TY - JOUR
T1 - Spina bifida before and after folic acid fortification in Canada
AU - De Wals, Philippe
AU - Tairou, Fassiatou
AU - Van Allen, Margot I.
AU - Lowry, R. Brian
AU - Evans, Jane A.
AU - Van Den Hof, Michiel C.
AU - Crowley, Marian
AU - Uh, Soo Hong
AU - Zimmer, Pamela
AU - Sibbald, Barbara
AU - Fernandez, Bridget
AU - Lee, Nora S.
AU - Niyonsenga, Theophile
PY - 2008/1/1
Y1 - 2008/1/1
N2 - BACKGROUND: In 1998, fortification of a large variety of cereal products with folic acid became mandatory in Canada. A multicentric study was carried out to assess the impact of this policy on the frequency of NTDs. The present analysis focused on spina bifida. METHODS: The study population included approximately 2 million livebirths, stillbirths, and terminations of pregnancies because of fetal anomalies among women residing in seven Canadian provinces, from 1993 to 2002. Spina bifida cases were divided according to the upper limit of the defect: upper (cranial, cervical, or thoracic) and lower (lumbar or sacral) defects. Based on published results of red blood cell folate tests, the study period was divided into prefortification, partial fortification, and full fortification periods. RESULTS: A total of 1,286 spina bifida cases were identified: 51% livebirths, 3% stillbirths, and 46% terminations. Prevalence decreased from 0.86/1,000 in the prefortification to 0.40 in the full fortification period, while the proportion of upper defects decreased from 32% to 13%. Following fortification, regional variations in the prevalence and distribution of sites almost disappeared. CONCLUSIONS: Results confirmed the etiologic heterogeneity of spina bifida and the more pronounced effect of folic acid in decreasing the risk of the more severe clinical presentations.
AB - BACKGROUND: In 1998, fortification of a large variety of cereal products with folic acid became mandatory in Canada. A multicentric study was carried out to assess the impact of this policy on the frequency of NTDs. The present analysis focused on spina bifida. METHODS: The study population included approximately 2 million livebirths, stillbirths, and terminations of pregnancies because of fetal anomalies among women residing in seven Canadian provinces, from 1993 to 2002. Spina bifida cases were divided according to the upper limit of the defect: upper (cranial, cervical, or thoracic) and lower (lumbar or sacral) defects. Based on published results of red blood cell folate tests, the study period was divided into prefortification, partial fortification, and full fortification periods. RESULTS: A total of 1,286 spina bifida cases were identified: 51% livebirths, 3% stillbirths, and 46% terminations. Prevalence decreased from 0.86/1,000 in the prefortification to 0.40 in the full fortification period, while the proportion of upper defects decreased from 32% to 13%. Following fortification, regional variations in the prevalence and distribution of sites almost disappeared. CONCLUSIONS: Results confirmed the etiologic heterogeneity of spina bifida and the more pronounced effect of folic acid in decreasing the risk of the more severe clinical presentations.
KW - Folic acid
KW - Food
KW - Fortification
KW - Neural tube defect
KW - Program evaluation
KW - Spina bifida
UR - http://www.scopus.com/inward/record.url?scp=52249123448&partnerID=8YFLogxK
U2 - 10.1002/bdra.20485
DO - 10.1002/bdra.20485
M3 - Article
C2 - 18655127
AN - SCOPUS:52249123448
SN - 1542-0752
VL - 82
SP - 622
EP - 626
JO - Birth Defects Research Part A - Clinical and Molecular Teratology
JF - Birth Defects Research Part A - Clinical and Molecular Teratology
IS - 9
ER -