| The objective of this retrospective, population-based cross-sectional cohort study was to assess whether folic acid food fortification was associated with a decline in the incidence of neuroblastoma in Ontario. We investigated the incidence of neuroblastoma, registered by the Pediatric Oncology Group of Ontario, before and after the introduction of folic acid fortification. The study cohort included 324 neuroblastoma cases of 2 242 438 total Ontario births during the study period (January 1985 to December 2000). An interventional time series analysis demonstrated that the incidence of neuroblastoma declined from 1.57 to 0.62 per 10 000 births after folic acid fortification (P < 0.0001). The crude IRR (0.40, 95% CI 0.25–0.64) remained significant after adjusting for both age and disease stage at diagnosis (adjusted IRR 0.38, 95% CI 0.23–0.62). The results of this study suggest that folic acid food fortification is associated with a significant decline in the incidence of neuroblastoma. |
