Iodine Deficiency Disorders After Sixteen Years of Universal Dietary Salt Iodization in a Severe Iodine Deficiency Village in Niger

ABSTRACT

Introduction:

Since 1996, Niger has officially adopted the universal dietary salt iodization program (UDSI).

Objective:

It is a before‑after trial study conducted to determine the impact of UDSI program in Tiguey 16 years after.

Subjects and methods:

The study was centered on 371 volunteers whose thyroid gland was palpated and urinary iodine concentration (UIC) determined in 319 of them.

Results:

The total goitre rate (TGR) was 13.20% with 9.70% invisible but palpable goitre (G1) and 3.50% visible goitre (G2). In 1987, the TGR was 77.15%, with 25.25% G1 and 51.90 % G2. The median UIC was 166.00 μg/L, the 20th percentile 66.40 μg/L and the 80^th percentile was 300 μg/L. 68.34 % of the volunteers had a UIC ≥ 100 μg/L, 2.51% <20 μg/L, 10.97% between 20 and 49 μg/L and 18.18% between 50 and 99 μg/L. In 1987, only 3.96% of the studied sample had a UIC ≥ 100 μg/L, 45 % had a UIC <20 μg/L, 35% between 20 and 49 μg/L and 16% from 50 to 99 μg/L. No significant relationship was found between UIC and age and gender or goitre prevalence and gender (P> 0.05). However, goitre prevalence increases significantly with age (p < 0.05).

Conclusion:

The implementation of the UDSI program in Niger decreased goitre prevalence and significantly improved the nutritional iodine status of the populations of Tiguey. However a slight endemic goitre and mild to moderate iodine deficiency persists.

Keywords:

Goitre, iodine deficiency disorders (IDD), salt iodization, thyroid, urinary iodine concentrations (UIC).