Background and Aims Born in Bradford is a birth cohort study established in March 2007 to look at health and outcomes in a multi ethnic population in Bradford (UK). We aimed to establish whether South Asian children in the cohort had a higher prevalence of congenital cardiac anomalies compared to non South Asians, and evaluate association with consanguinity.
Methods Babies with cardiac anomalies in the cohort born between May 2007 and March 2010 identified using multiple ascertainment models. Ethnicity ascribed to cases using clinical records & inferred to cohort based on questionnaire responses. Data on consanguinity and other cofounders were obtained from database. Statistical analysis done by Chi square test and logistic regression.
Results Structural congenital cardiac defects=96 cases. Overall prevalence rate=8.8/1000 live births. Prevalence was significantly higher in South Asians compared to non South Asians for all cardiac anomalies (11/1000 vs 6.2/1000, P<0.05) & anomalies including only VSDs requiring surgery (8.7/1000 vs 4.4/1000, P<0.05) implying that the differences were unlikely due to ascertainment bias. Complex cardiac defects were more prevalent in South Asians, cyanotic defects were significantly higher in this group P=0.017. South Asian ethnicity (Odds-ratio=1.76, P=0.019) and consanguinity (Odds-ratio=2.002, P=0.003) significantly increased the risk for cardiac anomalies in univariate analysis. Multivariate analysis incorporating confounding factors attenuated their effect; however consanguinity remained a borderline significant predictor.
Conclusions We have demonstrated an apparent excess of congenital cardiac anomalies in South Asians in the Born in Bradford cohort. Consanguinity seemed to increase the risk for cardiac anomalies.