The authors conclude that being overweight is not without risk, and their findings come after other estimates see the burden of chronic kidney disease increasing in the United States.
The debate goes on whether one can be overweight and otherwise healthy, but a new study from South Korea finds that patients carrying extra weight were at higher risk of chronic kidney disease (CKD), even if they were in good metabolic health.
Research published in the Annals of Internal Medicine examined a cohort of 62,249 young and middle-aged men and women who were metabolically healthy and who did not have either CKD or proteinuria at baseline. After a follow-up of 369,088 person-years (or 5 years), 906 cases of CKD were found. Researchers categorized each case of incident CKD by level of body mass index (BMI).
It is important to note that this study used different definitions of “overweight” and “obese” than are used in the United States, where CDC lists persons with BMI of 25 mg/k2 as overweight, and obesity is defined as having a BMI of 30 mg/k2 or greater. In this study, participants with a BMI of 23 to 24.9 were deemed overweight, and those with BMI over 25 were deemed obese.
In cases per 1000 participants, there were -4.0 (95% confidence interval [CI], -7.8 to -0.3) in those underweight, or BMI less than 18.5; 3.5 (95% CI, 0.9 to 6.1) in those overweight, and 6.7 (95% CI, 3.0 to 10.4) in those who were obese.
According to the authors, the findings show “metabolically healthy obesity is not a harmless condition,” and “the obese phenotype, regardless of metabolic abnormalities, can adversely affect renal function.”
A study published in April 2015 found that the incidence of CKD in the United States is rising, attributed in part to the overall rise in diabetes and obesity. A statistical model published in the American Journal of Kidney Diseases predicted that the share of adults over age 30 that would have CKD would increase from 13.2% to 16.7% by 2030.
CKD is a among the more expensive conditions for health plans to treat.
Chang Y, Ryu S, Choi Y, et al. Metabolically healthy obesity and development of chronic kidney disease: a cohort study [published online February 9, 2016]. Ann Intern Med. 2016; doi:10.7326/M15-1323.