Relationship between relative interdialytic weight gain and serum leptin levels, nutrition, and inflammation in chronic hemodialysis patients

Introduction: Excessive rela- tive interdialytic weight gain (RIDWG, %) is an important risk factor for long-term ad- verse cardiovascular outcomes in chronic hemodialysis (HD) patients. On the other hand, it may also be an index of good appe- tite and nutritional status. We aimed to assess the relationship between RIDWG and appe- tite, nutrition, inflammation parameters, and to determine short-term survival of chronic HD patients. Methods: 100 chronic anuric HD patients were enrolled in this prospec- tive study between January 2013 and Janu- ary 2014. Patients with hospitalization, ma- jor surgery, obvious infectious/inflammatory disease, end-stage liver disease, malignan- cies, and malabsorption syndromes were ex- cluded. Patients were divided into 3 groups according to their RIDWG levels; group 1 = RIDWG 5%. Results: Group 3 patients were younger (p = 0.011) and had a lower body mass index (BMI) (p = 0.014). Nutrition and inflammation parameters in- cluding malnutrition inflammation score (MIS), serum albumin, prealbumin, triceps skinfold thickness, hs-CRP, and TNF-α were not significantly different between the groups. Leptin and leptin/BMI ratio were significantly lower in group 3 (p = 0.001). RIDWG was negatively correlated with age (p = 0.001, r = -0.371), BMI (p = 0.001, r = -0.372), leptin (p = 0.001, r = -0.369), leptin/BMI (p = 0.001, r = -0.369). After ad- justment for BMI in linear regression analy- sis, leptin/BMI remained significantly corre- lated with RIDWG (p = 0.024). Conclusion: This study revealed that RIDWG was associ- ated with younger age, lower BMI and dry weight, and lower serum leptin levels. More detailed studies are needed to validate and dissect the mechanisms of these findings.