title: Iodine status and thyroid function among Spanish schoolchildren aged 6-7 years: the Tirokid study.
abstract: I deficiency is still a worldwide public health problem, with children being especially vulnerable. No nationwide study had been conducted to assess the I status of Spanish children, and thus an observational, multicentre and cross-sectional study was conducted in Spain to assess the I status and thyroid function in schoolchildren aged 6-7 years. The median urinary I (UI) and thyroid-stimulating hormone (TSH) levels in whole blood were used to assess the I status and thyroid function, respectively. A FFQ was used to determine the consumption of I-rich foods. A total of 1981 schoolchildren (52 % male) were included. The median UI was 173 μg/l, and 17·9 % of children showed UI<100 μg/l. The median UI was higher in males (180·8 v. 153·6 μg/l; P<0·001). Iodised salt (IS) intake at home was 69·8 %. IS consumption and intakes of ≥2 glasses of milk or 1 cup of yogurt/d were associated with significantly higher median UI. Median TSH was 0·90 mU/l and was higher in females (0·98 v. 0·83; P<0·001). In total, 0·5 % of children had known hypothyroidism (derived from the questionnaire) and 7·6 % had TSH levels above reference values. Median TSH was higher in schoolchildren with family history of hypothyroidism. I intake was adequate in Spanish schoolchildren. However, no correlation was found between TSH and median UI in any geographical area. The prevalence of TSH above reference values was high and its association with thyroid autoimmunity should be determined. Further assessment of thyroid autoimmunity in Spanish schoolchildren is desirable.
authors.affiliation: 1Endocrinology and Nutrition Department,Hospital de Sant Joan Despí Moisès Broggi,Jacint Verdaguer 90,08970 Sant Joan Despí (Barcelona),Spain.
authors.forename: L
authors.initials: L
authors.lastname: Vila
authors.affiliation: 2Endocrinology and Nutrition Department,Fundación Hospital Alcorcón,Calle Budapest 1, 28922 Alcorcón, Madrid,Spain.
authors.forename: S
authors.initials: S
authors.lastname: Donnay
authors.affiliation: 3Pediatrics Department,Hospital Universitario Donostia,Doctor Begiristain Kalea, 117,20080 Donostia,Gipuzkoa,Spain.
authors.forename: J
authors.initials: J
authors.lastname: Arena
authors.affiliation: 4Endocrinology and Nutrition Department,Hospital Universitario Araba Unibertsitate Ospitalea,Calle Francisco Leandro de Viana 1 Kalea,01009 Vitoria-Gasteiz,Araba,Spain.
authors.forename: J J
authors.initials: JJ
authors.lastname: Arrizabalaga
authors.affiliation: 5Endocrinology and Nutrition Department,Hospital García Orcoyen,C/Santa Soria,22-31200 Estella,Spain.
authors.forename: J
authors.initials: J
authors.lastname: Pineda
authors.affiliation: 6Digestive Diseases Unit,Hospital Carlos Haya,Avenida Carlos Haya,s/n, 29010 Málaga,Spain.
authors.forename: E
authors.initials: E
authors.lastname: Garcia-Fuentes
authors.affiliation: 7Medical Department,Merck S.L.,Calle de María de Molina, 40,28006 Madrid,Spain.
authors.forename: C
authors.initials: C
authors.lastname: García-Rey
authors.affiliation: 8Newborn Screening Laboratory,Biochemical and Molecular Genetics Department,Hospital Clínic,Villarroel, 170, 08036 Barcelona,Spain.
authors.forename: J L
authors.initials: JL
authors.lastname: Marín
authors.affiliation: 9Research Unit, Hospital de Mataró,Consorci Sanitari del Maresme,Carrer Prolongació Cirera, s/n, 08304 Mataró,Barcelona,Spain.
authors.forename: M
authors.initials: M
authors.lastname: Serra-Prat
authors.affiliation: 10Pediatrics, Obstetrics & Gynecology Unit,Hospital Riotinto,Avenida Esquila, 5,21660 Minas de Riotinto,Huelva,Spain.
authors.forename: I
authors.initials: I
authors.lastname: Velasco
authors.affiliation: 11Endocrinology and Nutrition Department,Complejo Asistencial de Ávila,Av. Juan Carlos I, s/n, 05071 Ávila,Spain.
authors.forename: A
authors.initials: A
authors.lastname: López-Guzmán
authors.affiliation: 12Endocrinology and Nutrition Department,Hospital Universitario Infanta Cristina,Av. Elvas, s/n, 06006 Badajoz,Spain.
authors.forename: L M
authors.initials: LM
authors.lastname: Luengo
authors.affiliation: 13Endocrinology and Nutrition Department,Hospital Clínico de Valladolid,Calle Ramón y Cajal, s/n, 47005 Valladolid,Spain.
authors.forename: A
authors.initials: A
authors.lastname: Villar
authors.affiliation: 14Area Básica de Salud (ABS) Ariza,C/De La Paz Ariza,50220 Zaragoza,Spain.
authors.forename: Z
authors.initials: Z
authors.lastname: Muñoz
authors.affiliation: 15Endocrinology and Nutrition Department,Hospital Royo Villanova,Avda. San Gregorio, s/n, 50015 Zaragoza,Spain.
authors.forename: O
authors.initials: O
authors.lastname: Bandrés
authors.affiliation: 16Endocrinology and Nutrition Department,Hospital Río Carrión,Av. Donantes de Sangre, s/n, 34005 Palencia,Spain.
authors.forename: E
authors.initials: E
authors.lastname: Guerrero
authors.affiliation: 17Área Básica de Salud (ABS) de la Seu d'Urgell,Pg. Joan Brudieu,8, 25700 La Seu d'Urgell,Lleida,Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Muñoz
authors.affiliation: 18Endocrinology and Nutrition Department,Hospital de Inca,Carretera Vella de Llubí,S/N,07300 Inca,Islas Baleares,Spain.
authors.forename: G
authors.initials: G
authors.lastname: Moll
authors.affiliation: 18Endocrinology and Nutrition Department,Hospital de Inca,Carretera Vella de Llubí,S/N,07300 Inca,Islas Baleares,Spain.
authors.forename: F
authors.initials: F
authors.lastname: Vich
authors.affiliation: 19Endocrinology and Nutrition Department,Hospital Central de Asturias,Avenida de Roma, s/n, 33011 Oviedo,Asturias,Spain.
authors.forename: E
authors.initials: E
authors.lastname: Menéndez
authors.affiliation: 20Endocrinology and Nutrition Department,Hospital de Cabueñes,Camino de los Prados 395,33394 Gijón,Spain.
authors.forename: M
authors.initials: M
authors.lastname: Riestra
authors.affiliation: 1Endocrinology and Nutrition Department,Hospital de Sant Joan Despí Moisès Broggi,Jacint Verdaguer 90,08970 Sant Joan Despí (Barcelona),Spain.
authors.forename: Y
authors.initials: Y
authors.lastname: Torres
authors.affiliation: 12Endocrinology and Nutrition Department,Hospital Universitario Infanta Cristina,Av. Elvas, s/n, 06006 Badajoz,Spain.
authors.forename: P
authors.initials: P
authors.lastname: Beato-Víbora
authors.affiliation: 21Endocrinology and Nutrition Department,Hospital General de Ciudad Real,Calle del Obispo Rafael Torija,s/n, 13005 Ciudad Real,Spain.
authors.forename: M
authors.initials: M
authors.lastname: Aguirre
authors.affiliation: 22Endocrinology and Nutrition Department,Complejo Hospitalario de Jaén,Av. del Ejército Español,10, 23007 Jaén,Spain.
authors.forename: P
authors.initials: P
authors.lastname: Santiago
authors.affiliation: 23Endocrinology and Nutrition Department,Hospital Virgen de la Luz de Cuenca,Hermandad Donantes de Sangre,s/n, 16002 Cuenca,Spain.
authors.forename: J
authors.initials: J
authors.lastname: Aranda
authors.affiliation: 24Endocrinology and Nutrition Department,Institute of Biomedical Research of Málaga (IBIMA),Hospital Regional Universitario de Málaga,Plaza del Hospital Civil s/n, 29009 Málaga,Spain.
authors.forename: C
authors.initials: C
authors.lastname: Gutiérrez-Repiso
mesh_terms: D003430:Cross-Sectional Studies; D003611:Dairy Products; D003677:Deficiency Diseases / Q000453:epidemiology* / Q000652:urine; D004032:Diet; D004034:Diet Surveys; D005190:Family; D005260:Female; D050031:Hashimoto Disease / Q000097:blood / Q000453:epidemiology*; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000453:epidemiology*; D007455:Iodine / Q000008:administration & dosage / Q000172:deficiency* / Q000652:urine; D008297:Male; D009752:Nutritional Status; D015995:Prevalence; D012737:Sex Factors; D017673:Sodium Chloride, Dietary / Q000008:administration & dosage; D013030:Spain / Q000453:epidemiology; D013961:Thyroid Gland; D013972:Thyrotropin / Q000097:blood*
chemical_list: D017673:Sodium Chloride, Dietary; C034024:iodized salt; D013972:Thyrotropin; D007455:Iodine
keywords: AC autonomous communities; ID iodine deficiency; IS iodised salt; Iodine deficiency; Iodine status; P25 and P75 25th and 75th percentiles; RV reference values; TSH thyroid-stimulating hormone; Thyroid function; UI urinary iodine; UIC urinary iodine concentration; Urinary iodine