Evaluation of iron status in European adolescents through biochemical iron indicators: the HELENA Study.
OBJECTIVE
To assess the iron status among European adolescents through selected biochemical parameters in a cross-sectional study performed in 10 European cities.


METHODS
Iron status was defined utilising biochemical indicators. Iron depletion was defined as low serum ferritin (SF<15 μg/l). Iron deficiency (ID) was defined as high-soluble transferrin receptor (sTfR>8.5 mg/l) plus iron depletion. Iron deficiency anaemia (IDA) was defined as ID with haemoglobin (Hb) below the WHO cutoff for age and sex: 12.0 g/dl for girls and for boys aged 12.5-14.99 years and 13.0 g/dl for boys aged ≥15 years. Enzyme linked immunosorbent assay was used as analytical method for SF, sTfR and C-reactive protein (CRP). Subjects with indication of inflammation (CRP >5 mg/l) were excluded from the analyses. A total of 940 adolescents aged 12.5-17.49 years (438 boys and 502 girls) were involved.


RESULTS
The percentage of iron depletion was 17.6%, significantly higher in girls (21.0%) compared with boys (13.8%). The overall percentage of ID and IDA was 4.7 and 1.3%, respectively, with no significant differences between boys and girls. A correlation was observed between log (SF) and Hb (r = 0.36, P < 0.01), and between log (sTfR) and mean corpuscular haemoglobin (r = -0.30, P < 0.01). Iron body stores were estimated on the basis of log (sTfR/SF). A higher percentage of negative values of body iron was recorded in girls (16.5%) with respect to boys (8.3%), and body iron values tended to increase with age in boys, whereas the values remained stable in girls.


CONCLUSIONS
To ensure adequate iron stores, specific attention should be given to girls at European level to ensure that their dietary intake of iron is adequate.
National Research Institute on Food and Nutrition, Rome, Italy. ferrari@inran.it
M
M
Ferrari
L
L
Mistura
E
E
Patterson
M
M
Sjöström
L E
LE
Díaz
P
P
Stehle
M
M
Gonzalez-Gross
M
M
Kersting
K
K
Widhalm
D
D
Molnár
F
F
Gottrand
S
S
De Henauw
Y
Y
Manios
A
A
Kafatos
L A
LA
Moreno
C
C
Leclercq
D000293:Adolescent; D017195:Adolescent Nutritional Physiological Phenomena / Q000502:physiology; D018798:Anemia, Iron-Deficiency / Q000097:blood / Q000453:epidemiology*; D015415:Biomarkers / Q000097:blood; D001774:Blood Chemical Analysis; D003430:Cross-Sectional Studies; D005060:Europe / Q000453:epidemiology; D005260:Female; D005293:Ferritins / Q000097:blood; D006801:Humans; D007501:Iron / Q000097:blood*; D000090463:Iron Deficiencies; D008297:Male; D009752:Nutritional Status; D015995:Prevalence; D012737:Sex Factors
D015415:Biomarkers; D005293:Ferritins; D007501:Iron
Bull World Health Organ. 1995;73(3):375-86
7614670
Blood. 2003 May 1;101(9):3359-64
12521995
Nutr Health. 1987;4(4):195-203
3554043
Proc Nutr Soc. 1999 May;58(2):489-95
10466194
J Adolesc Health. 2005 Jul;37(1):75
15963912
Clin Chim Acta. 2008 Apr;390(1-2):90-6
18237548
Public Health Nutr. 2006 Feb;9(1):26-34
16480530
Am J Clin Nutr. 2009 May;89(5):1334-42
19357218
Annu Rev Med. 1993;44:63-74
8476268
Annu Rev Nutr. 1986;6:13-40
3524613
Int J Obes (Lond). 2008 Nov;32 Suppl 5:S12-8
19011647
Am J Clin Nutr. 2010 Jun;91(6):1784-90
20410090
Acta Paediatr. 1996 Sep;85(9):1033-8
8888913
Am J Clin Nutr. 1998 Oct;68(4):880-7
9771866
Br J Haematol. 1993 Dec;85(4):787-98
7918045
JAMA. 2002 Nov 6;288(17):2114-6
12425310
Br J Sports Med. 2011 Jan;45(1):20-9
19700434
Annu Rev Nutr. 2003;23:41-58
12704220
Blood. 1990 May 1;75(9):1870-6
2331526
Public Health Nutr. 2001 Apr;4(2B):537-45
11683548
Br J Nutr. 2008 Jun;99 Suppl 3:S2-9
18598585
Acta Haematol. 2003;110(4):213-6
14663171
J Pediatr Hematol Oncol. 2006 May;28(5):316-21
16772884
Eur J Haematol. 2005 Oct;75(4):309-17
16146537
J Nutr. 2004 Nov;134(11):3127-32
15514286
J Lab Clin Med. 1992 Apr;119(4):385-90
1583389
Int J Obes (Lond). 2008 Nov;32 Suppl 5:S66-75
19011656
BMJ. 1989 Feb 25;298(6672):499
2495083
Hematology. 2007 Jun;12(3):249-53
17558702
Nutr J. 2010 Jan 25;9:4
20100340
Can J Cardiovasc Nurs. 2009;19(1):26-32
19226888
Pediatrics. 2001 Jun;107(6):1381-6
11389261
Int J Obes (Lond). 2008 Nov;32 Suppl 5:S4-11
19011652