Status of Thiamin deficiency in boarding school children from seven districts in Bhutan with previous history of peripheral neuropathy outbreaks: a cohort study.

Introduction: Peripheral neuropathy outbreaks have been a common occurrence amongst boarding schoolchildren from seven districts in Bhutan. Thiamin deficiency has always been suspected to be the cause but the status of the vitamin has never been established. This study aims to find the status of thiamin and dietary intake of micronutrients in boarding schoolchildren from seven districts with previous history of peripheral neuropathy outbreaks. Methods: Whole blood thiamin and dietary intake of micronutrients were assessed in 448 schoolchildren for four study periods (SP). Baseline data (SP1) was collected when the schoolchildren just joined the school at the start of the school academic year. SP2 was the first half of the school year and the data was collected just before the midterm break. SP3 was the short summer break and SP4 the second half of the school academic year. Results: 50.58% of the schoolchildren were found to be thiamin deficient at baseline which increased to 90.1% in SP2. The percentage of thiamin deficient schoolchildren increased to 91.8% in SP3 and then decreased to 79.82% in SP4. The requirements for vitamin B1, B12, vitamin A and iron were never met by dietary intakes in all the study periods. Conclusions: In conclusion, this study found a high prevalence of thiamin deficiency in schoolchildren at baseline and the number of school children with thiamin deficiency increased when in schools. The school children also had inadequate dietary intake of many micronutrients.