Losing weight may preserve kidney function in obese people with kidney disease, according to a study appearing in an upcoming issue of the Clinical Journal of the American Society Nephrology (CJASN). The findings indicate that taking off the pounds could be an important step kidney disease patients can take to protect their health.

More than a third of US adults are either obese or overweight. Weight loss can improve a number of health problems; for example, it can improve control of diabetes, lower blood pressure and cholesterol levels, and reduce the effects of heart disease.

To see if losing weight might also have beneficial effects on the kidneys, Sankar Navaneethan, MD, (Cleveland Clinic), and his colleagues analyzed the studies that examined the effects of weight loss interventions in obese kidney disease patients. The investigators searched the medical literature and identified data from thirteen relevant studies that assessed the impact of diet, exercise, and surgical procedures on kidney function.

The analysis revealed that weight loss attained through diet and exercise reduces proteinuria (excess excretion of protein in the urine—a hallmark of kidney damage) and may prevent additional decline in kidney function in obese patients with kidney disease. Studies also showed that surgical interventions normalize the filtration rate of the kidneys in obese patients with high filtration rates (a risk factor for the development of kidney disease).

While the findings imply that weight reduction may prevent the progression of kidney disease in obese kidney disease patients, the authors noted that there were only a small number of studies available for analysis and additional high-quality long-term studies on this topic are needed.

The authors report no financial disclosures. Study co-authors include Hans Yehnert, MD (Acoma-Canoncito-Laguna Hospital); Fady Moustarah, MD, Philip Schauer, Martin Schreiber, MD (Cleveland Clinic); and Srinivasan Beddhu, MD (Salt Lake Veterans Affairs Healthcare System).

The article, entitled “Weight Loss Interventions in Chronic Kidney Disease: A Systematic Review and Meta-analysis,” will appear online at http://cjasn.asnjournals.org/ on Thursday, September 17, 2009, doi 10.2215/CJN.02250409.

Founded in 1966, the American Society of Nephrology (ASN) is the world’s largest professional society devoted to the study of kidney disease. Comprised of 11,000 physicians and scientists, ASN continues to promote expert patient care, to advance medical research, and to educate the renal community. ASN also informs policymakers about issues of importance to kidney doctors and their patients. ASN funds research, and through its world-renowned meetings and first-class publications, disseminates information and educational tools that empower physicians.

Source:  American Society of Nephrology (ASN)