KI Reports and World Kidney Day.

Recent data from the Global Burden of Disease project provide alarming statistics about the rapidly growing burden of chronic kidney disease (CKD) in the world. The data from the Global Burden of Disease project reveal a dramatic increase (90%) of global years of life lost to CKD from 1990 to 2013; it is now the 13th leading cause of death worldwide. CKD, which results in almost 1 million deaths annually, is only one of 3 diseases in which standardized death rates have increased since 1990 (the other 2 being HIV/AIDS and diabetes). The number of years patients have lived with a disability related to CKD also increased by 49.5% during the same period. Despite these dramatic increases, the Global Burden of Disease project estimates do not include rates of acute kidney injury, nor do they account for the increase in cardiovascular disease and other medical conditions that result from having impaired kidney function. The absence of these data suggests that the true burden of kidney disease worldwide may be larger than is currently estimated. In fact, CKD is also no longer limited to the developed world; it is now one of the top 5 causes of death in numerous countries in Central America, including Mexico, Barbados, Costa Rica, and Nicaragua.

The burden of CKD is likely to rise further throughout the world given that more than one third of the world’s male and female population is now either overweight or obese (see Figures 1 and 2), as measured by an elevated body mass index. The elevated body mass index is associated with physiological and structural changes in the kidney, which frequently leads to hypertension and diabetes, and increases the risk for CKD and end-stage renal disease.3, 4, 5 Thus, obese patients are more likely to develop kidney stones, proteinuria, renal injury with elevated microalbuminuria, diabetic and hypertension-associated kidney disease, obesity-related focal and segmental glomerulosclerosis/glomerulopathy, and renal cell carcinoma. Preliminary data show that many of these diseases may be reversed or stabilized with weight loss.7, 8, 9

Figure 1

Prevalence of obesity in males aged 18+, 2014 (age standardized estimate).

Figure 2

Prevalence of obesity in females aged 18+, 2014 (age standardized estimate).

Kidney International (KI) Reports, which launched in May 2016, is firmly committed to addressing the increasing global burden of kidney disease including CKD by creating a platform for the best clinical and translational research in nephrology that permits easy access to clinician and researchers worldwide.

In this issue, we celebrate World Kidney Day by publishing expert reviews on 3 aspects of obesity and kidney disease. In the first review, Tsuboi et al. discuss the pathology of kidney disease in obesity. Obesity-related glomerulopathy exemplifies hyperfiltration-related kidney injury; kidney biopsy findings in obese patients with proteinuria with or without CKD include glomerulomegaly with or without focal segmental glomerulosclerosis. In the second article, the benefit of bariatric surgery is critically examined by Chang et al. Although bariatric surgery for weight loss has been shown to decrease microalbuminuria as well as lower the risk of kidney decline and end-stage renal disease, the health risks are significant and the long-term effects are still being investigated. The last article in this series, by Kalantar-Zadeh et al., addresses the apparent paradox that being overweight may not necessarily be detrimental; in fact, it could provide some survival advantages for patients with CKD.

Obesity, diabetes, and hypertension—lifestyle diseases that can lead to kidney decline—are on the rise in both developed countries and resource-poor countries where the treatment of end-stage renal disease may not be widely available. Preventive efforts should be made as early as possible in overweight patients at risk for kidney disease, especially those with diabetes and hypertension, including careful monitoring for renal complications.

World Kidney Day is our annual reminder for bringing attention to disease awareness, prevention, and improved options for patients who bear the burden of CKD. As a new open access journal that provides clinically relevant content to medical professionals worldwide free of charge, KI Reports is proud to play a role in spreading the word about recent developments in this field.

Disclosure

The authors declared no competing interests.