Weight loss interventions in chronic kidney disease: a systematic review and meta-analysis

Abstract

Background and objectives: Obesity is an independent risk factor for development and progression of chronic kidney disease (CKD). We conducted a systematic review to assess the benefits of intentional weight loss in patients with non-dialysis-dependent CKD and glomerular hyperfiltration.

Design, setting, participants, & measurements: We searched MEDLINE, SCOPUS, and conference proceedings for randomized, controlled trials and observational studies that examined various surgical and nonsurgical interventions (diet, exercise, and/or antiobesity agents) in adult patients with CKD. Results were summarized using random-effects model.

Results: Thirteen studies were included. In patients with CKD, body mass index (BMI) decreased significantly (weighted mean difference [WMD] -3.67 kg/m(2); 95% confidence interval [CI] -6.56 to -0.78) at the end of the study period with nonsurgical interventions. This was associated with a significant decrease in proteinuria (WMD -1.31 g/24 h; 95% CI -2.11 to -0.51) and systolic BP with no further decrease in GFR during a mean follow-up of 7.4 mo. In morbidly obese individuals (BMI >40 kg/m(2)) with glomerular hyperfiltration (GFR >125 ml/min), surgical interventions decreased BMI, which resulted in a decrease in GFR (WMD -25.56 ml/min; 95% CI -36.23 to -14.89), albuminuria, and systolic BP.

Conclusions: In smaller, short-duration studies in patients with CKD, nonsurgical weight loss interventions reduce proteinuria and BP and seem to prevent further decline in renal function. In morbidly obese individuals with glomerular hyperfiltration, surgical interventions normalize GFR and reduce BP and microalbuminuria. Larger, long-term studies to analyze renal outcomes such as development of ESRD are needed.

Figures

Figure 1.

Flow chart showing number of citations retrieved by individual searches and number of trials included in the review.

Figure 2.

Effect of nonsurgical interventions on GFR in CKD.

Figure 3.

Effect of nonsurgical interventions on urinary protein excretion in CKD.

Figure 4.

Effect of surgical interventions on glomerular hyperfiltration.