Literature Highlight: Radiation Exposure to the Heart and the Risk of Ischemic Heart Disease

A multinational, population-based, casecontrol study was performed to evaluate the effect of cardiac radiation exposure on IHD risk. All women who received radiotherapy and were registered in the Swedish National Cancer Register (diagnosed between 1958 and 2001; younger than seventy years of age) or the Danish Breast Cancer Cooperative Group (diagnosed between 1977 and 2000; younger than seventy-five years of age) were reviewed for inclusion in the study. Women diagnosed with unilateral non-metastatic breast cancer, with no previous exposure to radiotherapy or history of major coronary events, were included in the study (n=2168). Women who had documented major coronary events (myocardial infarction, coronary revascularization, or death from IHD) were classified as cases (n=963). Controls (n=1205) were matched by country of residence (one per case in Sweden; two per case in Denmark), receipt of radiotherapy, and age of both at cancer diagnosis and year of diagnosis within 5 years.