Decline of neural tube defects cases after a folic acid campaign in Nuevo León, México.
BACKGROUND
Nuevo León is a state in northeastern Mexico, near the border of Texas. Mean mortality rate from 1996-98 due to anencephaly cases was 0.6/1,000. In 1999 a surveillance program for the registry and prevention of neural tube defects (NTD) cases was initiated.


METHODS
Cases were obtained from hospitals and OB-GYN clinics by immediate notification, death certificates, or fetal death registries. Only isolated cases of NTD were included. In August 1999 a folic acid campaign was initiated with the free distribution of the vitamin to low-income women with a recommendation to take a 5.0-mg pill once a week. Number of cases and rates from 1999 to 2001 were compared (chi(2) test).


RESULTS
After 2 years there has been a significant reduction in the number of cases and rates. In 1999 there were 95 NTD cases and in the years 2000 and 2001 there were only 59 and 55 respectively (P < 0.001). NTD rate decreased from 1.04/1,000 in 1999 to 0.58/1,000 in 2001. Anencephaly and spina bifida rates decreased from 0.55/1,000 to 0.29/1,000 and from 0.47/1,000 to 0.22/1,000 respectively, from 1999-2001. Decrease of female cases was higher than male cases for both phenotypes.


CONCLUSIONS
After 2 years there was a 50% decrease in the incidence of anencephaly and spina bifida cases with a significant reduction of infant mortality and disability. These results encourage us to propose the use of a single tablet of 5.0-mg of folic acid per week as an alternative to supplementation on a daily basis.
Martínez de Villarreal
Laura
L
Unidad de Genética y Defectos Congénitos, Facultad de Medicina, Universidad Autónoma de Nuevo León, Monterrey, N.L. Mexico. lauramart@ccr.dsi.uanl.mx
Pérez
Jesús Z Villarreal
JZ
Vázquez
Patricia Arredondo
PA
Herrera
Ricardo Hernández
RH
Campos
Ma Del Roble Velazco
Mdel R
López
Roberto Ambriz
RA
Ramírez
José Luis Herrera
JL
Sánchez
Jesús Manuel Yañez
JM
Villarreal
Juan José Morales
JJ
Garza
Manuel Treviño
MT
Limón
Adriana
A
López
Abel Guzmán
AG
Bárcenas
Mario
M
García
Juan Ramón Cepeda
JR
Domínguez
Andrés Sánchez
AS
Nuñez
Rogelio Hernández
RH
Ayala
Jorge Luis García
JL
Martínez
Jorge Garza
JG
González
Mario Tijerina
MT
Alvarez
Carlos García
CG
Castro
Roberto Negrete
RN
D000757:Anencephaly / Q000453:epidemiology / Q000517:prevention & control; D019587:Dietary Supplements; D004677:Encephalocele / Q000453:epidemiology / Q000517:prevention & control; D005260:Female; D005492:Folic Acid / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008800:Mexico / Q000453:epidemiology; D009436:Neural Tube Defects / Q000453:epidemiology* / Q000517:prevention & control; D011159:Population Surveillance; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology; D011295:Prenatal Care; D015995:Prevalence; D012042:Registries; D012424:Rural Population; D012737:Sex Factors; D016135:Spinal Dysraphism / Q000453:epidemiology / Q000517:prevention & control; D014505:Urban Population
D005492:Folic Acid