Extreme Obesity Can Cause Kidney Disease Especially In Elderly

Dr. Csaba P. Kovesdy

MedicalResearch.com Interview with:
Dr. Csaba P. Kovesdy, MD
Professor of Medicine
University of Tennessee Health Science Center
Chief of Nephrology
Memphis Veterans Affairs Medical Center

Medical Research: What is the background for this study? What are the main findings?

Dr. Kovesdy: Obesity has reached epidemic proportions in modern societies, and has been linked to adverse outcomes such as diabetes mellitus, hypertension, cardiovascular disease and mortality. In addition, obesity is also associated with chronic kidney disease through a variety of mechanisms. Our population is ageing, and previous studies have suggested that the effect of obesity on certain outcomes like mortality may be different in older vs. younger individuals, but this has not been previously examined for chronic kidney disease. We have this examined the association of granular BMI categories with progressive loss of kidney function in a very large cohort of patients with normal estimated GFR in patients of different ages. We found that the association of a BMI of >30 kg/m2 with progressive loss of kidney function was not present in younger individuals (< 40 years of age), and increased as people aged, with >80 years old displaying the strongest associations between obesity and loss of kidney function. In addition to this we also examined the association of BMI with mortality in different age groups, and found uniform U-shaped associations that did not vary by age.

Medical Research: What should clinicians and patients take away from your report?

Dr. Kovesdy: These results reinforce the widely held notion that extreme obesity can cause kidney damage. The novelty of these data is that it seems that oldest patients are most prone to such damage. This may be because ageing kidneys are more vulnerable to any kind of insult, or because older individuals have been exposed to the ill-effects of obesity for a much longer time, experiencing cumulative damage.

Medical Research: What recommendations do you have for future research as a result of this study?

Dr. Kovesdy: The observational nature of our data does not allow us to make concrete practice recommendations; that would require clinical trials of weight loss. Our data raises interesting questions about when weight loss interventions should commence: if the kidney damage in older individuals is due to the combined effects of age-related changes and obesity-related pathophysiology, then interventions could be effective at any age, and especially when started in the oldest individuals. If, on the other hand, kidney damage is more of a function of cumulative damage experienced over many decades, then interventions started at earlier ages, and maintained for a long time would be most effective. This dilemma will have to be answered by future interventional studies.

Another important practical point is the ideal BMI which is associated with the best clinical outcomes. In our population this was a BMI of 25-30 kg/m2. This range has been supported by several other studies in the recent past, and suggests that current guidelines about what an ideal BMI should be may need to be  re-evaluated in certain groups of patients.

Citation:

Association of age and BMI with kidney function and mortality: a cohort study

Jun Ling Lu, MD, Miklos Z Molnar, MD, Adnan Naseer, MD,Margit K Mikkelsen, Prof Kamyar Kalantar-Zadeh, MD,ProfCsaba P Kovesdy, MD

The Lancet Diabetes & Endocrinology Published Online: 30 July 2015

DOI: http://dx.doi.org/10.1016/S2213-8587(15)00128-X

[wysija_form id=”5″]

MedicalResearch.com is not a forum for the exchange of personal medical information, advice or the promotion of self-destructive behavior (e.g., eating disorders, suicide). While you may freely discuss your troubles, you should not look to the Website for information or advice on such topics. Instead, we recommend that you talk in person with a trusted medical professional.

The information on MedicalResearch.com is provided for educational purposes only, and is in no way intended to diagnose, cure, or treat any medical or other condition. Always seek the advice of your physician or other qualified health and ask your doctor any questions you may have regarding a medical condition. In addition to all other limitations and disclaimers in this agreement, service provider and its third party providers disclaim any liability or loss in connection with the content provided on this website.

 

 

Last Updated on August 21, 2015 by Marie Benz MD FAAD