Thiamine deficiency and cardiac dysfunction in Cambodian infants.

OBJECTIVES: 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. STUDY DESIGN: 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. RESULTS: 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 21 nmol/L) had right ventricular enlargement and elevated NT-proBNP levels that improved dramatically by 48 hours after thiamine administration. CONCLUSION: 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.

Thiamine pharmacokinetics in Cambodian mothers and their breastfed infants.

BACKGROUND: Thiamine deficiency is common in parts of Asia and causes beriberi. Pharmacokinetics of thiamine in deficient populations are unknown. OBJECTIVE: We characterized thiamine pharmacokinetics in Cambodian mothers and their breastfed infants. DESIGN: Total plasma thiamine, whole-blood thiamine diphosphate (TDP), and breast milk total thiamine were measured in 16 healthy Cambodian mothers and their infants before and after mothers received oral thiamine hydrochloride (100 mg for 5 d). Assays were also performed in 16 healthy American mothers. RESULTS: On day 1, Cambodian mothers were thiamine deficient, with median (range) total plasma thiamine and TDP concentrations of 2.4 nmol/L (0-4.4 nmol/L) and 58.0 nmol/L (27-98 nmol/L), respectively. After a single oral dose, the mean ± SD maximal concentration of thiamine and net area under the thiamine concentration-time curve were 73.4 ± 45.6 nmol/L and 465 ± 241 h · nmol ∙ L⁻¹. Day 6 median maternal total plasma thiamine and TDP concentrations were normal [18.6 nmol/L (13.4-25.3 nmol/L) and 76.5 nmol/L (48-107 nmol/L), respectively; P ≤ 0.001 compared with day 1]. Median Cambodian total breast milk thiamine concentration increased from 180 nmol/L (85-359 nmol/L) on day 1 to 403 nmol/L (314-415 nmol/L) on day 2 and 503 nmol/L (360-808 nmol/L) on day 6; the corresponding American breast milk value was 500 nmol/L (114-622 nmol/L). Median Cambodian infant total plasma thiamine and TDP concentrations increased from 3.0 nmol/L (0-7.3 nmol/L) and 38.5 nmol/L (23-57 nmol/L), respectively, on day 1 to 5.6 nmol/L (0-9.7 nmol/L) and 45.5 nmol/L (32-70 nmol/L), respectively, on day 6. CONCLUSIONS: Thiamine-deficient Cambodian mothers effectively absorb oral thiamine, with sharp increases in breast milk thiamine concentrations, but their breastfed infants remain thiamine deficient after 5 d of maternal supplementation. Longer-term maternal supplementation may be necessary to correct thiamine deficiency in breastfed infants. This trial was registered at clinicaltrials.gov as NCT01864057.

Effect of micronutrient sprinkles on reducing anemia: a cluster-randomized effectiveness trial.

OBJECTIVE: To evaluate the effectiveness of Sprinkles alongside infant and young child feeding (IYCF) education compared with IYCF education alone on anemia, deficiencies in iron, vitamin A, and zinc, and growth in Cambodian infants. DESIGN: Cluster-randomized effectiveness study. SETTING: Cambodian rural health district. PARTICIPANTS: Among 3112 infants aged 6 months, a random subsample (n = 1350) was surveyed at baseline and 6-month intervals to age 24 months. INTERVENTION: Daily micronutrient Sprinkles alongside IYCF education vs IYCF education alone for 6 months from ages 6 to 11 months. MAIN OUTCOME MEASURES: Prevalence of anemia; iron, vitamin A, and zinc deficiencies; and growth via biomarkers and anthropometry. RESULTS: Anemia prevalence (hemoglobin level <11.0 g/dL [to convert to grams per liter, multiply by 10.0]) was reduced in the intervention arm compared with the control arm by 20.6% at 12 months (95% CI, 9.4-30.2; P = .001), and the prevalence of moderate anemia (hemoglobin level <10.0 g/dL) was reduced by 27.1% (95% CI, 21.0-31.8; P < .001). At 12 and 18 months, iron deficiency prevalence was reduced by 23.5% (95% CI, 15.6-29.1; P < .001) and 11.6% (95% CI, 2.6-17.9; P = .02), respectively. The mean serum zinc concentration was increased at 12 months (2.88 µg/dL [to convert to micromoles per liter, multiply by 0.153]; 95% CI, 0.26-5.42; P = .03). There was no statistically significant difference in the prevalence of zinc and vitamin A deficiencies or in growth at any time. CONCLUSIONS: Sprinkles reduced anemia and iron deficiency and increased the mean serum zinc concentration in Cambodian infants. Anemia and zinc effects did not persist beyond the intervention period. TRIAL REGISTRATION anzctr.org.au Identifier: ACTRN12608000069358.

Thiamine deficiency in Cambodian infants with and without beriberi.

OBJECTIVES: To test the hypothesis that heavy metal toxicity and consumption of thiaminase-containing foods predispose to symptomatic thiamine deficiency. STUDY DESIGN: In a case-control study, thiamine diphosphate (TDP) blood concentrations were measured in 27 infants diagnosed with beriberi at a rural clinic, as well as their mothers and healthy Cambodian and American controls. Blood and urine levels of lead, arsenic, cadmium, mercury, and thallium were measured. Local food samples were analyzed for thiaminase activity. RESULTS: Mean TDP level among cases and Cambodian controls was 48 and 56 nmol/L, respectively (P = .08) and was 132 nmol/L in American controls (P < .0001 compared with both Cambodian groups). Mean TDP level of mothers of cases and Cambodian controls was 57 and 57 nmol/L (P = .92), and was 126 nmol/L in American mothers (P < .0001 compared with both Cambodian groups). Cases (but not controls) had lower blood TDP levels than their mothers (P = .02). Infant TDP level decreased with infant age and was positively associated with maternal TDP level. Specific diagnostic criteria for beriberi did not correlate with TDP level. There was no correlation between heavy metal levels and either TDP level or case/control status. No thiaminase activity was observed in food samples. CONCLUSIONS: Thiamine deficiency is endemic among infants and nursing mothers in rural southeastern Cambodia and is often clinically inapparent. Neither heavy metal toxicity nor consumption of thiaminase-containing foods account for thiamine deficiency in this region.