[Serum folate levels in adolescent population in Madrid, Spain].
OBJECTIVE
Serum folate concentrations in children are essential to establish values which allow to compare different regions or countries, and raise the possibility of fortifying diet with group B vitamins and folic acid as a secondary prevention against cardiovascular diseases.


METHODS
A cross-sectional epidemiological study was performed to assess serum folate levels in school children, aged 13-15 years, in Madrid. Folate and vitamin B12 determinations were determined in blood samples of fasting children. Genotype C677T of methylentetrahydrofolate reductase (MTHFR) enzyme was determined by polymerase chain reaction.


RESULTS
Average folate levels obtained in our study were 7.83 nmol/l (95% confidence interval, 7.42 to 8.23 nmol/l). Median was 6.89 nmol/l (interquartilic range: 5.30 to -9.30 nmol/l). No statistically significant differences were found by gender, age or presence of menstruation. Serum folate concentration decreased significantly with the mutation of the C677T genotype for MTHFR. Prevalence of deficits of folate (< 5.3 nmol/l) was 23.8% and raised significantly with the mutation of the C677T genotype for MTHFR: 18.8% for CC, 20.4% for CT, and 46.7% for TT. This effect was mainly observed in girls after menstruation.


CONCLUSIONS
Homozygosis mutation in C677T genotype of the enzyme MTHFR induces lower folate levels, mainly in girls after menstruation. 5.3 nmol/l is proposed as a threshold to define deficient serum folate levels in the Spanish adolescent population.
Gil
Ruth
R
Area de Medicina Preventiva y Salud Pública, Departamento de Ciencias de la Salud, Universidad Rey Juan Carlos, Laboratorio de Lípidos, Fundación Jiménez Díaz, Madrid, España. ruth.gil@urjc.es
Esteban
Jesús
J
Hernández
Valentín
V
Cano
Beatriz
B
de Oya
Manuel
M
Gil
Angel
A
D000293:Adolescent; D003430:Cross-Sectional Studies; D005260:Female; D005492:Folic Acid / Q000097:blood*; D005838:Genotype; D006801:Humans; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics; D009154:Mutation; D013030:Spain
D005492:Folic Acid; D042965:Methylenetetrahydrofolate Reductase (NADPH2)