Exploring the impact of altitude on congenital heart defects in Saudi Arabia

Abstract

Abstract Congenital heart defects (CHD) have a complex etiology in which environmental factors play a key role. High altitude has already been established as a risk factor. Data from the CHD Registry in Riyadh were used to explore the impact of altitude throughout the Kingdom, including the mountain ranges of the south-west; 2,787 Saudi Arabian CHD cases were studied from 104 different cities and villages. Altitude was estimated using a geographical information system. The CHD “burden” was estimated by normalizing the number of CHD cases according to the city population. Cities at both the highest and the lowest altitudes displayed an increased CHD burden, indicating that CHD burden in Saudi Arabia is impacted by at least two different environmental factors — high altitude and coastal proximity. There is also an indication of a separate south-western influence which may reflect a unique cultural or genetic factor.