Most of us have been committed to modern medicine as our life choice that gives true sense to our profession, aiming at continuing education and providing the best possible service and medical care on a daily basis.

In Croatia, medicine is at a very high professional level, as revealed by the activities of particular branch societies, e.g., Croatian Cardiac Society, Croatian Society of Hypertension, and Croatian Society for Nephrology, Dialysis and Transplantation of Croatian Medical Association as examples of highly prolific societies that stimulate excellence in both routine work and scientific research through international collaboration and innovativeness. This in turn favors introduction of the latest achievements in medicine and integration of applied science in daily routine, to the benefit of our patients. Medicine has long ceased to be an isolated and strictly separated profession, so that an individually applicable model of integrated different medical professions is now one of the main characteristics of modern medicine. Therefore, continuous knowledge refreshment and life-long education should be adopted as a necessary segment of the development of medicine in Croatia, along with promotion of clinical practice based on empirical knowledge.

Obesity is an omnipresent and topical problem all over the world; therefore, it is no surprise that obesity and kidney disease were the main topics of the World Kidney Day 2017 (1). Obesity is a condition of excessive accumulation of adipose tissue in the body with a number of adverse health sequels (2). In 2014, the World Health Organization reported alarming data pointing to the epidemic extent of obesity with more than 600 million adult persons facing this problem. In Europe, the prevalence of obesity is estimated to 4%-28% in male and 6.2%–36.5 % in female individuals. The Eurostat research published towards the end of 2016 has shown Croatia to rank eighth among the 28 European Union member countries according to the prevalence of obese persons (18.7%); the prevalence of obesity increases with age (25% of persons aged 45-72 are overweight) and shows male predominance (20.7% of men and 16.8% of women are obese). What is most disturbing is the high prevalence of obesity in young age groups, children in particular (8.8%) (3). Therefore, correct and timely recognition of the problem and ensuring appropriate treatment in childhood and adolescence is of utmost importance, along with follow up and necessary modifications in adulthood. Body mass index >25 kg/m² is directly associated with the risk of developing chronic kidney disease (obesity induced glomerulosclerosis), while cardiovascular mortality and various comorbidities are also increased in obese individuals (4-7).

One should not neglect the fact that obesity is a preventable risk factor for development of cardiovascular disease, diabetes mellitus, dyslipidemia, arterial hypertension, chronic kidney disease, etc.; therefore, professional debate and analysis of the issue, its causes, sequels and optimal therapies should remain in the focus of our professional interest and efforts. Promoting healthy lifestyle and habits, and continuing education for prevention and raising public awareness of the issue must be the key priorities in our daily work with patients.

Considering the facts and circumstances mentioned above, and in continuation to the World Kidney Day held on March 9, 2017 (1), it is my great honor to be guest editor of this special issue of the Cardiologia Croatica journal. Our joint intention is to provide, through collaboration of various professions (pediatric and adult cardiologists and nephrologists, as well as public health professionals), a survey and latest concepts on the association between obesity and health of the brain, heart and kidney. A comprehensive and interdisciplinary approach to the prevention of renal and cardiovascular diseases is necessary from childhood to adult age. Accordingly, papers appearing in this issue have been chosen so as to point to the applicability of particular options in daily routine of not only cardiologic and nephrologic professions, but also in the work of family medicine, nurses and medical technicians, medical students, and all other healthcare workers.

The contributions from the authors are greatly appreciated indeed. Special thanks go to the journal Editorial Board led by Assist Prof Ivanuša, PhD, for having recognized the topical importance of the issue of obesity and obesity related diseases, with special reference to the nephrologic-cardiologic association in childhood and adult age. I believe that all of us involved in the publication of this special issue of Cardiologia Croatica will be happy if this issue shows to be the preferred reading for medical students and medical professionals they will turn to all over again.