Neurological, Psychiatric, and Biochemical Aspects of Thiamine Deficiency in Children and Adults.

Thiamine (vitamin B1) is an essential nutrient that serves as a cofactor for a number of enzymes, mostly with mitochondrial localization. Some thiamine-dependent enzymes are involved in energy metabolism and biosynthesis of nucleic acids whereas others are part of the antioxidant machinery. The brain is highly vulnerable to thiamine deficiency due to its heavy reliance on mitochondrial ATP production. This is more evident during rapid growth (i.e., perinatal periods and children) in which thiamine deficiency is commonly associated with either malnutrition or genetic defects. Thiamine deficiency contributes to a number of conditions spanning from mild neurological and psychiatric symptoms (confusion, reduced memory, and sleep disturbances) to severe encephalopathy, ataxia, congestive heart failure, muscle atrophy, and even death. This review discusses the current knowledge on thiamine deficiency and associated morbidity of neurological and psychiatric disorders, with special emphasis on the pediatric population, as well as the putative beneficial effect of thiamine supplementation in autism spectrum disorder (ASD) and other neurological conditions

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

Erythrocyte Transketolase Activity, Markers of Cardiac Dysfunction and the Diagnosis of Infantile Beriberi

Infantile beriberi, or clinical thiamin (vitamin B1) deficiency in infants, is a forgotten disease in Asia, where ∼100 years ago it was a major public health problem. Children aged ∼2–3 months present in cardiac failure but usually rapidly improve if given thiamin injections. It remains relatively common in Vientiane, Lao PDR (Laos) probably because of prolonged intra- and post-partum maternal food avoidance behaviours. There has been very little recent research on the best diagnostic techniques. We conducted a case control study of 47 infants with beriberi and age-matched afebrile and febrile controls in Vientiane. The conventional measures of thiamin deficiency, basal and activated erythrocyte transketolase activities (ETK) and activation (α) coefficients, were assayed along with three markers of cardiac dysfunction - plasma brain natriuretic peptide, N-terminal pro-brain natriuretic peptide, and troponin T. Basal ETK was a better biochemical marker of infantile beriberi than the activation coefficient. Raised plasma troponin T may be a useful indicator of infantile beriberi in babies at risk and in the absence of other evident causes

Scientific opinion on dietary reference values for thiamin

Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) derived dietary reference values (DRVs) for thiamin (vitamin B1). The Panel considers that data from depletion\u2013repletion studies in adults on the amount of dietary thiamin intake associated with the erythrocyte transketolase activity coefficient (\u3b1ETK) < 1.15, generally considered to reflect an adequate thiamin status, or with the restoration of normal (baseline) erythrocyte transketolase activity, without a sharp increase in urinary thiamin excretion, can be used to estimate thiamin requirement. In the absence of new scientific evidence, the Panel endorses the average requirement (AR) of 0.072 mg/MJ (0.3 mg/1,000 kcal) for all adults proposed by the Scientific Committee for Food (SCF) in 1993 on the basis of one depletion\u2013repletion study, in which both \u3b1ETK and urinary thiamin excretion were measured. Results from other depletion\u2013repletion studies are in agreement with this value. The Panel agrees on the coefficient of variation of 20% used by the SCF to cover uncertainties related to distribution of thiamin requirements in the general population, and endorses the population reference intake (PRI) of 0.1 mg/MJ (0.4 mg/1,000 kcal) set by the SCF for all adults. The same AR and PRI as for adults, expressed in mg/MJ, are proposed for infants aged 7\u201311 months, children aged 1 to < 18 years, and during pregnancy and lactation, under the assumption that the relationship between thiamin requirement and energy requirement is the same in all population groups