Two-thirds of pregnant women attending antenatal care clinic at the University of Gondar Hospital are found with subclinical iodine deficiency, 2017

Improving Pregnant Women's Iodine Intake Estimates and Its Prevalence of Inadequacy through the Use of Salt and Seasoning Covariates

(1) Measuring usual iodine intake is a complex task due to the food consumption variability and its natural concentration in food. Therefore, the use of covariates to adjust statistical methods to estimate usual intake could improve the estimates obtained through dietary surveys. This study aims to evaluate the influence of salt and seasoning usage covariates on the estimates of usual iodine intake and the prevalence of its inadequacy. (2) A cross-sectional study was conducted with Brazilian pregnant women's food consumption data obtained with 24-h recall (n = 2247). The usual iodine intake was adjusted for intraindividual variability, supplement use, temporal effects, data collection methods, and sociodemographic characteristics with the tool UCD/NCI SIMPLE in the SAS software. Then, salt and seasoning usage covariates were used to adjust the distribution. The harmonized intake reference values for populations were used to assess intake adequacy. (3) The adjustments for salt and seasoning usage yielded a higher mean of usual iodine intakes. The only exception was the adjustment for the "habit of adding salt to meals after preparing/cooking", which produced a lower mean of usual intake and increased the prevalence of insufficient intake. (4) Salt and seasoning usage covariates affect the estimates evaluated. However, more studies are necessary to evaluate the influence observed.

The prevalence of insufficient iodine intake in pregnancy in Africa: a systematic review and meta-analysis

BACKGROUND

Fortification of foodstuffs with iodine, mainly through iodization of salt, which commenced in several African countries after 1995 is the main method for mitigating iodine deficiency in Africa. We assessed the degree of iodine nutrition in pregnancy across Africa before and after the implementation of national iodine fortification programs (CRD42018099434).

METHODS

Electronic databases and gray literature were searched for baseline data before implementation of population-based iodine supplementation and for follow-up data up to September 2020. R-metamedian and metamean packages were used to pool country-specific median urinary iodine concentration (UIC) estimates and derived mean UIC from studies with similar features.

RESULTS

Of 54 African countries, 23 had data on iodine nutrition in pregnancy mostly from subnational samples. Data before 1995 showed that severe iodine deficiency was prevalent in pregnancy with a pooled pregnancy median UIC of 28.6 μg/L (95% CI 7.6-49.5). By 2005, five studies revealed a trend towards improvement in iodine nutrition state in pregnancy with a pooled pregnancy median UIC of 174.1 μg/L (95% CI 90.4-257.7). Between 2005 and 2020 increased numbers of national and subnational studies revealed that few African countries had sufficient, while most had mildly inadequate, and some severely inadequate iodine nutrition in pregnancy. The pooled pregnancy median UIC was 145 μg/L (95% CI 126-172).

CONCLUSION

Improvement in iodine nutrition status in pregnancy following the introduction of fortification of foodstuffs with iodine in Africa is sub-optimal, exposing a large proportion of pregnant women to the risk of iodine deficiency and associated disorders.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018099434.

Systematic review and meta-analysis of iodine deficiency and its associated factors among pregnant women in Ethiopia

Background

Iodine deficiency (ID) is a global public health problem and its impact is more pronounced in low-income countries. During pregnancy, iodine requirement is known to elevate sharply, making pregnant women, especially those living in low-income countries highly vulnerable to iodine deficiency. This study aims to assess the prevalence of iodine deficiency and its associated factors among pregnant women in Ethiopia.

Methods

A systematic literature search was performed by using PubMed, CINAHL, Web of science, global health, and Google scholar electronic databases. Two authors independently extracted all the necessary data using a structured data extraction format. Data analysis was done using STATA Version 14. The heterogeneity of the studies was assessed by using I² test. A random-effects model was used to estimate the pooled prevalence and pooled odds ratio. The presence of publication bias was checked using Funnel plot and Egger’s test.

Results

One thousand one hundred and sixteen studies were reviewed and seven studies fulfilling the inclusion criteria were included in the meta-analysis. The meta-analysis of seven studies that included 2190 pregnant women showed a pooled prevalence of iodine deficiency during pregnancy to be 68.76% (95% CI: 55.21–82.31). In a subgroup analysis, the prevalence in Oromia region is 71.93% (95% CI: 54.87–88.99) and in Amhara region is 60.93% (95% CI: 57.39–64.48). Iodized salt use (AOR = 0.18; 95% CI: 0.08–0.44) and 1st trimester pregnancy (AOR = 0.68; 95% CI: 0.47–0.99) were found to have a significant association with iodine deficiency.

Conclusions

The prevalence of iodine deficiency during pregnancy using urine iodine is considerably high in Ethiopia. Using iodized salt is found to reduce the burden. Hence, there is a need to strengthen iodization programs to tackle the problem.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03584-0.