Table 1.
Characteristics of studies that analyzed the effects of dietary and pharmacologic interventions to reduce weight on renal parameters
| Reference | Type of Study | Baseline Kidney Disease | Preintervention BMI (kg/m2) | Comorbidities | No. of Patients | Intervention | Follow-up | Renal Outcomes | Nonrenal Outcomesa |
|---|---|---|---|---|---|---|---|---|---|
| Observational | |||||||||
| Cook et al. (24), 2008 | Prospective cohort | Stage 2 through 4 CKD and ESRD | 35.7 ± 4.5 | NA | 44 (total) 19 (predialysis) 22 (dialysis) 3 (transplant) |
Hypocaloric (500 kcal less than usual), low-fat, renal diet plus exercise 3×/wk plus orlistat 120 mg thrice daily | 12 mo | eGFR | Exercise capacity, functional ability |
| Saiki et al. (21), 2005 | Prospective cohort | Creatinine <265 mmol/L and proteinuria >300 mg/d | 30.4 ± 5.3 | Diabetes | 22 | Hypocaloric diet (11 to 19 kcal/kg per d) using formula diet | 4 wk | 24-h creatinine clearance, 24-h proteinuria | Lipid profile, HbA1c, visceral fat analysis using CT scan |
| Solerte et al. (22), 1989 | Prospective cohort | Proteinuria >500 mg/d | 33.5 ± 1.6 | Diabetes, retinopathy | 24 | Hypocaloric diet (1410 kcal/d) | 12 mo | GFR (Tc injection), 24-h creatinine clearance, 24-h proteinuria | Lipid profile, BP, HbA1c |
| Vasquez et al. (25), 1984b | Prospective cohort | Proteinuria | 36.1; 47.6; 39.1 | Normal, borderline diabetes | 37 | Hypocaloric diet (500 kcal/d less than usual) | 82 to 110 d | Serum creatinine, 24-h proteinuria | BP, albumin, liver function tests |
| Randomized | |||||||||
| Morales et al. (20), 2003 | Randomized study | Proteinuric nephropathies with Cr <2.0 mg/dl | 33 ± 3.5 | Diabetes, hypertension | 30 | Hypocaloric diet (500 kcal less than usual); protein intake 1.0 to 1.2 g/kg per d versus usual dietary intake | 5 mo | CG creatinine clearance, 24-h proteinuria | Lipid profile |
| Praga et al. (23), 1995c | Randomized study | Proteinuria (>1 g/d) with Cr 0.8 to 2.3 mg/dl | 37.1 ± 3.1 | Hypertension | 17 | Hypocaloric diet (1000 to 1400 kcal/d) versus captopril 50 to 150 mg/d | 12 mo | 24-h creatinine clearance, 24-h proteinuria | Lipid profile |
CG, Cockcroft-Gault; Cr, creatinine; CT, computed tomography; eGFR, estimated GFR.
a
All studies measured BMI and change in weight over time.
b
Proteinuria data from these studies were not included in the analysis because of the lack of adequate information. This study had three arms: Normal control subjects, patients with borderline diabetes, and patients with type 2 diabetes.
c
We used the pre- and postintervention data from the hypocaloric arm only for the analysis.