A range of surgical and non-surgical weight-loss interventions were assessed. All interventions, when taken together, resulted in significant reduction in weight among CKD patients. This was associated with a reduction in urinary protein excretion (described in two studies) but no overall effect on the GFR, possibly due to the short term nature of the studies. Effects on BP were not reported in the RCTs, whereas the observational studies reported consistently large, significant reductions in BP compared to baseline with both non- surgical weight loss (weighted mean difference in BP 9.0 mm Hg; 95% CI 3.7 14.2 mm Hg; Po0.0001) as well as surgical weight loss (weighted mean difference, 22.6 mm Hg; 95% CI 19.1 26.2; Po0.0001). Thus, weight loss likely improves BP in patients with CKD, although high-quality RCTs are needed to confirm this finding. Body weight and outcomes. In the general population, overweight and obesity have been clearly shown to be associated with an increased risk of cardiovascular events and A J-curve relationship has been described in many reports, revealing an increased risk in underweight individuals (e.g., those with a BMI o18.5) as well. RCTs have demon- strated that weight loss reduces the incidence of diabetes,55 but any beneficial effects on cardiovascular outcomes or survival remain to be proven. Indeed, a number of RCTs involving use of pharmacological agents to induce weight loss have been stopped early owing to unintended and unanticipated adverse effects of the agent being assessed (e.g., rimonabant and The data are less clear for patients with CKD. Obesity has been proposed as a possible potentiator of CKD progression; however, reliable data remain sparse. 