title: Increased serum soluble transferrin receptor concentration detects subclinical iron deficiency in healthy adolescent girls.
abstract: The objective of this study was to investigate whether the measurement of serum soluble transferrin receptor could detect subclinical iron deficiency in adolescent girls, and to assess the possible specificity-compromising effects of growth, menarche, and intensive physical activity. The study population consisted of 191 physically active (control) girls aged 9-15 years. Dietary iron intake was estimated at baseline, and after 6 and 12 months. Iron status of the subjects was assessed by haematological laboratory tests at 6 and 12 months. A 3-month iron and multivitamin supplementation was started after the visit at 6 months. The supplementation consistently decreased soluble transferrin receptor concentrations in subjects with initial values greater than 2.4 mg/l, which was determined by regression analysis to be the cut-off value for iron-deficient erythropoiesis. The 95% reference interval in the iron-replete subjects (0.9-2.4 mg/l) was consistent with this finding. In our population, the incidence of subclinical iron deficiency was 10%. Growth or physical activity had no effect on the iron status. This study shows that, similarly to adults, soluble transferrin receptor measurement can be used to detect subclinical iron deficiency in adolescents (competitive athletes or normal controls). We suggest that soluble transferrin receptor concentrations above 2.4 mg/l indicate clinically relevant iron deficiency in adolescents.
authors.affiliation: Department of Clinical Chemistry, Turku University Central Hospital, Turku, Finland. timo.takala@tyks.fi
authors.forename: Timo I
authors.initials: TI
authors.lastname: Takala
authors.forename: Pauli
authors.initials: P
authors.lastname: Suominen
authors.forename: Marjo
authors.initials: M
authors.lastname: Lehtonen-Veromaa
authors.forename: Timo
authors.initials: T
authors.lastname: Möttönen
authors.forename: Jorma
authors.initials: J
authors.lastname: Viikari
authors.forename: Allan
authors.initials: A
authors.lastname: Rajamäki
authors.forename: Kerttu
authors.initials: K
authors.lastname: Irjala
mesh_terms: D000293:Adolescent; D000367:Age Factors; D018798:Anemia, Iron-Deficiency / Q000175:diagnosis*; D002648:Child; D004032:Diet; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D000090463:Iron Deficiencies; D015233:Models, Statistical; D011990:Receptors, Transferrin / Q000097:blood*; D012044:Regression Analysis; D013997:Time Factors; D014815:Vitamins / Q000494:pharmacology
chemical_list: D011990:Receptors, Transferrin; D014815:Vitamins