title: Thyroid Function among Breastfed Children with Chronically Excessive Iodine Intakes.
abstract: Iodine excess may impair thyroid function and trigger adverse health consequences for children. This study aims to describe iodine status among breastfed infants with high iodine exposure in the Saharawi refugee camps Algeria, and further assess thyroid function and iodine status among the children three years later. In 2010, a cross-sectional study among 111 breastfed children aged 0-6 months was performed (baseline study). In 2013, a second cross-sectional study (follow-up study) was conducted among 289 children; 213 newly selected and 76 children retrieved from baseline. Urinary iodine concentration (UIC) and breast milk iodine concentration (BMIC) were measured at baseline. UIC, thyroid hormones and serum thyroglobulin (Tg) were measured at follow-up. At baseline and follow-up, 88% and 72% had excessive iodine intakes (UIC ≥ 300 µg/L), respectively. At follow-up, 24% had a thyroid hormone disturbance and/or elevated serum Tg, including 9% with subclinical hypothyroidism (SCH), 4% with elevated fT3 and 14% with elevated Tg. Children with SCH had poorer linear growth and were more likely to be underweight than the children without SCH. Excessive iodine intakes and thyroid disturbances were common among children below four years of age in our study. Further, SCH seemed to be associated with poor growth and weight.
authors.affiliation: Department of Nursing and Health Promotion, Faculty of Health Sciences, Oslo and Akershus University College, 0130 Oslo, Norway. inger.aakre@hioa.no.|Department of Global Public Health and Primary Care, Faculty of Medicine and Dentistry, University of Bergen, 5018 Bergen, Norway. inger.aakre@hioa.no.
authors.forename: Inger
authors.initials: I
authors.lastname: Aakre
authors.affiliation: Department of Global Public Health and Primary Care, Faculty of Medicine and Dentistry, University of Bergen, 5018 Bergen, Norway. tors@me.com.|Research Department, Innlandet Hospital Trust, 2609 Lillehammer, Norway. tors@me.com.
authors.forename: Tor A
authors.initials: TA
authors.lastname: Strand
authors.affiliation: Department of Medical Biochemistry, Oslo University Hospital, 0379 Oslo, Norway. trine.bjoro@medisin.uio.no.|Institute of Clinical Medicine, University of Oslo, 0379 Oslo, Norway. trine.bjoro@medisin.uio.no.
authors.forename: Trine
authors.initials: T
authors.lastname: Bjøro
authors.affiliation: Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital, 0424 Oslo, Norway. UXINRH@ous-hf.no.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Norheim
authors.affiliation: Department of Nursing and Health Promotion, Faculty of Health Sciences, Oslo and Akershus University College, 0130 Oslo, Norway. ingrid.barikmo@outlook.com.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Barikmo
authors.affiliation: Neonatology Unit, University Hospital La Paz, University of Madrid, 28046 Madrid, Spain. susana.ares@salud.madrid.org.
authors.forename: Susana
authors.initials: S
authors.lastname: Ares
authors.affiliation: Neonatology Unit, University Hospital La Paz, University of Madrid, 28046 Madrid, Spain. marta.duqueal@salud.madrid.org.
authors.forename: Marta Duque
authors.initials: MD
authors.lastname: Alcorta
authors.affiliation: Department of Nursing and Health Promotion, Faculty of Health Sciences, Oslo and Akershus University College, 0130 Oslo, Norway. sigrun.henjum@hioa.no.
authors.forename: Sigrun
authors.initials: S
authors.lastname: Henjum
mesh_terms: D000462:Algeria; D001942:Breast Feeding; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007037:Hypothyroidism / Q000097:blood; D007223:Infant; D007455:Iodine / Q000009:adverse effects* / Q000652:urine; D016014:Linear Models; D008297:Male; D008895:Milk, Human / Q000737:chemistry*; D009752:Nutritional Status; D013954:Thyroglobulin / Q000097:blood; D013961:Thyroid Gland / Q000187:drug effects* / Q000503:physiopathology; D013963:Thyroid Hormones / Q000097:blood
chemical_list: D013963:Thyroid Hormones; D013954:Thyroglobulin; D007455:Iodine
keywords: breast milk iodine; hypothyroidism; iodine excess; iodine intake; thyroglobulin; thyroid function tests; urinary iodine concentration