Comparison of neonatal thyroid-stimulating hormone levels and indicators of iodine deficiency in school children

Copeland, Daphne; Sullivan, Kevin M.; Houston, Robin; May, W; Mendoza, I. Gómez; Quazi, Salamatullah; Solomons, Noel W.; Nordenberg, Dale; Maberly, Glen

doi:10.1079/phn2001306

Cited by 31 publications

(19 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In 1 study, a high prevalence of elevated TSH concentrations was found at study sites in Bangladesh, Guatemala, and Atlanta, Georgia; values were Ͼ5 mU/L in 84%, 58%, and 82% of neonatal cord blood specimens, respectively, which suggests severe iodine deficiency at all sites. 28 The median UI values among pregnant women at each of the sites were 96, 120, and 105 g/L, respectively, which indicates that the pregnant women at all 3 study sites had insufficient iodine intakes on average. However, the authors suggested that the elevated newborn TSH concentrations in the US samples might have been due, in part, to ␤-iodine antiseptic exposure among 98% of the mothers for intravenous access, bladder catheterization, or epidural anesthesia (see "Iodine Excess") rather than true chronic maternal iodine deficiency.…”

Section: Iodine Deficiencymentioning

confidence: 99%

The Impact of Transient Hypothyroidism on the Increasing Rate of Congenital Hypothyroidism in the United States

et al. 2010

View full text Add to dashboard Cite

The reported incidence rate of primary congenital hypothyroidism (CH) has been increasing in the United States over the past 2 decades. We have considered the possibility that the inclusion of cases of transient hypothyroidism has inflated the reported incidence rate of CH. Assessing the effects of cases of transient hypothyroidism on the incidence rate is problematic, because the definitions, diagnostic criteria, and differentiation from transient hyperthyrotropinemia vary widely among state newborn screening programs. Among the 4 etiologies for transient hypothyroidism (maternal thyrotropin receptor-blocking antibodies, exposure to maternal antithyroid medications, iodine deficiency, and iodine excess), there is little evidence of increases in the incidence rate from thyrotropin receptor-blocking antibodies. Exposure to antithyroid drugs could contribute significantly to the incidence rate of transient CH, given the high estimated incidence of active maternal hyperthyroidism. Iodine deficiency or excess in the United States seems unlikely to have contributed significantly to the incidence rate of CH, because the secular trend toward lower iodine intake among women of reproductive age in the 1980s and 1990s seems to have plateaued, and perinatal iodine exposure has presumably declined as a result of recommendations to discontinue using iodinecontaining disinfectants. Although the female-to-male sex ratio among newborns with thyroid agenesis or dysgenesis (the most common causes of CH) is typically 2:1, analysis of the sex ratio of newborns diagnosed with presumed CH in the United States suggests that a substantial proportion might have transient hypothyroidism or hyperthyrotropinemia, because the sex ratio has been well below the expected 2:1 ratio. Combined ultrasonography and 123 I scintigraphy of the thyroid gland are effective tools for identifying cases of thyroid agenesis and dysgenesis and can help to differentiate cases of transient hypothyroidism from true CH. Imaging is also a vital component in evaluating children who, at 3 years of age, undergo a trial of discontinuation of levothyroxine treatment to test for persistence of hypothyroidism. Ultimately, thyroid gland imaging, in conjunction with longterm follow-up studies that appropriately assess and report whether there was permanence of hypothyroidism, will be necessary to address the true incidence rate of CH and any contribution to the observed rate by transient cases of hypothyroidism or hyperthyrotropinemia.

show abstract

Section: Iodine Deficiencymentioning

confidence: 99%

The Impact of Transient Hypothyroidism on the Increasing Rate of Congenital Hypothyroidism in the United States

et al. 2010

View full text Add to dashboard Cite

show abstract

“…An additional literature search identified seven publications that included two or more of our population groups of interest. Of these, four surveys from three publications met the inclusion criteria for this analysis [11,14,15]. If the survey results were summarized at various geographic levels (e.g., at both the national and provincial levels), we used estimates from the smallest geographic level in the analysis in order to have the most possible data points.…”

Section: Methodsmentioning

confidence: 99%

Comparison of Median Urinary Iodine Concentration as an Indicator of Iodine Status among Pregnant Women, School-Age Children, and Nonpregnant Women

Wong¹,

Sullivan²,

Perrine³

et al. 2011

Food Nutr Bull

View full text Add to dashboard Cite

show abstract

“…and may be affected by factors such as the use of iodinecontaining antiseptics (28,29). No ready explanation is available for the shift to the right in blood TSH distribution in the absence of an increase in blood TSH values >5.0 mIU=L.…”

mentioning

confidence: 98%

Can Neonatal TSH Screening Reflect Trends in Population Iodine Intake?

Burns

Mayne

O’Herlihy

et al. 2008

Thyroid

View full text Add to dashboard Cite

These data support a link between fetal thyroid function and a fall in maternal iodine intake. While the findings of the proportion of blood TSH values >5.0 mIU/L exclude severe maternal or fetal iodine deficiency, a trend toward increasing TSH may provide an early indication of impending iodine deficiency. The findings assume greater importance in the context of declining UI reported from many developed countries even where the proportion of blood TSH values >5.0 mIU/L is <3%, thus excluding severe maternal and fetal iodine deficiency.

show abstract

Comparison of neonatal thyroid-stimulating hormone levels and indicators of iodine deficiency in school children

Cited by 31 publications

References 29 publications

The Impact of Transient Hypothyroidism on the Increasing Rate of Congenital Hypothyroidism in the United States

The Impact of Transient Hypothyroidism on the Increasing Rate of Congenital Hypothyroidism in the United States

Comparison of Median Urinary Iodine Concentration as an Indicator of Iodine Status among Pregnant Women, School-Age Children, and Nonpregnant Women

Can Neonatal TSH Screening Reflect Trends in Population Iodine Intake?

Contact Info

Product

Resources

About