Prevalence rates of spina bifida in Alberta, Canada: 2001–2015. Can we achieve more prevention?

Abstract

Background Despite a substantial prevention of neural tube defects with mandatory folic acid (FA) fortification, a significant number of cases still exist in Alberta, Canada, particularly spina bifida (SB). The purpose of this study was to review cases with SB to provide a possible explanation as to why SB is still prevalent in Alberta. Methods Cases with SB born between 2001 and 2015, ascertained by the Alberta Congenital Anomalies Surveillance System, were reviewed. Cases were classified as lipomeningomyelocele, syndrome/recognized condition, chromosome, associated multiple congenital anomalies, and isolated. The notice of birth forms were reviewed to determine FA supplement use before and/or during pregnancy. Socioeconomic status (SES) was also examined. Results The majority of cases were isolated (58%). The total prevalence of SB for 2001–2015 was 0.37/1,000 births, with isolated SB being 0.21/1,000 births. Urinary and congenital heart defects were the most frequently identified associated anomalies. FA supplementation could not be determined for 69% of our cases because of a lack of completeness of the notice of birth forms. There was no significant difference regarding SES between mothers of cases and all mothers in Alberta. Conclusions It is important to examine cases with isolated SB to determine why mandatory FA fortification has not completely prevented SB and to identify which cases are not folate‐responsive. A more concerted effort of public health education and promotion with the identification of women with suboptimal folate status and a better understanding of the role of other micronutrients is necessary.

The Alberta Congenital Anomalies Surveillance System: a 40-year review with prevalence and trends for selected congenital anomalies, 1997–2019

“…2 Folic acid fortification was introduced in Canada in 1998 and has had a significant impact on the prevalence of NTDs. Nevertheless, a substantial number of such defects remain, 6 which may be due to red blood cell folate levels being below 906 nmol/L and/or the need to supplement with vitamin B12 7 or inositol. 8 Additional risk factors include maternal obesity, diabetes mellitus and the use of anticonvulsants and folic acid antagonists.…”

Prevalence rates study of selected isolatednon‐Mendeliancongenital anomalies in the Hutterite population of Alberta, 1980–2016

“…It has been especially successful in Canada (De Wals et al, 2007) and Alberta (Godwin et al, 2008), reducing the prevalence of spina bifida by 50%. Despite this success there remains a residual number of isolated spina bifida cases in Alberta (Lowry et al, 2018) with an isolated spina bifida rate of 0.21/1,000 total births.…”

Spina bifida and pediatric cancers

“…We additionally conducted sensitivity analyses to determine whether the association persisted after exclusion of genetic syndromes associated with spina bifida (using syndromes previously identified 18,19 ). However, there were no cancer cases with spina bifida who had ICD codes in their medical records of these syndromes.…”