Hyperleptinaemia, insulin resistance and survival in peritoneal dialysis patients

Association between the geriatric nutritional risk index and clinical outcomes among peritoneal dialysis patients: A meta-analysis

BACKGROUND

To identify the relationship between the geriatric nutritional risk index (GNRI) and clinical outcomes in patients receiving peritoneal dialysis (PD).

METHODS

The PubMed, EBASE, Web of Science and CNKI databases were searched for available studies up to December 25, 2023. The primary outcome was all-cause mortality, and the secondary outcomes included the incidence of PD dropout, major adverse cardiac and cerebrovascular events (MACCEs), technique failure and peritonitis. Hazard ratios (HRs) and 95% confidence intervals (CIs) were combined to evaluate the predictive value of the GNRI for the occurrence of the above endpoints.

RESULTS

Ten cohort studies with 3897 patients were included. The pooled results demonstrated that a lower GNRI was significantly associated with a greater incidence of all-cause mortality (HR = 0.71, 95% CI: 0.55-0.91; P = .007). In addition, a decreased GNRI predicted the occurrence of dropout from PD (HR = 0.971, 95% CI: 0.945-0.998, P = .034) and MACCE (HR = 0.95, 95% CI: 0.92-0.98, P = .001). However, no significant associations of the GNRI with technique failure (P = .167) or peritonitis (P = .96) were observed.

CONCLUSION

A low GNRI is significantly associated with poor clinical outcomes and might serve as a novel and valuable prognostic indicator among PD patients.

Insulin resistance in chronic kidney disease: a systematic review

Insulin resistance (IR) is an early metabolic alteration in chronic kidney disease (CKD) patients, being apparent when the glomerular filtration rate is still within the normal range and becoming almost universal in those who reach the end stage of kidney failure. The skeletal muscle represents the primary site of IR in CKD, and alterations at sites beyond the insulin receptor are recognized as the main defect underlying IR in this condition. Estimates of IR based on fasting insulin concentration are easier and faster but may not be adequate in patients with CKD because renal insufficiency reduces insulin catabolism. The hyperinsulinemic euglycemic clamp is the gold standard for the assessment of insulin sensitivity because this technique allows a direct measure of skeletal muscle sensitivity to insulin. The etiology of IR in CKD is multifactorial in nature and may be secondary to disturbances that are prominent in renal diseases, including physical inactivity, chronic inflammation, oxidative stress, vitamin D deficiency, metabolic acidosis, anemia, adipokine derangement, and altered gut microbiome. IR contributes to the progression of renal disease by worsening renal hemodynamics by various mechanisms, including activation of the sympathetic nervous system, sodium retention, and downregulation of the natriuretic peptide system. IR has been solidly associated with intermediate mechanisms leading to cardiovascular (CV) disease in CKD including left ventricular hypertrophy, vascular dysfunction, and atherosclerosis. However, it remains unclear whether IR is an independent predictor of mortality and CV complications in CKD. Because IR is a modifiable risk factor and its reduction may lower CV morbidity and mortality, unveiling the molecular mechanisms responsible for the pathogenesis of CKD-related insulin resistance is of importance for the identification of novel therapeutic targets aimed at reducing the high CV risk of this condition.