Background: Obesity is a risk factor for both chronic kidney disease (CKD) and cardiovascular disease. The association of simple indices of obesity with CKD remains poorly understood. Evidence suggests that measures of central obesity such as waist circumference (WC) and waist-to-hip ratio (WHR) are more accurate predictors of morbidity and cardiovascular risk than body mass index (BMI). This study aimed to investigate the association of BMI, WC and WHR with CKD risk in a population screened for type 2 diabetes.
Methods: Data were drawn from a population-based screening programme of 6475 volunteers without pre-existing diabetes. A number of investigations and cardiovascular health-related assessments were performed. Participants were categorized into two groups: those with an estimated glomerular filtration rate (eGFR) ≥60 and <60 mL/min/1.73m(2). Participants were also categorized as low, medium and high risk according to each anthropometric variable.
Results: CKD was independently associated with higher WC and BMI (P < 0.01) but not WHR (P = 0.47). Increasing obesity measured by BMI and WC was associated with a reduction in eGFR for both men and women (P < 0.001). Increasing risk categories for BMI and WC were also associated with lower eGFR in men and women (P < 0.001). Combining anthropometric measures provided no additional measure of risk for underlying CKD.
Conclusions: WC may be a simple and reliable clinical tool for the detection of underlying CKD within primary care. Given the complex interaction between adiposity and uraemia, a combined screening tool using BMI and WC or WHR is unlikely to provide any additional benefit to risk analysis.