Central obesity associates with renal hyperfiltration in the non-diabetic general population: a cross-sectional study

BMC Nephrol. 2016 Nov 10;17(1):172. doi: 10.1186/s12882-016-0386-4.

Abstract

Background: Obesity is a risk factor for end-stage renal disease. Renal hyperfiltration, defined as an abnormally high glomerular filtration rate (GFR), is a link in the causal chain between diabetes and chronic kidney disease. Whether obesity is associated with hyperfiltration in the non-diabetic general population, remains unresolved due to a lack of consensus regarding the definition of hyperfiltration and the limited precision of high-range GFR estimations with creatinine and/or cystatin C.

Methods: 1555 middle-aged participants without diabetes, renal or cardiovascular disease were enrolled from the general population in the Renal Iohexol Clearance Survey from the 6th Tromsø Study (RENIS-T6) between 2007 and 2009. Obesity was assessed using the body mass index (BMI), waist circumference (WC) and the waist-hip ratio (WHR). GFR was measured by iohexol clearance. Dichotomous variables for hyperfiltration were based on two alternative definitions using unadjusted GFR (mL/min) above the 90th percentile. The 90th percentile was age-, sex- and height-specific in one definition and age-, sex-, height- and weight-specific in the other.

Results: In multivariable adjusted logistic regression models, only WHR was consistently associated with hyperfiltration based on both definitions. For the definition based on the age-, sex-, height- and weight-specific 90th percentile, the association with the WHR (odds ratios (95 % confidence intervals)) for hyperfiltration was 1.48 (1.08-2.02) per 0.10 WHR increase.

Conclusions: Central obesity is associated with hyperfiltration in the general population. The WHR may serve as a better indicator of the renal effects of obesity than BMI or WC.

Keywords: Body mass index; Chronic kidney disease; Glomerular filtration rate; Glomerular hyperfiltration; Waist circumference; Waist-hip ratio.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Body Mass Index
  • Cross-Sectional Studies
  • Female
  • Glomerular Filtration Rate
  • Humans
  • Kidney / physiopathology*
  • Male
  • Middle Aged
  • Obesity, Abdominal / physiopathology*
  • Waist Circumference
  • Waist-Hip Ratio