TY - JOUR
T1 - Cigarette smoking and iodine as hypothyroxinemic stressors in U.S. women of childbearing age
T2 - A NHANES III analysis
AU - Vanderver, G. Bruce
AU - Engel, Arnold
AU - Lamm, Steven
PY - 2007/8
Y1 - 2007/8
N2 - Background: Exposure to environmental thiocyanate through smoking has been suggested to lead to hypothyroxinemia, which potentially impairs brain development in the fetuses of affected women, though studies are conflicting. It was hypothesized that iodine status might modulate the effects of thiocyanate exposure on the prevalence of hypothyroxinemia in women of childbearing age. Design: The study population comprised 6967 women (age range: 15-44 years) from the National Health and Nutrition Examination Survey (NHANES) III database. Smoking status was stratified into nonsmokers and those who smoked 1-10, 11-20, 21-30, and 31+ cigarettes a day. Iodine status was stratified based on urinary iodine excretion as 2(4) = 14.15, p = 0.007]. When analyzed by urinary iodine level, the hypothyroxinemic effect of smoking was limited to the highest two urinary iodine strata [χ2(4) = 41.48, p <0.001; and χ2 (4) = 40.62, p <0.001]. A significant interaction effect between smoking and urinary iodine was noted, underscoring the relationship between high levels of urinary iodine excretion and smoking with respect to hypothyroxinemia. Conclusions: Heavy smoking was associated with a higher prevalence of hypothyroxinemia. The impact of thiocyanate exposure from smoking on the prevalence of hypothyroxinemia is limited to those women of childbearing age with the highest urinary iodine excretion. Iodine supplementation should be cautiously considered in women of childbearing age who are smokers.
AB - Background: Exposure to environmental thiocyanate through smoking has been suggested to lead to hypothyroxinemia, which potentially impairs brain development in the fetuses of affected women, though studies are conflicting. It was hypothesized that iodine status might modulate the effects of thiocyanate exposure on the prevalence of hypothyroxinemia in women of childbearing age. Design: The study population comprised 6967 women (age range: 15-44 years) from the National Health and Nutrition Examination Survey (NHANES) III database. Smoking status was stratified into nonsmokers and those who smoked 1-10, 11-20, 21-30, and 31+ cigarettes a day. Iodine status was stratified based on urinary iodine excretion as 2(4) = 14.15, p = 0.007]. When analyzed by urinary iodine level, the hypothyroxinemic effect of smoking was limited to the highest two urinary iodine strata [χ2(4) = 41.48, p <0.001; and χ2 (4) = 40.62, p <0.001]. A significant interaction effect between smoking and urinary iodine was noted, underscoring the relationship between high levels of urinary iodine excretion and smoking with respect to hypothyroxinemia. Conclusions: Heavy smoking was associated with a higher prevalence of hypothyroxinemia. The impact of thiocyanate exposure from smoking on the prevalence of hypothyroxinemia is limited to those women of childbearing age with the highest urinary iodine excretion. Iodine supplementation should be cautiously considered in women of childbearing age who are smokers.
UR - http://www.scopus.com/inward/record.url?scp=36649022285&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=36649022285&partnerID=8YFLogxK
U2 - 10.1089/thy.2006.0332
DO - 10.1089/thy.2006.0332
M3 - Article
C2 - 17725431
AN - SCOPUS:36649022285
SN - 1050-7256
VL - 17
SP - 741
EP - 746
JO - Thyroid
JF - Thyroid
IS - 8
ER -