Cross-sectional and prospective follow-up study to detect early signs of cardiac dysfunction in obesity: protocol of the CARDIOBESE study

INTRODUCTION: In view of the increasing occurrence of both obesity and heart failure, a growing overlap of these two clinical entities in the near future is expected. Significant advances in our understanding of the pathophysiological consequences of obesity for the cardiovascular system have been made over the past two decades. However, to optimise management and treatment of obesity patients, further research is required to improve early identification of cardiac dysfunction in obesity and to gain insight in the underlying pathophysiology. The CARdiac Dysfunction In OBesity – Early Signs Evaluation (CARDIOBESE) study has been designed to address these issues. METHODS AND ANALYSIS: CARDIOBESE is a cross-sectional multicentre study of 100 obesity patients scheduled for bariatric surgery (body mass index (BMI) ≥35 kg/m(2)) without known cardiovascular disease, and 50 age-matched and gender-matched non-obese controls (BMI <30 kg/m(2)). Echocardiography, blood and urine biomarkers and Holter monitoring will be used to identify parameters that are able to show cardiac dysfunction at a very early stage in obesity patients (primary objective). Furthermore, a prospective follow-up study of obesity patients before and 1 year after bariatric surgery will be done to gain insight in the pathophysiology of obesity causing cardiac dysfunction (secondary objective). ETHICS AND DISSEMINATION: The study was approved by the Medical Ethics Committee Toetsingscommissie Wetenschappelijk Onderzoek Rotterdam e.o. (TWOR). Inclusion of patients and controls is almost complete. Analyses of the investigations are currently being performed, and dissemination through peer-reviewed publications and conference presentations is expected from the first quarter of 2019. By identifying early markers of cardiac dysfunction in obesity, and by understanding the underlying pathophysiology of the abnormalities of these markers, the CARDIOBESE study may provide guidance for risk stratification, monitoring and treatment strategies for obesity patients.