Table 3.
Mean Levels of Maternal Folate-Dependent Biomarkers of One-Carbon Metabolism by Interval between Birth of Index Child and Collection of Maternal Blood Sample for Mothers of Children with Oral Cleftsa and Mothers of Controls
| Maternal biomarker | Maternal group and sample size | Interval between birth of index child and collection of maternal blood sample
|
|||
|---|---|---|---|---|---|
| 12–36 months | >36 to ≤60 months | >60 months | p-valueb | ||
| Plasma folate (nmol/L) | Oral cleft cases (n = 347) | 58.9 (29.4) | 44.9 (22.2) | 47.9 (23.4) | <0.001 |
| Controls (n = 468) | 64.4 (33.2) | 64.5 (33.7) | 65.1 (33.6) | <0.98 | |
| Erythrocyte folate (nmol/L) | Oral cleft cases (n = 345) | 2064 (840) | 1743 (621) | 1905 (803) | <0.01 |
| Controls (n = 465) | 2106 (797) | 2013 (778) | 2210 (881) | <0.13 | |
| Plasma pyridoxal-5′-phosphate (nmol/L) | Oral cleft cases (n = 347) | 65.9 (59.7) | 55.9 (57.9) | 53.6 (55.5) | <0.19 |
| Controls (n = 468) | 60.7 (44.0) | 67.0 (65.0) | 61.0 (55.0) | <0.56 | |
| Plasma total homocysteine (μmol/L) | Oral cleft cases (n = 327) | 4.05 (1.31) | 4.37 (1.37) | 4.56 (1.42) | <0.01 |
| Controls (n = 426) | 4.00 (1.40) | 4.17 (1.29) | 4.26 (1.24) | <0.21 | |
a
Cases include all oral clefts with the exclusion of known genetic syndromes and chromosomal abnormalities.
b
p values for ANOVA test of differences between means of biomarkers between intervals within cases or controls.