Since 1990, the mortality rate for children born with Down syndrome and a congenital heart defect has more than halved. This has been shown by a study by the University of Gothenburg. However, the mortality rate in this group is still 85% higher, compared to others who have a congenital heart defect but were not born with Down syndrome.
The research leader behind the study is Zacharias Mandalenakis, who is an Associate Professor at the Sahlgrenska Academy at the University of Gothenburg, and Senior Consultant in Cardiology at Sahlgrenska University Hospital.
The study has been published in the Journal of the American Heart Association and is based on registry data from the whole of Sweden for people with Down syndrome and congenital heart defects born between 1970 and 2017. A total of 3,285 patients with Down syndrome and congenital heart defects, and 64,529 patients with heart defects but without Down syndrome, were included. Each of those with Down syndrome was also compared with eight matched controls – i.e., people from the general population of the same age and gender, but without Down syndrome or congenital heart disease.
The study shows that people with Down syndrome and heart defects have a much better survival rate, although the mortality rate for this group remains increased. Children born before 1990 with Down syndrome and heart defects had a mortality rate that was about 47 times higher than children born without either Down syndrome or a heart defect. For children born since 1990, the mortality rate has more than halved. This is now 18 times higher for people born with Down syndrome and heart defects, compared to the normal population.
For the entire period 1970-2017, people with Down syndrome and congenital heart disease had a 25-fold greater mortality compared to the control group (who had neither Down syndrome nor heart disease). Compared to other people with heart defects, the mortality rate in the Down syndrome group was doubled throughout the period. In the latter part of the period, after the turning point in 1990, the mortality rate among those with Down syndrome was 85% higher, compared to others with a congenital heart defect.
