Effect of weight loss using formula diet on renal function in obese patients with diabetic nephropathy

Abstract

Objective: To evaluate the effect and safety of treatment with low-calorie formula diet on renal function and proteinuria in obese patients with diabetic nephropathy.

Design: Prospective study on safety and efficacy of a 4-week low-calorie (11-19 kcal/kg/day) normal-protein (0.9-1.2 g/kg/day) diet partly supplemented with formula diet.

Subjects: In all, 22 obese patients with diabetic nephropathy (BMI: 30.4+/-5.3 kg/m(2), HbA1c: 7.1+/-1.4%, serum creatinine: 172.4+/-57.5 micromol/l, urinary protein: 3.3+/-2.6 g/day).

Results: The mean body weight decreased by 6.2+/-3.0 kg. The mean systolic blood pressure, creatinine, blood urea nitrogen, urinary protein, and 8-hydroxydeoxyguanosine decreased significantly by 7.5+/-12.7 mmHg, 41.6+/-23.9 micromol/l, 1.50+/-1.61 mmol/l, 1.8+/-1.7 g/day, and 3.1+/-3.6 ng/mg creatinine, respectively. No patient had increased serum creatinine and urinary protein. Mean creatinine clearance (40.6+/-17.9 to 46.1+/-14.6 ml/s/1.73 m(2)) and serum albumin showed no significant changes. Delta serum creatinine and Delta urinary protein correlated with Delta body weight (r=0.62 and 0.49, respectively) and Delta visceral fat area (r=0.58 and 0.58, respectively), but did not correlate with Delta systolic blood pressure, Delta fasting blood glucose and Delta subcutaneous fat area.

Conclusion: These results suggested that weight reduction using formula diet might improve renal function and proteinuria safely for a short term in obese patients with diabetic nephropathy.