Obesity has long been linked to heart disease, high blood pressure, and diabetes. Now, researchers are adding kidney failure to the list of ailments, as a new research has found that obese people have up to a seven times greater risk of developing end-stage renal disease, more simply known as kidney failure, than normal weight people.
The study, by researchers from the University of California-San Francisco and Kaiser Permanente of Northern California Division of Research, is based on data derived from over 320,000 Northern California Kaiser members whose height and weight were measured during health checkups between 1964 and 1985.
Cases of end-stage renal disease were determined using the U.S. Renal Data System, a comprehensive national registry that collects and disseminates information on end-stage renal disease, and it was noted that a total of 1,471 cases of end-stage renal disease occurred among study participants during an average follow-up period of about 26 years.
As a part of the study researchers calculated the body mass index (BMI) of study participants and found that those with a higher BMI were at greater risk of kidney failure.
Chi-yuan Hsu, MD, UCSF assistant professor of medicine and lead author of the study said that it had demonstrated that people who were obese or overweight faced a higher risk of renal failure, and added that the risk of kidney failure among ‘overweight’ study participants was 1.87 times that of normal weight participants, or nearly 90 percent greater.
There are more and more people with kidney failure, but it hasn’t been appreciated much that kidney failure can be a consequence of obesity. We think this study is important because it demonstrates quite convincingly that people who are obese or overweight are at much higher risk of kidney failure. If you are mildly overweight, not even frankly obese, you are roughly 90 percent more likely to develop end-stage renal failure, he said.
Dr Hsu further said that one reason for the higher rate of kidney failure among obese patients might be that they are more likely to develop diabetes and hypertension. It was also noted that obesity places more metabolic demand on the kidneys, forcing them to work harder.
As the person gets bigger, hyper-filtration occurs and this over filtration is what tears the kidneys down, he added.
The study is published in the January issue of the Annals of Internal Medicine.