Obesity and metabolic disorders are known risk factors for impaired renal function.

The objective of this study is to determine the nature of the interactive effect between obesity and metabolic profile on the increase in urinary albumin excretion and the decrease in estimated glomerular filtration rate (eGFR) in hypertensive patients.

This is a prospective cross-sectional study, which involved a population of 499 hypertensive subjects. Based on BMI values and metabolic profile, subjects were classified into four metabolic phenotype groups: group I: metabolically healthy non-obese (MHNO), group II: metabolically healthy but obese (MHO), Group III: metabolically unhealthy non-obese (MUHNO) and group IV: metabolically unhealthy obese (MUHO). The effect of the biological interaction between obesity and metabolic profile on impaired renal function was tested on both scales: multiplicative and additive.

A significant difference in renal function was noted between the four groups. After adjustment for confounding factors, patients who are both obese and at metabolic risk (MUHO) have the highest risk of microalbuminuria and decreased eGFR (OR=6; 95CI%[2.7–13], OR=5.4; 95CI%[1.1–26] respectively). Analysis of the additive biological interaction shows that 51% and 53% of the risk of elevated ACR and high ACR-low DFGe association respectively is explained by the obesity-metabolic disorder association. The interaction mechanism is synergistic (SI=2.6; 95CI%[1.2–5.3]).

The decline in renal function in hypertensive subjects is significantly associated with the interaction of obesity and metabolic disorders. The management of these at-risk subjects must include, in addition to the therapeutic regimen, a dietary and physical program to preserve glomerular function.