Thiamine deficiency is associated with infant mortality in Northern Laos

Thiamine deficiency might cause infant mortality among ethnic groups in northern Laos, which requires urgent attention such as prevention of thiamine deficiency and nutritional education. It should also focus on at risk Asian populations reporting similar low diversity diets and thiamine intake, thiaminase rich diets and food avoidance during and after pregnancy.

Thiamine (vitamin B1), an important cofactor in metabolism and energy production, is required for the biosynthesis of neurotransmitters and the production of anti-oxidant substances. Diets that are rich in thiaminase or diets that consist of very poor sources of thiamine are the two main causes that lead to thiamine deficiency. Thiamine deficiency has serious and rapid consequences, which can result in illness and death within 2-3 months. Infants that are breastfed by women with deficient thiamine levels could suffer thiamine deficiency. Cardiac failure related to thiamine deficiency has been described in Japanese teenagers consuming sweet carbonated soft drinks, instant noodles and polished rice. In developing countries such as Laos, traditional food avoidance during the postpartum period, nutritional habits and the high rate of childhood stunting all could be related to thiamine deficiency. There is evidence infantile thiamine deficiency in urban Laos (Vientiane), but data from outside Vientiane to justify the recommendation of thiamine supplementation in the Lao national nutrition strategy is insufficient. Therefore, this study was conducted to investigate if the same cases of infant and maternal thiamine deficiency exist in the Luang Namtha province of Laos.

First, a retrospective survey of all infants with a diagnosis of thiamine deficiency admitted to the 5 hospitals in the province was conducted. Second, all infants with cardiac failure at Luang Namtha Hospital were recorded in a prospective survey. Third, from the previous 2 surveys, all mothers with infants (1-6 months) living in 22 villages of the thiamine deficiency patients’ origin were investigated. Infant mortality was estimated by verbal autopsy.

The retrospective study identified 54 infants that were admitted with acute severe cardiac failure. 49 had their symptoms ameliorated after the administration of parenteral thiamine. 3 died and 2 were lost in follow-up. In the prospective study, the four infants that presented thiamine deficiency at Luang Namtha Provincial hospital recovered after a thiamine injection. In the 22 villages, of 468 live born infants, 50 died during the first year. A peak of mortality (36 deaths) was reported between 1 and 3 months. Verbal autopsy suggested that 17 deaths were due to suspected infantile thiamine deficiency. Of 127 mothers, 47.2% reported edema and paresthesia as well as a positive squat test during pregnancy; 98.4% respected postpartum food avoidance and all ate polished rice. Of 127 infants, 1.6% had probable thiamine deficiency; 6.8% possible deficiency.

Based on the results of these surveys, it is probable that thiamine deficiency makes a large contribution to the rate of infant mortality among ethnic groups in northern Laos. This requires urgent attention such as prevention of thiamine deficiency and nutritional education. Future strategies should also focus on at risk Asian populations reporting similar low diversity diets and thiamine intake, thiaminase rich diets and food avoidance during and after pregnancy.

References

  1. Barennes, H., et al., Beriberi (thiamine deficiency) and high infant mortality in northern Laos. PLoS Negl Trop Dis, 2015. 9(3).