MedicalResearch.com Interview with: Minna Johansson, PhD student Department of Public Health and Community Medicine, Institute of Medicine The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Research Unit and Section for General Practice, Vänersborg, Sweden Medical Research: What is the background for this study? What are the main findings? Response: The decision to introduce screening for abdominal aortic aneurysms (AAA) was based on four randomised controlled trials from the 1980s and 1990s that showed a 50% relative risk reduction in aneurysm-related mortality. Over the last 15 years Sweden, the UK and the USA have introduced AAA screening programmes. However, abdominal aortic aneurysms screening does not only have intended benefits but also unintended harms. The most important harm is overdiganosis; i.e. the overdetection of aneurysms that would not have caused symptoms in that man´s remaining life, nor been the cause of his death. In this study, we estimate that 176 of every 10,000 men invited to screening are overdiagnosed as a consequence of screening. These men are unnecessarily turned into patients and may experience appreciable anxiety throughout their remaining lives. Moreover, 37 of these men unnecessarily have preventive surgery and 1.6 of them die as a consequence. Furthermore, a recent drop in abdominal aortic aneurysms prevalence by over 70% reduces the potential benefits of AAA screening. Unfortunately, the harms are not likely to be reduced by the same rate, thus leading to a worsened benefit:harm ratio. This means that the benefit:harm ratio is likely to be worse in current screening programmes than in the trials on which they were based. Additionally, it has been proposed to lower the cut-off for the abdominal aortic aneurysms-diagnosis from 30 to 25 mm. Our estimates show that such a change of definition would increase the rate of overdiganosis substantially and further worsen the benefit:harm ratio of abdominal aortic aneurysms screening. (more…)