Obesity May Up Risk of Kidney Failure
Study: Kidney Failure May Be 3 Times as Likely With Obesity
May 22, 2006 -- New research shows that people who have ever been obese may be more likely to develop chronic kidney failurekidney failure (chronic renal failure, or CRF).
“ObesityObesity seems to be an important -- and potentially preventable -- risk factor for CRF,” write Elisabeth Ejerblad, MD, and colleagues in June’s Journal of the American Society of Nephrology.
Ejerblad works at Sweden’s Karolinska Institute. Her study included 926 people with chronic kidney failure and 998 people of similar backgrounds without chronic kidney failure. Among the findings:
- Being overweight at age 20 tripled the odds of chronic kidney failure.
- Men who had ever been obese and women who had ever been very obese were 3 to 4 times as likely as those who had never been obese to have CRF.
About Kidney Failure
Here’s how the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), a branch of the National Institutes of Health, describes the kidneys and kidney failure:
- The kidneys are a pair of bean-shaped organs, each about the size of a fist, in the middle of the back, just below the rib cage.
- The kidneys filter waste products and extra water out of the blood; those waste products and water become urine.
- Kidneys may fail suddenly (acute kidney failure) or gradually.
- Chronic kidney failure is the gradual loss of kidney function.
- Total or near-total kidney failure is called end-stage renal disease, which requires kidney dialysis or transplantation.
The early stages of kidney diseasekidney disease may not show symptoms. The first signs may include frequent headaches or feeling tired or itchy all over your body. Those symptoms aren’t unique to kidney failure and may or may not indicate kidney failure.
The NIDDK lists these possible symptoms of worsening kidney failure:
- Needing to urinate more or less often
- Appetite loss or nausea and vomiting
- Swollen or numb feet and hands
- Feeling drowsy or having trouble concentrating
- Darkening skin
- Muscle cramps
Doctors may test blood and urine samples to look for signs of kidney problems.
Studying Kidney Failure
Participants in Ejerblad’s study were in their late 50s, on average, and lived in Sweden.
Most had ‘moderately severe’ chronic kidney failure, the researchers write. The study doesn’t show that any of the patients had end-stage renal disease or were on dialysis.
Participants completed mailed questionnaires covering these topics:
- Current weight
- Weight at 20, 40, and 60 years
- Highest lifetime weight
- Alcohol consumption
- Tobacco use
Participants were also interviewed in person and had their medical records checked. The researchers calculated participants’ body mass index (BMI)body mass index (BMI), which is based on height and weight.
BMI of 30 or more is considered obese. BMI of at least 25 but less than 30 is considered overweight. There are other ways to measure obesityobesity, but this study (like many others) only tracked BMI.