TEMPORAL TRENDS IN PREVALENCE OF CARDIOVASCULAR MALFORMATIONS IN MARYLAND AND THE DISTRICT-OF-COLUMBIA, 1981-1988

We studied the yearly occurrence of isolated cardiovascular malformati ons in liveborns for the period 1981-1988 in Maryland and the District of Columbia. We used Poisson regression to fit yearly prevalence at b irth as a function of time for all cardiovascular malformation case ty pes combined and for three diagnostic subgroups. We give results separ ately by diagnostic method and race (white/nonwhite), with categories combined when appropriate. Time trends were similar for both races exc ept in pulmonic stenosis diagnosed by echocardiography. The yearly pre valence for all case types, all races, and all diagnostic methods comb ined increased from 28 to 43 per 10,000 livebirths over the 8 years, d ue to an increase in the rate among infants diagnosed by echocardiogra phy. For every diagnostic-type-by-race group studied, there were incre ases in the prevalence for those diagnosed by echocardiography and dec reases (or no change in one group) for those diagnosed by cardiac cath eterization and/or surgery. Although there may have been an increase i n actual occurrence of cardiovascular malformation over our study peri od, it is also possible that wider use of a new echocardiography techn ology resulted in increased detection.