High BMI appears to lower death risk in those at high risk for renal disease.
High BMI in patients at high risk for kidney disease seems to be associated with a reduced likelihood of death, researchers suggest.
Lead investigator Claudine Jurkovitz, MD, MPH, who is a nephrologist and the Director of Operations for Christiana Care Center for Outcomes Research in Newark, Del., said obesity is a known mortality risk factor in the general population, but high BMI paradoxically is associated with reduced mortality in dialysis patients.
She and her colleagues examined the effect of obesity on mortality in the National Kidney Foundation Early Evaluation Program (KEEP) population. The KEEP Study is a screening program for kidney disease that enrolled individuals 18 years and older with a family history of kidney disease or a personal history of diabetes or hypertension.
Dr. Jurkovitz’s group defined obesity as a BMI of 30 kg/m2 or greater and CKD as an albumin:creatinine ratio of 30 mg/g or greater or a calculated glomerular filtration rate (GFR) less than 60 mL/min/1.73 m2.
Among the 33,474 participants, 44.6% had a BMI of 30 kg/m2 or greater, 30.7% had diabetes and 78.4% had hypertension. The total death rate for the group was 4.83 per 1000 person-years, but it was 3.96 per 1000 person-years for obese individuals and 5.53 per 1000 person-years for non-obese subjects.
The adjusted risk of death was 28% lower for obese patients compared with non-obese individuals. Further analyses, how-ever, revealed that the results differ if the patients have any chronic disease (including CVD, diabetes, or kidney disease) or no chronic disease.