Objective: To determine whether Aboriginal Canadians from Manitoba and Ontario have an increased incidence of isolated total anomalous pulmonary venous drainage (TAPVD) and to compare results obtained from two different data sources and time periods.
Design: A nonconcurrent cohort study was undertaken. Incidence rates and relative risk from 'traditional' data sources (cases from medical records data; births from Census, Vital Statistics and Native Registry data for Manitoba and Ontario) from 1972-84 were derived and compared with those from computerized hospital abstract data from Manitoba for 1987-91.
Results: Using traditional data sources an incidence of 0.282/1000 live births was noted in Aboriginals versus 0.062 in non-Aboriginals for a relative risk of 4.6 (95% CI = 2.7-7.7). For Manitoba only the relative risk was 5.8 (95% CI = 2.6-12.8). Using computerized administrative data from Manitoba the relative risk was 5.8 (95% CI = 1.3-25.8).
Conclusion: There is an increased incidence of isolated TAPVD in Aboriginal peoples from Manitoba and Ontario. Further epidemiological investigation is necessary to determine the nature of this association.