According to a study published in Annals of Internal Medicine, patients who are overweight or obese, even in the absence of metabolic abnormalities, are at increased risk for chronic kidney disease (CKD). These results offer more evidence that "metabolically healthy obesity" is not a harmless condition. CKD is a precursor for end-stage renal disease and a strong risk factor for cardiovascular morbidity and mortality. Its prevalence is increasing worldwide along with the growing prevalence of obesity and metabolic disease. While obesity with associated metabolic risk factors (hypertension, insulin resistance, hyperglycemia, dyslipidemia) has been identified as a major risk factor for CKD, whether there is a link between metabolically healthy obesity (being obese without associated metabolic abnormalities) and CKD is not known.

Researchers studied a large cohort of young to middle-aged South Korean men and women who were metabolically healthy and without CKD or proteinuria to assess the risk for CKD for patients in various body mass index (BMI) categories. The researchers found that being overweight or obese was associated with increased CKD incidence. These findings show that metabolically healthy obesity is not a harmless condition and that being overweight, regardless of metabolic abnormalities, can adversely affect renal function.

Research: Metabolically Healthy Obesity and Development of Chronic Kidney Disease: A Cohort Study, Yoosoo Chang, MD, PhD; Seungho Ryu, MD, PhD; Yuni Choi, BS; Yiyi Zhang, PhD; Juhee Cho, PhD; Min-Jung Kwon, MD, PhD; Young Youl Hyun, MD, PhD; Kyu-Beck Lee, MD, PhD; Hyang Kim, MD, PhD; Hyun-Suk Jung, MD; Kyung Eun Yun, MD, PhD; Jiin Ahn, MSPH; Sanjay Rampal, MD, PhD; Di Zhao, PhD; Byung-Seong Suh, MD, PhD; Eun Cheol Chung, MD, PhD; Hocheol Shin, MD, PhD; Roberto Pastor-Barriuso, PhD; and Eliseo Guallar, MD, DrPH, Annals of Internal Medicine, doi:10.7326/M15-1323, published online 9 February 2016.