High body mass index (BMI) may identify patients who are at increased risk of progressive chronic kidney disease (CKD), British researchers reported at the 52nd congress of the European Renal Association-European Dialysis and Transplant Association in London.
Rupert W. Major, MBChB, a Kidney Research U.K. Fellow at the University of Leicester in the U.K., and colleagues studied a cohort of 31,274 patients with an estimated glomerular filtration rate (eGFR) below 60 mL/min/1.73 m2 (mean 51.1) as calculated using the Modification of Diet in Renal Disease study equation. Of these patients, 64.7% had 2 eGFR results more than 3 months apart. The cohort had a mean BMI of 28.2 kg/m2, and 28.7%, 38.8%, and 30.8% had a BMI of 18–25 (normal), 25-30 (overweight), and greater than 30 kg/m2 (obese or severely obese). Results showed that the mean decline in eGFR was greater in the higher BMI categories.
The mean eGFR declined by 0.11 and 0.08 mL/min/1.73 m2 per year in patients with a BMI of 30–35 and greater than 35 kg/m2, respectively, compared with no change or even slight increases in eGFR in the other BMI categories. The decline in eGFR in the higher BMI categories was especially pronounced in younger patients with higher levels of proteinuria, according to the investigators.
“The association we found suggests that reducing BMI might slow the progression of CKD,” Dr. Major told Renal & Urology News. “Lifestyle interventions, such as exercise and dietary programs, are potential areas for intervention in this area, particularly in primary care. At the University of Leicester, and other international renal research centers, we are running structured exercise program clinical trials in CKD to investigate the effect on outcomes, including CKD progression.”
Dr. Major noted that previous studies have focused on the relationship of BMI and the diagnosis of CKD, including a study by his colleagues suggesting that waist circumference may be a potential CKD screening tool. In contrast, the current study, funded by the U.K.’s National Institute for Health Research, focused on progression of disease in patients with known CKD, and the study included what is probably the largest cohort to date to examine the association, he said.