Objective: We aimed to investigate the relationship of BMI and waist circumference with the development of chronic kidney disease (CKD).
Methods: 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.
Results: 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).
Conclusion: Higher BMI, but not waist circumference, was significantly associated with an increased risk of CKD development in hypertensive patients with normal kidney function.