BMI is associated with the development of chronic kidney diseases in hypertensive patients with normal renal function

We aimed to investigate the relationship of BMI and waist circumference with the development of chronic kidney disease (CKD).

A total of 12 672 hypertensive patients with estimated glomerular filtration rate (eGFR) at least 60 ml/min per 1.73 m from the renal sub-study of the China Stroke Primary Prevention Trial (CSPPT) were included. The primary outcome was the development of CKD, defined as a decrease in eGFR of at least 30% and to a level of less than 60 ml/min per 1.73 m at the exit visit, or end-stage renal disease. A secondary outcome was rapid renal function decline, defined as an average decline in eGFR of at least 5 ml/min/1.73 m per year.

Over a median follow-up of 4.4 years, the risk of the primary event (per 1 kg/m increment; OR = 1.07, 95% CI 1.02-1.14) or rapid renal function decline (per 1 kg/m increment; OR = 1.05, 95% CI 1.01-1.08) increased with each increment of BMI. Consistently, compared with those with normal weight (BMI <24.0 kg/m), participants with obesity (BMI ≥28.0 kg/m) had an increased risk of the primary event (OR = 1.82; 95% CI 1.15-2.90) and rapid renal function decline (OR = 1.26; 95% CI 0.95-1.67). However, waist circumference had no obvious effect on the risk of the primary event (per 5 cm increment: OR = 0.94, 95% CI 0.85-1.04) or rapid renal function decline (OR = 0.96, 95% CI 0.90-1.03).

Higher BMI, but not waist circumference, was significantly associated with an increased risk of CKD development in hypertensive patients with normal kidney function.