for thiamine diphosphate. However, low total thiamine values were also found in cats with inappetence without any neurological signs.

CONCLUSION AND CLINICAL RELEVANCE

In the present study a method for direct measurement of thiamine formerly established for ruminants was evaluated for cats. A more accurate and objective clinical diagnosis of thiamine deficiency is feasible in cats with values less than 50 µg/l and typical clinical signs. In animals with values of total thiamine levels between 50-70 µg/l a prophylactic substitution of thiamine can be discussed.

Thiamine status of feedlot cattle fed a high-concentrate diet

As thiamine status of ruminants is adversely affected by rumen acidity, this study investigated whether or not thiamine deficiency occurs in feedlot cattle fed a high concentrate diet. Fifty 1- to 2-year-old feedlot cattle fed a high concentrate diet (75% barley) for at least 3 mo (high concentrate diet group) and 15 healthy feedlot cattle of similar ages (control group) that were fed a low concentrate diet (30% barley) were used. Rumen fluid samples were obtained by rumenocentesis and their pH was determined with a portable pH meter. Blood samples taken from all animals from a jugular vein were used to determine erythrocyte transketolase enzyme activity, and hence thiamine pyrophosphate (TPP) effect. Odor and mean pH values of ruminal fluid samples from the high concentrate diet and control group were acidic (pH 5.3) and aromatic (pH 6.1), respectively. The mean TPP effect % in the high concentrate diet group (47.2 ± 3.2) was significantly higher than in the control group (19.53 ± 2.5) (P < 0.001). The study provides evidence of a TPP effect in feedlot cattle fed a high concentrate diet.

[A case of thiamine deficiency with psychotic symptoms--blood concentration of thiamine and response to therapy]

We report the case of a 63-year-old woman with thiamine deficiency who showed auditory hallucinations, a delusion of persecution, catatonic stupor, and catalepsy but no neurological symptoms including oculomotor or gait disturbance. Brain MRI did not show high-intensity T2 signals in regions including the thalami, mamillary bodies, or periaqueductal area. Her thiamine concentration was 19 ng/mL, only slightly less than the reference range of 20-50 ng/mL. Her psychosis was unresponsive to antipsychotics or electroconvulsive therapy, but was ameliorated by repetitive intravenous thiamine administrations at 100-200 mg per day. However, one month after completing intravenous treatment, her psychosis recurred, even though she was given 150 mg of thiamine per day orally and her blood concentration of thiamine was maintained at far higher than the reference range. Again, intravenous thiamine administration was necessary to ameliorate her symptoms. The present patient indicates that the possibility of thiamine deficiency should be considered in cases of psychosis without neurological disturbance and high-intensity T2 MRI lesions. Also, this case suggests that a high blood thiamine concentration does not necessarily correspond to sufficient thiamine levels in the brain. Based on this, we must reconsider the importance of a high dose of thiamine administration as a therapy for thiamine deficiency. The validity of the reference range of the thiamine concentration, 20-50 ng/mL, is critically reviewed.

Gizzard shad thiaminase activity and its effect on the thiamine status of captive American alligators Alligator mississippiensis

Adult mortality and low egg hatch rate were observed among American alligators Alligator mississippiensis in Lake Griffin, Florida, between 1998 and 2003. Previous studies show that the alligator mortality is due to neurological impairment associated with thiamine (vitamin Bt) deficiency. This study determined the rate of thiaminase activity in gizzard shad Dorosoma cepedianum, a fish often eaten by alligators, and examined the thiamine status of captive adult alligators fed only gizzard shad. We found that the thiaminase activity of gizzard shad in Lake Griffin is 16,409 +/- 2,121 pmol/g/min (mean +/- 2SEs). This high rate of thiaminase activity was present in most months and across a wide range of shad sizes. Seven alligators were captured in the wild from Lake Griffin and Lake Woodruff, held in captivity, and fed gizzard shad. We monitored blood and muscle thiamine levels throughout the experiment and liver thiamine at the end. Over a period of 6-12 months, all of the alligators maintained weight but blood and muscle thiamine levels decreased to 25-50% of the original (healthy) values. Three animals with the greatest reduction in thiamine died, demonstrating mobility impairment and neural histopathology similar to those seen in wild alligators in Lake Griffin. Two alligators were fed shad for 10 months but then treated with thiamine. These animals showed a reduction in thiamine while eating shad, but treatment restored their thiamine levels to the initial values, which were comparable to those of normal wild Lake Griffin alligators. We demonstrated that thiamine deficiency can be induced by a diet of gizzard shad and cause neurological signs and death in alligators in captivity. We conclude that the thiaminase activity in gizzard shad is high enough to cause thiamine deficiency in wild alligators when shad are a major part of their diet.

Characteristics of thiamin and its relevance to the management of heart failure

Heart failure (HF) is a major public health problem in the United States that puts a significant burden on both patients and the healthcare system. The prevalence of malnutrition in HF patients is well-known and correlates with a dramatic decline in quality of life and disease progression, and is associated with high morbidity and mortality rates. The implication of HF on micronutrient status is underrecognized in the quest to offer "best practice" medical, device, and surgical interventions to this population. The micronutrient thiamin is of particular interest in the management of HF for several reasons: (a) HF is a disease of the elderly whose micronutrient status is in need of attention; (b) HF patients tend to have inadequate nutrient intake, which has been associated with thiamin deficiency; (c) thiamin deficiency (wet beriberi) impairs cardiac performance and can mimic the signs and symptoms of HF thereby potentially exacerbating the underlying disease; (d) use of loop diuretics to manage fluid and sodium imbalances associated with HF may cause the hyperexcretion of thiamin, thereby increasing the risk of deficiency; and (e) the prevention of thiamin deficiency should be a routine component in the overall management of this disease.

A preliminary study of thiamine status in northeastern Thai children with acute diarrhea

This study is a preliminary determination of thiamine status in children with diarrhea and metabolic acidosis admitted to hospital. Children with diarrhea (N = 14; age 2 m-6 yr) were divided into 2 groups according to anion gap type; group 1 (21.4%) with a normal anion gap (5.5 +/- 5.2 mmol/l) and group 2 (78.6%) with a wide anion gap (21.2 +/- 5.2 mmol/l). Blood was taken on the day of admission to determine thiamine and lactate levels. Sixty-six point seven percent of patients in group 1 had a normal lactate level (1.5 +/- 0.8 mmol/l) and 33.3% had a high lactate level (2.2 mmol/l); none had thiamine deficiency (TPPE < 20%). High lactate (3.5 +/- 1.4 mmol/l) was found in 54.5% of group 2 and thiamine deficiency was observed in 18.2% of this group. In conclusion, no thiamine deficiency was noted in patients with normal anion gap, but thiamine deficiency was not uncommon in patients with a wide anion gap, regardless of lactic acidosis.

High prevalence of low plasma thiamine concentration in diabetes linked to a marker of vascular disease

AIMS/HYPOTHESIS

To assess thiamine status by analysis of plasma, erythrocytes and urine in type 1 and type 2 diabetic patients and links to markers of vascular dysfunction.

METHODS

Diabetic patients (26 type 1 and 48 type 2) with and without microalbuminuria and 20 normal healthy control volunteers were recruited. Erythrocyte activity of transketolase, the concentrations of thiamine and related phosphorylated metabolites in plasma, erythrocytes and urine, and markers of metabolic control and vascular dysfunction were determined.

RESULTS

Plasma thiamine concentration was decreased 76% in type 1 diabetic patients and 75% in type 2 diabetic patients: normal volunteers 64.1 (95% CI 58.5-69.7) nmol/l, type 1 diabetes 15.3 (95% CI 11.5-19.1) nmol/l, p < 0.001, and type 2 diabetes 16.3 (95% CI 13.0-9.6) nmol/l, p < 0.001. Renal clearance of thiamine was increased 24-fold in type 1 diabetic patients and 16-fold in type 2 diabetic patients. Plasma thiamine concentration correlated negatively with renal clearance of thiamine (r = -0.531, p < 0.001) and fractional excretion of thiamine (r = -0.616, p < 0.001). Erythrocyte transketolase activity correlated negatively with urinary albumin excretion (r = -0.232, p < 0.05). Thiamine transporter protein contents of erythrocyte membranes of type 1 and type 2 diabetic patients were increased. Plasma thiamine concentration and urinary excretion of thiamine correlated negatively with soluble vascular adhesion molecule-1 (r = -0.246, p < 0.05, and -0.311, p < 0.01, respectively).

CONCLUSIONS/INTERPRETATION

Low plasma thiamine concentration is prevalent in patients with type 1 and type 2 diabetes, associated with increased thiamine clearance. The conventional assessment of thiamine status was masked by increased thiamine transporter content of erythrocytes.

Presumed primary thiamine deficiency in a young African lion (Panthera leo)

A 1-yr-old intact male African lion (Panthera leo) fed only beef muscle meat was evaluated for episodes of hypermetric ataxia, generalized weakness and tonic-clonic front limb movements. A hemogram, biochemical profile, blood lead, electrocardiogram, survey radiographs, and brain computed tomography were normal. Cerebral spinal fluid analyses suggested mild inflammation. Acetylcholine receptor antibody and serologic tests for all infectious agents tested were negative. Clinical signs resolved completely 9 days after instituting oral thiamine (3 mg/kg/day) and a completely nutritional diet. This lion's pretreatment thiamine blood value (11 nmol/L) was markedly lower than that of a healthy lion (191 nmol/L) and a proposed reference range for adult African lions (160-350 nmol/L). The lion remained clinically normal 2 yr later when his blood thiamine value was 340 nmol/L. African lions can develop clinical primary thiamine deficiency and may respond favorably when thiamine treatment and adequate diet are instituted prior to irreversible neuronal necrosis.

Thiamin and riboflavin status of Taiwanese elementary schoolchildren

In The Nutrition and Health Survey of Taiwan Elementary School Children (NAHSIT Children 2001~2002), erythrocyte activity coefficients of transketolase (ETKAC) and glutathione reductase (EGRAC) were chosen as indices for assessing the functional status of thiamin and riboflavin nutriture. Mean values of the ETKAC for boys and girls, both of which were in a normal range, were 1.07+/-0.00 and 1.06+/-0.01, respectively. The respective prevalence rates of marginal and deficient thiamin states were 10.4% and 7.8% for boys and 9.3% and 7.3% for girls. Mean values of the EGRAC were 1.18+/-0.00 for boys and 1.19+/-0.01 for girls, both of which showed an increasing trend with age. The respective rates of marginal and deficient riboflavin states were as high as 32.5% and 3.5% for boys and 35.9% and 4.5% for girls. The marginal and deficient riboflavin statuses of Taiwanese schoolchildren were associated with a low frequency of dairy food consumption and an elevated risk of anemia.

Fatal metabolic acidosis caused by thiamine deficiency

Acute thiamine deficiency, an uncommon cause of hemodynamic instability in Western countries, may be manifested by acute heart failure and neurological deficits. Severe metabolic acidosis is one of its least recognized features. We present a report of foreign workers who complained of weakness and lower limb edema and were found to have acute thiamine deficiency. One died of refractory metabolic acidosis and shock, and the diagnosis was reached post mortem. Thiamine deficiency should be considered in every case of severe lactic acidosis without an obvious cause, especially in high-risk populations (malnourished, alcoholics, Far-East workers, etc). Whenever it is suspected, empiric treatment with thiamine should be initiated immediately. Physicians who care for populations at risk should be familiar with the clinical spectrum of nutritional deficits, and monitor the nutritional habits of these patients carefully. The treatment is inexpensive and devoid of adverse effects. Moreover, delaying thiamine administration in patients with deficiency may cause severe life-threatening metabolic acidosis and affect recovery. The prophylactic use of thiamine in a high-risk population, even before blood levels are received, may be cost effective.

EVALUATION OF A CLINICAL SCREENING INSTRUMENT TO IDENTIFY STATES OF THIAMINE DEFICIENCY IN INPATIENTS WITH SEVERE ALCOHOL DEPENDENCE SYNDROME

AIMS

To develop a Thiamine Deficiency Questionnaire (TDQ), and to assess its reliability in the identification of Thiamine deficiency, in patients with severe alcohol dependence.

METHODS

58 severely alcohol dependent patients underwent socio-demographic, medical, psychiatric, and alcohol use assessment, including administration of the Thiamine Deficiency Questionnaire (TDQ). The Red Blood Cell Thiamine Pyrophosphate concentration provided the 'gold standard' to test the validity of the instrument. Univariate 2 x 2 diagnostic test tables and multivariate analysis were performed.

RESULTS

A set of eight questionnaire items had an overall predictive power of 73.7%. Two of these were highly specific: 'missed meals due to lack of funds', and the clinical co-occurrence of medical conditions potentially related to poor nutrition. The Michigan Alcohol Screening Test and serum gamma glutamyl transferase were moderately predictive.

CONCLUSIONS

Screening that combines socio-demographic, clinical and biological factors, and/or standardized questionnaires, could improve early recognition of thiamine deficiency.

[Thiamine deficiency polyneuropathy after gastrectomy associated with high level of serum vascular endothelial growth factor (VEGF). A case report]

We report a 66-year-old man who developed vitamin B1 deficiency polyneuropathy long after a gastrectomy. After a preceding bronchial infection, the patient noticed numbness and weakness in his extremities, followed by generalized edema and exertional dyspnea. He had undergone subtotal gastrectomy due to duodenal ulcer at age 19. His daily oral intake of food was normal without any alcoholic abuse. He was admitted to our hospital with rapidly progressive gait disturbance due to muscle weakness, and sensory disturbance. Neurological examination showed peripheral polyneuropathy with distal dominant muscular weakness and sensory disturbance. Chest X-ray film showed marked cardiomegaly and pleural effusion. Nerve conduction studies showed decreases in the action potentials of both the motor and sensory nerves, with the sensory nerves being more severely affected than the motor nerves. Sural nerve biopsy demonstrated severe axonal degeneration without any inflammatory change. The blood concentration of thiamine (vitamin B1) was slightly decreased below the normal range (19 ng/ml; normal, 20-50), and the serum vascular endothelial growth factor (VEGF) was high (890 pg/ml; normal < 200 pg/ml). Intravenous administration of vitamin B1 (50 mg per day) dramatically improved his symptoms in a few days and the level of VEGF returned to nearly normal. In this gastrectomized patient many years ago, vitamin B1 deficiency neuropathy is warranted in view of a prompt response to thiamine administration. This case suggests that VEGF is involved in the pathogenesis of vitamin B1 deficiency polyneuropathy.

Thiamin, selenium, and copper levels in patients with idiopathic dilated cardiomyopathy taking diuretics

OBJECTIVE

To analyze the association of thiamin, selenium, and copper serum levels with cardiac function in patients with idiopathic dilated cardiomyopathy using diuretics, and also to compare them with levels in control patients with no evidence of disease.

METHODS

The study comprised 30 patients with heart disease and 30 healthy control individuals. Thiamin was analyzed by measuring the activity of erythrocytic transketolase and the effect of thiamin pyrophosphate. Selenium and copper serum levels were measured by hydride generation and flame atomic absorption spectrophotometry, respectively.

RESULTS

Thiamin deficiency was observed in 10% of the control individuals and in 33% of the patients with heart disease (p=0.02). The mean selenium and copper serum levels in control individuals and patients with heart disease were, respectively, 73.2+/-9.9 microg/L (56.5 to 94.5 microg/L) and 72.3+/-14.3 microg/L (35.5 to 94 microg/L) (p=0.77); 1.1+/-0.4 mg/L (0.6 to 1.8 mg/L) and 1.2+/- 0.4 mg/L (0.6 to 2.2 mg/L) (p=0.27). No association between the levels of these nutrients and cardiac function was observed.

CONCLUSION

Thiamin deficiency was significantly more frequent in patients with heart disease. No significant difference was observed between the mean selenium and copper serum levels in control individuals and in patients with heart disease. The results suggest possible benefits with thiamin replacement in patients taking diuretics.

Vitamin profile of 563 gravidas during trimesters of pregnancy

OBJECTIVE

Gestation imposes metabolic stress on the mother which heightens as pregnancy progresses. The need for quantifying circulating vitamins is important for identifying pitfalls in metabolic imbalance and nutritional status. For this reason we wanted to analyze blood vitamin concentrations of B12, thiamin, biotin, pantothenate, B6, niacin, riboflavin, folate, vitamins A, C, E and total carotenes to determine if imbalances occur during the trimesters of pregnancy.

METHODS

We randomly selected 563 gravidas who volunteered for this study from the obstetrical clinic of New Jersey Medical School; 132 were in 1st trimester, 198 were in 2nd trimester, and 233 were in 3rd trimester. All were healthy, taking a good diet and supplemented with vitamins. Blood, from an antecubital vein, was analyzed for thiamin, biotin, B12, B6, pantothenate, riboflavin, nicotinate, folates, vitamins A, E, C and total carotenes. Gravidas were classified as being normovitaminemic, hypervitaminemic or hypovitaminemic compared with blood vitamins seen in healthy non-pregnant, non-vitamin supplemented women.

RESULT

Hypervitaminemic levels of folate, biotin, pantothenate and riboflavin were found during any trimester of pregnancy due to vitamin supplementation. Despite the vitamin supplementation, a high percent of vitamin A, B6, niacin. thiamin and B 12 hypovitaminemia was noted during pregnancy trimesters. An especially high percentage of niacin deficiency was seen during the 1st trimester; it worsened in later trimesters; B12 deficits increased during the late trimesters. Combination deficits of niacin, thiamin, vitamins A, B6, B12 were noted in each of the trimesters.

CONCLUSIONS

Despite vitamin supplementation, a vitamin profile of pregnancy indicates that vitamin deficits exist during the trimesters. Also, combination hypovitaminemias of deficient vitamins were noted; this indicates that a vitamin deficit during pregnancy does not occur in isolation.

Postpartum thiamine deficiency in a Karen displaced population

BACKGROUND

Before its recognition, infantile beriberi was the leading cause of infant death in camps for displaced persons of the Karen ethnic minority on Thailand's western border.

OBJECTIVE

This study aimed to document thiamine status in the peripartum period to examine the current supplementation program and the correlation between the clinical manifestations of thiamine deficiency and a biochemical measure of thiamine status.

DESIGN

Women were enrolled prospectively at 30 wk of gestation and were followed up weekly until delivery and at 3 mo postpartum. Thiamine supplementation during pregnancy was based on patient symptoms.

RESULTS

At 3 mo postpartum, thiamine deficiency reflected by an erythrocyte transketolase activity (ETKA) > or = 1.20% was found in 57.7% (15/26) of mothers, 26.9% (7/26) of whom had severe deficiency (ETKA > 1.25%). No significant associations between ETKA and putative maternal symptoms or use of thiamine supplements were found.

CONCLUSIONS

Biochemical postpartum thiamine deficiency is still common in Karen refugee women. This situation may be improved by educating lactating women to reduce their consumption of thiaminase-containing foods and by implementing an effective thiamine supplementation program.

Postgastrectomy polyneuropathy with thiamine deficiency

OBJECTIVE

Polyneuropathy has been reported after gastrectomy performed to treat various lesions. Although thiamine deficiency is a possible cause of this neuropathy, the pathogenesis still remains to be clarified. Seventeen patients with peripheral neuropathy with thiamine deficiency after gastrectomy are described.

METHODS

Seventeen patients with polyneuropathy after gastrectomy accompanied by thiamine deficiency were selected. Patients were restricted to those with total or subtotal gastric resection to treat ulcer or neoplasm. Patients who had undergone operations to treat morbid obesity were excluded.

RESULTS

Intervals between the operation and onset of neuropathy varied from 2 months to 39 years. Most patients did not seem malnourished. Serum concentrations of B vitamins other than thiamine were nearly normal. Symmetric motor-sensory polyneuropathy, predominantly involving the lower limbs, had progressed over intervals varying from 3 days to 8 years. Relative degrees of motor and sensory impairment also varied extensively. Some cases that progressed rapidly mimicked Guillain-Barré syndrome. Electrophysiological and pathological findings were those of axonal neuropathy. Substantial functional recovery from polyneuropathy was seen in most patients by 3 to 6 months after initiating thiamine supplementation. Motor recovery was better than sensory recovery.

CONCLUSIONS

Various symptoms were seen in patients with postgastrectomy neuropathy. Thiamine deficiency should be considered in the differential diagnosis of motor-sensory polyneuropathy after gastrectomy.

Painful alcoholic polyneuropathy with predominant small-fiber loss and normal thiamine status

BACKGROUND

Although polyneuropathy related to chronic alcoholism has been reported frequently, its clinical features and pathogenesis remain to be clarified.

OBJECTIVE

To determine the clinicopathologic features and pathogenesis of alcoholic polyneuropathy associated with pain in patients with normal thiamine status, particularly in comparison to beriberi neuropathy.

PATIENTS AND METHODS

Clinical, electrophysiologic, and histopathologic findings were assessed in 18 patients with painful alcoholic polyneuropathy and normal thiamine status.

RESULTS

Symmetric sensory-dominant polyneuropathy predominantly involving the lower limbs was the major clinical pattern. Painful sensations with or without burning quality represented the initial and major symptom. Progression of symptoms usually was gradual, continuing over months or years. Electrophysiologic and pathologic findings mainly indicated an axonal neuropathy. Densities of small myelinated fibers and unmyelinated fibers were more severely reduced than the density of large myelinated fibers, except in patients with a long history of neuropathic symptoms and marked axonal sprouting.

CONCLUSIONS

The clinicopathologic features of painful symptoms and small axon loss are distinct from those of beriberi neuropathy. Sensory-dominant involvement with prominent neuropathic pain is characteristic of alcoholic neuropathy when thiamine deficiency is not involved, supporting the view of direct neurotoxic effect by alcohol or its metabolites.

Thiamin status of gravidas treated for gestational diabetes mellitus compared to their neonates at parturition

Since thiamin plays a role in glucose metabolism we wanted to know if blood thiamin influx from gravida to neonate was influenced by treatment of gravidas having gestational diabetes mellitus (GDM). In this study we found thiamin hypovitaminemia in 19% of the 77 pregnancies despite vitamin supplementation and treatment for GDM; neonates born to mothers with hypovitaminemia were also thiamin hypovitaminemic. All neonatal blood had significantly higher thiamin concentration than gravidas. Indeed, cord blood from neonates born to mothers treated with insulin for GDM had significantly higher thiamin concentration than other neonates in the study. A significant weight depression was noted in neonates born to treated GDM mothers. Healthy gravidas giving birth to macrosomia neonates, had significant thiamin hypovitaminosis, but only macrosomic neonates of treated diabetic mothers had significantly depressed blood thiamin concentrations. We noted that subclinical thiamin hypovitaminemia is prominent during pregnancy despite vitamin supplementation. Perhaps increased thiamin supplementation during pregnancy seems warranted to avoid metabolic stress in mother and fetus due to thiamin hypovitaminemia.

The relationship between thiamine deficiency and performance of a learning task in rats

We have been investigating the relationship between learning and thiamine. Electrical stimulation of mesencephalic periaqueductal gray matter (PAG) is known to have an aversive effect and elicits spontaneous instrumental escape behavior. We taught rats to press a lever to escape from the pain of electrical stimulation by learning to turn a switch off. Then we examined the relationship between learning and the thiamine concentration in various portions of the brain. (1) One group of rats was given a normal diet and another group was given a thiamine-deficient diet which contained half of the amount of thiamine present in the normal diet. We measured the response time required for each rat to react by moving after an electrical impulse was applied, and the running time during which the rat was moving from the starting point to the end point to press a lever. The rats that were fed the thiamine-deficient diet showed a slower response time and a longer running time than the rats fed the normal diet. (2) We divided the rats fed the normal diet into two groups, one group trained to switch off a lever and the other group not trained for such a task. We found that the thiamine concentration in the blood of the rats in the trained group was significantly higher than that in the group without training.

Lactic acidosis caused by thiamine deficiency in a pregnant alcoholic patient

BACKGROUND

Metabolic acidosis from accumulation of lactic acid is a relatively common condition, whereas its causation by thiamine deficiency is not.

METHODS

We studied a pregnant alcoholic patient who presented with hyperemesis and a high anion gap acidosis.

RESULTS

Lactic acidosis and thiamine deficiency were confirmed. The patient's symptoms and acidosis resolved with thiamine administration.

CONCLUSIONS

Lactic acidosis caused by thiamine deficiency must be suspected when pregnant patients at risk for thiamine deficiency present with a high anion gap acidosis. A large dose of thiamine must be administered immediately.

[Severe lactic acidosis and thiamine deficiency during parenteral nutrition in a child]

We report the case of a leukemic child treated with chemotherapy and parenteral nutrition for three weeks, who developed a severe lactic acidosis. Clinical features included both digestive and neurological disorders associated with a moderate cardiovascular collapse. After elimination of a toxic, a neoplastic or a septic cause, a thiamin (or vitamin B1) deficiency was suspected because of the lack of vitamin supply to parenteral nutrition. Intravenous administration of thiamin rapidly controlled lactic and clinical features. The diagnosis was confirmed by a low plasmatic concentration of thiamin. Thiamin deficiency must be suspected in case of severe lactic acidosis during parenteral nutrition and systematically prevented by supply of vitamins.

Proposed standard for human blood vitamin B1 value using HPLC. The Committee for Vitamin Laboratory Standards, Japan

Standard reference ranges for all laboratory test values are mandatory. This study was designed to establish a reference range for blood vitamin B1 levels, since the normal range has not been determined in the Japanese population. We founded the Japan Committee for Vitamin Laboratory Standards, which was incorporated with the Vitamin Society of Japan and the Japanese Society of Nutrition and Food Science. We standardized whole blood vitamin B1 levels using three HPLC techniques (post-column reverse-phase HPLC, pre-column reverse-phase HPLC, and precolumn GP-HPLC). The reference range was obtained in 54 volunteers administered a 1,800 kcal diet with 2 mg of vitamin B1 (1.74 mg measured) daily to avoid marginal vitamin B1 deficiency in the population. The range for each assay was 26-47, 28-51, and 28-56 ng/ml, respectively. Our data suggest that 26-28 ng/ml is the lower limit of normal for whole blood vitamin B1, but further studies in a larger population are needed in order to obtain more definitive results.

[The thiamine index as an integral indicator of the body allowance of vitamin B1]

One of the most wide-spread methods of evaluation of thiamine content in the body is determination of the activity of the thiamine pyrophosphate-dependent enzyme--transketolase--and so-called TPP-effect (the quantitative measure of unsaturation of transketolase with coenzyme). Absence of distinct correlation between the parameters in a number of cases calls for a search for the integral coefficient less dependent on the original dynamics of the given markers. Thus, we propose to use the thiamine index calculated by means of division of transketolase activity index expressed in absolute units by TPP-effect index expressed in relative units. The examples of thiamine index calculation and peculiarities of its interpretation with consideration of dynamic state of chronic alcoholics in abstinence and of patients with acute alcohol psychoses are shown.

Plasma thiamine deficiency associated with Alzheimer's disease but not Parkinson's disease

In this study we compared plasma and erythrocyte thiamine levels in a group of patients with idiopathic Parkinson's Disease (iPD) to a group of patients with probable Alzheimer's Disease (pAD). pAD patients had significantly lower plasma thiamine levels (raw and z-score) than iPD patients. A significantly higher number of pAD patients had plasma thiamine deficiencies than iPD patients. The demographics of our patient groups were similar to those reported by other investigators, making age, sex and nutritional status unlikely explanations for our findings. These results suggest that plasma thiamine deficiency is associated with pAD but not with iPD.

Protection against cardiovascular collapse in an alcoholic patient with thiamine deficiency by concomitant alcoholic ketoacidosis

Hyperlactataemia due to thiamine deficiency has so far only been reported in the setting of full-blown cardiovascular beriberi with congestive heart failure and systemic vasodilatation. Poor tissue oxygenation and impaired lactate clearance by the liver are generally accepted as underlying causes of the elevated lactate levels. We present an alcoholic patient with thiamine deficiency-induced hyperlactataemia and accompanying alcoholic ketoacidosis, who did not display the circulatory disturbances that are characteristic of cardiovascular beriberi. The hypothesis will be presented that the concomitant presence of alcoholic ketoacidosis has prevented haemodynamic deterioration. Putative mechanisms that could explain such an effect are discussed in detail, with special reference to the role of acetyl-CoA and adenosine.

[Influence of lead on metabolism of vitamins B group in alimentary iron deficient rats]

Experimentally induced lead poisoning especially under simultaneous iron deficit leads to the development of secondary thiamine insufficiency. Erythrocyte riboflavin content and erythrocyte glutathion reductase and aspartate aminotransferase activities have been demonstrated to be increased. Lead treatment is accompanied with the increase of urinary excretion of riboflavin, 4-pyridoxic acid and 1-vtthylnicotinamide in rats fed with adequate diet. Thus lead intoxication and iron deficiency influence vitamin B group metabolism.

Recurrent aphthous stomatitis and thiamine deficiency

Recurrent aphthous stomatitis is a disease of unknown cause. To examine whether thiamine (vitamin B1) deficiency is associated with recurrent aphthous stomatitis, we studied vitamin B1 levels in 70 patients with recurrent aphthous stomatitis and in 50 members of a control group. The vitamin B1 level was determined as thiamine pyrophosphate effect on transketolase activity in red blood cell lysates. Low levels of vitamin B1 were detected in 49 patients but in only two members of the control group (p < 0.0001). These low levels were not associated with patient age, sex, or underlying disease causing recurrent aphthous stomatitis. Our finding suggests an association between thiamine deficiency and recurrent aphthous stomatitis.

Thiamin, riboflavin and vitamin B6: impact of restricted intake on physical performance in man

OBJECTIVE

A combined marginally deficient status of thiamin, riboflavin, vitamin B6 and vitamin C may affect physical performance, but the relative contribution of each vitamin can only be speculated. In a previous study we did not find any effect of restricted intake of vitamin C individually. Therefore, the functional effect of restriction of thiamin, riboflavin or vitamin B6, individually or in conjunction, was investigated.

METHODS

A double-blind, 2 x 2 x 2 complete factorial experiment on the effects of thiamin, riboflavin and vitamin B6 restriction on physical performance was executed with 24 healthy men. During 11 weeks of low vitamin intake, the subjects were given a daily diet of regular food products providing no more than 55% of the Dutch Recommended Dietary Allowances (RDA) for thiamin, riboflavin and vitamin B6. Other vitamins were supplemented at twice the RDA level.

RESULTS

In vitamin-restricted subjects, blood vitamin levels, erythrocytic enzyme activities and urinary vitamin excretion decreased and in vitro erythrocytic enzyme stimulation increased. Short-time vitamin restriction had no harmful effects on health. A significant overall decrease was observed in aerobic power (VO2-max; 11.6%), onset of blood lactate accumulation (OBLA; 7.0%) and oxygen consumption at this power output (VO2-OBLA; 12.0%), peak power (9.3%), mean power (6.9%) and related variables (p < 0.01). However, the observed performance decrements could not be attributed to marginal deficiency for any of the vitamins studied.

CONCLUSION

The absence of vitamin-specific effects on performance decrements due to thiamin, riboflavin and vitamin B6 restriction suggests quantitatively similar but non-additive effects of these B-vitamins on mitochondrial metabolism.

Thiamine deficiency in patients admitted to a palliative care unit

This study looks at the clinical and thiamine status of 50 terminally ill patients who were admitted to a palliative care unit. Thiamine levels were found to be abnormally low in 28% of the patients and borderline in a further 36%. Cognitive impairment, as measured by the mini-metal state examination (MMSE) of Folstein, Folstein and McHugh, was present in 68% of those tested and a significant correlation was found between the MMSE status and thiamine levels.

[Case-control study on intrauterine growth retardation and vitamin nutritional status in late pregnancy]

Ninety-seven cases of pregnant women with intrauterine growth retardation (IUGR) and 133 controls were investigated on their dietary intake and blood vitamin levels in late pregnancy. Results showed insufficient calorie and protein intake, deficiency in calcium and vitamin B2, and low intake of vitamins A and B1 in pregnant women with IUGR. Their serum level of vitamin E was only half as that in controls (P < 0.01). Mothers' serum level of vitamin E correlated positively to several indicators reflecting infant growth with multiple stepwise regression analysis. There was no significant difference of activity of erythrocytic transketonas activity (TPP%) and activity coefficient (AC) of glutathione reductase between the two groups. It suggested pregnant women in both groups suffered from deficiency in thiamine and riboflavin (TPP% > 16%, AC > 1.2).